{"type":"doc","content":[{"type":"paragraph","content":[{"text":" ","type":"text"}]},{"type":"extension","attrs":{"layout":"default","extensionType":"com.atlassian.confluence.macro.core","extensionKey":"toc","parameters":{"macroParams":{"minLevel":{"value":"1"},"maxLevel":{"value":"6"},"outline":{"value":"false"},"style":{"value":"none"},"type":{"value":"list"},"printable":{"value":"false"}},"macroMetadata":{"macroId":{"value":"73fe4952-b25d-45b3-9860-b7315cd1f217"},"schemaVersion":{"value":"1"},"title":"目录"}},"localId":"6b27f873-10fc-4707-b9d9-c60e6ba6f798"}},{"type":"paragraph","content":[{"text":"client通过发送ConfigureWindow请求配置窗口，配置窗口的内容包括窗口位置、窗口尺寸、窗口栈的调整、窗口边框大小等。X11 Server通过ProcConfigureWindow请求，调用ConfigureWindow实现。","type":"text"}]},{"type":"orderedList","attrs":{"order":1},"content":[{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"根据掩码获取窗口的新坐标，宽高尺寸（CWX | CWY | CWWidth | CWHeight）等。涉及窗口移动和缩放","type":"text"}]}]},{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"根据掩码获取窗口边框大小，窗口栈调整位置等","type":"text"}]},{"type":"orderedList","attrs":{"order":1},"content":[{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"CWBorderWidth：调整窗口边框","type":"text"}]}]},{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"CWStackMode：调整窗口在栈中的位置，包括：TopIf、BottomIf、Opposite、Above、Below等；其中CWSibling可指定相对哪个兄弟窗口的栈位置变化","type":"text"}]}]},{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"重定向ConfigureWindow请求至管理客户端，如：窗口管理器等，发送ConfigureRequest事件","type":"text"}]}]},{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"重定向窗口缩放至管理客户端，发送ResizeRequest事件","type":"text"}]}]},{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"通过回调ConfigNotify函数告知服务端的X11扩展协议窗口配置变化，如：composite等","type":"text"}]}]},{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"通过发送ConfigureNotify事件，通知感兴趣的client窗口配置变化","type":"text"}]}]},{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"回调ChangeBorderWidth处理边框","type":"text"}]}]},{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"回调MoveWindow处理窗口移动","type":"text"}]}]},{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"回调ResizeWindow处理窗口缩放","type":"text"}]}]},{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"调用ReflectStackChange处理窗口在窗口栈中的位置变化","type":"text"}]}]},{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"调用CheckCursorConfinement处理在窗口以及子窗口上的光标","type":"text"}]}]}]}]}]},{"type":"heading","attrs":{"level":1},"content":[{"text":"ReflectStackChange","type":"text"}]},{"type":"paragraph","content":[{"text":"对pWin窗口进行重排，新暴露的窗口的可见区域需要进行重绘。","type":"text"}]},{"type":"codeBlock","attrs":{"language":"c++"},"content":[{"text":"// 将pWin重排在pSib之上，若pSib为空，则将pWin重排在栈的底部\nstatic void ReflectStackChange(WindowPtr pWin, WindowPtr pSib, VTKind kind){\n Bool WasViewable = (Bool) pWin->viewable;\n Bool anyMarked;\n WindowPtr pFirstChange;\n WindowPtr pLayerWin;\n ScreenPtr pScreen = pWin->drawable.pScreen;\n if (!pWin->parent)\n return;\n // 更新pWin在窗口栈的位置，并计算第一个在栈中重新暴露的窗口：\n // pWin在pNextSib之上（窗口下移），则为pWin->nextSib\n // pWin在pNextSib之下（窗口上移），则为pWin\n pFirstChange = MoveWindowInStack(pWin, pSib);\n if (WasViewable) {\n // 调用miMarkOverlappedWindows，从pFirstChange开始向后遍历其兄弟窗口，标记被pWin重叠的窗口，若存在返回true\n anyMarked = (*pScreen->MarkOverlappedWindows) (pWin, pFirstChange, &pLayerWin);\n if (pLayerWin != pWin)\n pFirstChange = pLayerWin;\n if (anyMarked) {\n // 调用miValidateTree重新计算pWin父窗口及其子窗口的可见区域，并计算待重新绘制区域（需重新显示的区域）\n (*pScreen->ValidateTree) (pLayerWin->parent, pFirstChange, kind);\n // 调用miHandleValidateExposures，深度优先，先绘制边框，再绘制背景，然后发送Expose事件给客户端绘制\n (*pScreen->HandleExposures) (pLayerWin->parent);\n if (pWin->drawable.pScreen->PostValidateTree)\n (*pScreen->PostValidateTree) (pLayerWin->parent, pFirstChange, kind);\n }\n }\n if (pWin->realized)\n WindowsRestructured();\n}","type":"text"}]},{"type":"heading","attrs":{"level":2},"content":[{"text":"MarkOverlappedWindows","type":"text"}]},{"type":"paragraph","content":[{"text":"miMarkOverlappedWindows实现了MarkOverlappedWindows回调功能。该函数主要时过滤一批确定不需要重绘的窗口，识别有可能会需重新绘制的窗口，从而减少后续的计算量。在pWin窗口之上兄弟窗口不存在重绘的需求，可以过滤；在pWin窗口之下的窗口有可能会要求重新绘制，如：pWin窗口缩小了，pWin窗口的边框改变了，pWin窗口移动了等。","type":"text"}]},{"type":"codeBlock","attrs":{"language":"c++"},"content":[{"text":"// pWin为需重排的窗口，pFirst为第一个改变显示的窗口，pWin和pFirst为同一层窗口\n// pWin窗口向下移，pFirst为窗口原堆叠层的pWin的下一个相邻窗口（pWin->nextSib），标记与pWin重叠的窗口\n// pWin窗口向上移，pFirst为pWin本身窗口，标记被pWin遮挡的窗口\nBool miMarkOverlappedWindows(WindowPtr pWin, WindowPtr pFirst, WindowPtr *ppLayerWin){\n BoxPtr box;\n WindowPtr pChild, pLast;\n Bool anyMarked = FALSE;\n MarkWindowProcPtr MarkWindow = pWin->drawable.pScreen->MarkWindow;\n if (ppLayerWin)\n *ppLayerWin = pWin;\n\n if (pWin == pFirst) {\n // Blindly mark pWin and all of its inferiors. This is a slight overkill \n // if there are mapped windows that outside pWin's border, \n // but it's better than wasting time on RectIn checks.\n pChild = pWin;\n // 深度优先遍历，初始化该窗口及其子窗口的窗口和边框区域\n // 子窗口的区域限制在pWin的窗口（winSize）区域内\n while (1) {\n if (pChild->viewable) {\n // 根据窗口的drawable构建winSize区域，该区域限制在父窗口的winSize范围内\n if (RegionBroken(&pChild->winSize))\n SetWinSize(pChild);\n // 包括窗口边框的区域，该区域限制在父窗口的winSize范围内\n if (RegionBroken(&pChild->borderSize))\n SetBorderSize(pChild);\n // miMarkWindow, 构建Validate对象，记录起始坐标\n (*MarkWindow) (pChild);\n if (pChild->firstChild) {\n pChild = pChild->firstChild;\n continue;\n }\n }\n while (!pChild->nextSib && (pChild != pWin))\n pChild = pChild->parent;\n // pWin的子窗口遍历完成，退出循环\n if (pChild == pWin)\n break;\n pChild = pChild->nextSib;\n }\n // pWin窗口向上移，pWin为第一个暴露的窗口，可能需要重绘，因此需标记\n anyMarked = TRUE;\n // 下一个相邻窗口\n pFirst = pFirst->nextSib;\n }\n if ((pChild = pFirst)) {\n // pWin区间，窗口向上移，该区域会遮挡相邻窗口，向下移，则会暴露相邻窗口\n box = RegionExtents(&pWin->borderSize);\n pLast = pChild->parent->lastChild;\n while (1) {\n if (pChild->viewable) {\n if (RegionBroken(&pChild->winSize))\n SetWinSize(pChild);\n if (RegionBroken(&pChild->borderSize))\n SetBorderSize(pChild);\n // 区域有重叠，这标记该窗口，可能被遮挡，也可能会被暴露\n if (RegionContainsRect(&pChild->borderSize, box)) {\n // 调用miMarkWindow\n (*MarkWindow) (pChild);\n anyMarked = TRUE;\n if (pChild->firstChild) {\n pChild = pChild->firstChild;\n continue;\n }\n }\n }\n while (!pChild->nextSib && (pChild != pLast))\n pChild = pChild->parent;\n if (pChild == pLast)\n break;\n pChild = pChild->nextSib;\n }\n }\n if (anyMarked)\n (*MarkWindow) (pWin->parent);\n return anyMarked;\n}","type":"text"}]},{"type":"heading","attrs":{"level":2},"content":[{"text":"ValidateTree","type":"text"}]},{"type":"paragraph","content":[{"text":"计算窗口及其子窗口的clipList，boardList，exposed区域。","type":"text"}]},{"type":"orderedList","attrs":{"order":1},"content":[{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"计算可能变化的可见区域(totalClip)，为减少重绘开销。有两种方式：","type":"text"}]},{"type":"orderedList","attrs":{"order":1},"content":[{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"父窗口的borderClip区域减去pChild之上的子窗口区域（boarderSize），这些子窗口区域的显示内容不会改变","type":"text"}]}]},{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"所有与移动窗口有重叠的子窗口的可见区域之和，为父窗口的最大可见区域，这些区域的内容会发生变化","type":"text"}]}]}]}]},{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"过滤优化：在可见区域（totalClip）内，计算子窗口间是否重叠，若无，则不需重绘","type":"text"}]}]},{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"子窗口的clipList，boardList，exposed区域，按照深度优先递归计算窗口的可见区域","type":"text"}]},{"type":"orderedList","attrs":{"order":1},"content":[{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"窗口当可见性发生变化时（Unobscured, PartiallyObscured, FullyObscured），可能发送VisibilityNotify事件","type":"text"}]}]},{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"当可见区域发生变化时，回调ClipNotify函数（present_clip_notify/compClipNotify/xf86XVClipNotify）","type":"text"}]}]}]}]},{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"计算父窗口的可见区域，需重绘区域（exposed）等","type":"text"}]}]}]},{"type":"codeBlock","attrs":{"language":"c++"},"content":[{"text":"int miValidateTree(WindowPtr pParent, WindowPtr pChild, VTKind kind) {\n // Total clipping region available to the marked children. \n // pParent's clipList merged with the borderClips of all the marked children.\n RegionRec totalClip; \n RegionRec childClip; /* The new borderClip for the current child */\n RegionRec childUnion; /* the space covered by borderSize for all marked children */\n RegionRec exposed; /* For intermediate calculations */\n WindowPtr pWin;\n Bool overlap;\n int viewvals;\n Bool forward;\n\n ScreenPtr pScreen = pParent->drawable.pScreen;\n if (pChild == NullWindow)\n pChild = pParent->firstChild;\n RegionNull(&childClip);\n RegionNull(&exposed);\n\n // compute the area of the parent window occupied by the marked children + the parent itself. \n // This is the area which can be divied up among the marked children in their new configuration.\n RegionNull(&totalClip);\n viewvals = 0;\n // 计算可能变化的可见区域(totalClip)，有两种方法：\n // 1. 父窗口的borderClip区域减去pChild之上的子窗口区域（boarderSize），这些子窗口区域的显示内容不会改变\n // 2. 所有与移动窗口有重叠的子窗口的可见区域之和，为父窗口的最大可见区域，这些区域的内容会发生变化\n if (RegionBroken(&pParent->clipList) && !RegionBroken(&pParent->borderClip)) {\n // RegionBroken表示数据空间为空，一般来说根窗口的clipList置为broken，因为根窗口时常变化。\n kind = VTBroken;\n // When rebuilding clip lists after out of memory, assume everything is busted.\n forward = TRUE;\n RegionCopy(&totalClip, &pParent->borderClip);\n RegionIntersect(&totalClip, &totalClip, &pParent->winSize);\n // 在pChild之上的相邻窗口，遮挡了pParent，减去pWin的窗口大小（加上边框）\n // 如果pWin为compositor client管理，可能需要透明化，因此不能将其区域去掉\n for (pWin = pParent->firstChild; pWin != pChild; pWin = pWin->nextSib) {\n if (pWin->viewable && !TreatAsTransparent(pWin))\n RegionSubtract(&totalClip, &totalClip, &pWin->borderSize);\n }\n for (pWin = pChild; pWin; pWin = pWin->nextSib)\n if (pWin->valdata && pWin->viewable)\n viewvals++;\n RegionEmpty(&pParent->clipList);\n }\n else {\n // pChild后续相邻窗口的可见区域之和，即为pWin最大可见区域\n if ((pChild->drawable.y < pParent->lastChild->drawable.y) ||\n ((pChild->drawable.y == pParent->lastChild->drawable.y) &&\n (pChild->drawable.x < pParent->lastChild->drawable.x))) {\n forward = TRUE;\n for (pWin = pChild; pWin; pWin = pWin->nextSib) {\n if (pWin->valdata) { // 与移动窗口有重叠\n RegionAppend(&totalClip, getBorderClip(pWin));\n if (pWin->viewable)\n viewvals++;\n }\n }\n }\n else {\n forward = FALSE;\n pWin = pParent->lastChild;\n while (1) {\n if (pWin->valdata) { // 与移动窗口有重叠\n RegionAppend(&totalClip, getBorderClip(pWin));\n if (pWin->viewable)\n viewvals++;\n }\n if (pWin == pChild)\n break;\n pWin = pWin->prevSib;\n }\n }\n RegionValidate(&totalClip, &overlap);\n }\n // Now go through the children of the root and figure their new borderClips from the totalClip, \n // passing that off to miComputeClips to handle recursively. \n // Once that's done, we remove the child from the totalClip to clip any siblings below it.\n overlap = TRUE;\n // 在可见区域（totalClip）内，计算子窗口间是否重叠，若无，则不需重绘\n if (kind != VTStack) {\n // 子窗口的可见区域加上父窗口的可见区域，为父窗口整个可见区域\n RegionUnion(&totalClip, &totalClip, &pParent->clipList);\n if (viewvals > 1) {\n // precompute childUnion to discover whether any of them overlap. \n // This seems redundant, but performance studies have demonstrated \n // that the cost of this loop is lower than the cost of multiple Subtracts in the loop below.\n RegionNull(&childUnion);\n if (forward) {\n for (pWin = pChild; pWin; pWin = pWin->nextSib)\n if (pWin->valdata && pWin->viewable && !TreatAsTransparent(pWin))\n RegionAppend(&childUnion, &pWin->borderSize);\n }\n else {\n pWin = pParent->lastChild;\n while (1) {\n if (pWin->valdata && pWin->viewable && !TreatAsTransparent(pWin))\n RegionAppend(&childUnion, &pWin->borderSize);\n if (pWin == pChild)\n break;\n pWin = pWin->prevSib;\n }\n }\n // 窗口之间是否有重叠，若无重叠，不需要重绘。\n RegionValidate(&childUnion, &overlap);\n if (overlap)\n RegionUninit(&childUnion);\n }\n }\n for (pWin = pChild; pWin != NullWindow; pWin = pWin->nextSib) {\n if (pWin->viewable) {\n if (pWin->valdata) {\n RegionIntersect(&childClip, &totalClip, &pWin->borderSize);\n // 计算pWin及其子窗口的clipList，boardList，exposed区域\n miComputeClips(pWin, pScreen, &childClip, kind, &exposed);\n if (overlap && !TreatAsTransparent(pWin)) {\n // pWin遮挡了下层的窗口，下层窗口对boarderSize区域不可见，因此可以去掉该区域\n RegionSubtract(&totalClip, &totalClip, &pWin->borderSize);\n }\n }\n else if (pWin->visibility == VisibilityNotViewable) {\n miTreeObscured(pWin);\n }\n }\n else { // 不可显示，则清空clipList，删除临时数据\n if (pWin->valdata) {\n RegionEmpty(&pWin->clipList);\n if (pScreen->ClipNotify)\n (*pScreen->ClipNotify) (pWin, 0, 0);\n RegionEmpty(&pWin->borderClip);\n pWin->valdata = NULL;\n }\n }\n }\n RegionUninit(&childClip);\n // 计算父窗口的可剪接区域，需重绘区域等\n if (!overlap) {\n // 没重叠，减去子窗口的可见区域，即为父窗口的可见区域\n RegionSubtract(&totalClip, &totalClip, &childUnion);\n RegionUninit(&childUnion);\n }\n RegionNull(&pParent->valdata->after.exposed);\n RegionNull(&pParent->valdata->after.borderExposed);\n\n // each case below is responsible for updating the clipList and serial number for the parent window\n switch (kind) {\n case VTStack:\n // 子窗口间的堆叠层次变化，不影响父窗口的clipList区域\n break;\n default:\n // totalClip contains the new clipList for the parent. \n // Figure out exposures and obscures as per miComputeClips and reset the parent's clipList.\n // 只重绘未绘制区域。clipList中的区域已绘制。边框不需要重绘，因为子窗口从未覆盖边框\n RegionSubtract(&pParent->valdata->after.exposed, &totalClip, &pParent->clipList);\n /* fall through */\n case VTMap:\n // 更新clipList为新的可见区域\n RegionCopy(&pParent->clipList, &totalClip);\n pParent->drawable.serialNumber = NEXT_SERIAL_NUMBER;\n break;\n }\n\n RegionUninit(&totalClip);\n RegionUninit(&exposed);\n if (pScreen->ClipNotify)\n (*pScreen->ClipNotify) (pParent, 0, 0);\n return 1;\n}","type":"text"}]},{"type":"heading","attrs":{"level":2},"content":[{"text":"HandleValidateExposures","type":"text"}]},{"type":"paragraph","content":[{"text":"发送重绘（Expose）事件，采用深度优先遍历窗口树","type":"text"}]},{"type":"orderedList","attrs":{"order":1},"content":[{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"重绘父窗口图形","type":"text"}]},{"type":"orderedList","attrs":{"order":1},"content":[{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"Server调用PaintWindow绘制边框","type":"text"}]}]},{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"调用WindowExposures","type":"text"}]},{"type":"orderedList","attrs":{"order":1},"content":[{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"Server调用PaintWindow绘制窗口背景","type":"text"}]}]},{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"发送重绘事件给客户端","type":"text"}]}]}]}]}]}]},{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"重绘子窗口图形，流程与上类似","type":"text"}]}]}]},{"type":"codeBlock","attrs":{"language":"c++"},"content":[{"text":"void miHandleValidateExposures(WindowPtr pWin){\n WindowPtr pChild;\n ValidatePtr val;\n WindowExposuresProcPtr WindowExposures;\n pChild = pWin;\n WindowExposures = pChild->drawable.pScreen->WindowExposures;\n // 深度优先，先绘制边框，再绘制背景，然后发送Expose事件给客户端绘制\n while (1) {\n if ((val = pChild->valdata)) {\n if (RegionNotEmpty(&val->after.borderExposed))\n // 调用miPaintWindow\n pWin->drawable.pScreen->PaintWindow(pChild, &val->after.borderExposed, PW_BORDER);\n RegionUninit(&val->after.borderExposed);\n // xf86XVWindowExposures -> miWindowExposures\n (*WindowExposures) (pChild, &val->after.exposed);\n RegionUninit(&val->after.exposed);\n free(val);\n pChild->valdata = NULL;\n if (pChild->firstChild) {\n pChild = pChild->firstChild;\n continue;\n }\n }\n while (!pChild->nextSib && (pChild != pWin))\n pChild = pChild->parent;\n if (pChild == pWin)\n break;\n pChild = pChild->nextSib;\n }\n}\n\nvoid miWindowExposures(WindowPtr pWin, RegionPtr prgn){\n RegionPtr exposures = prgn;\n if (prgn && !RegionNil(prgn)) {\n RegionRec expRec;\n int clientInterested =\n (pWin->eventMask | wOtherEventMasks(pWin)) & ExposureMask;\n if (clientInterested && (RegionNumRects(prgn) > RECTLIMIT)) {\n // If we have LOTS of rectangles, we decide to take the extents and force an exposure on that.\n // This should require much less work overall, on both client and server.\n // This is cheating, but isn't prohibited by the protocol (\"spontaneous combustion\" :-).\n BoxRec box = *RegionExtents(prgn);\n exposures = &expRec;\n RegionInit(exposures, &box, 1);\n RegionReset(prgn, &box);\n /* miPaintWindow doesn't clip, so we have to */\n RegionIntersect(prgn, prgn, &pWin->clipList);\n }\n // 重绘窗口背景\n pWin->drawable.pScreen->PaintWindow(pWin, prgn, PW_BACKGROUND);\n if (clientInterested) // 发送Expose事件\n miSendExposures(pWin, exposures, pWin->drawable.x, pWin->drawable.y);\n if (exposures == &expRec)\n RegionUninit(exposures);\n RegionEmpty(prgn);\n }\n}","type":"text"}]},{"type":"paragraph"},{"type":"heading","attrs":{"level":2},"content":[{"text":"WindowsRestructured","type":"text"}]},{"type":"paragraph","content":[{"text":"处理光标和键盘焦点，并重构光标窗口：","type":"text"}]},{"type":"orderedList","attrs":{"order":1},"content":[{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"计算获得当前焦点坐标所在窗口（最低级窗口）","type":"text"}]}]},{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"若当前焦点窗口与原窗口不同，则将焦点离开原窗口，进入新窗口","type":"text"}]}]},{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"如果是光标设备，则重绘光标窗口，根据光标所在窗口特性，可绘制不同的光标图形，一般由miPointerDisplayCursor函数实现，动画光标由AnimCurDisplayCursor实现","type":"text"}]}]}]},{"type":"codeBlock","attrs":{"language":"c++"},"content":[{"text":"void WindowsRestructured(void){\n DeviceIntPtr pDev = inputInfo.devices;\n while (pDev) {\n if (IsMaster(pDev) || IsFloating(pDev)) // 主输入设备或者与主输入设备关联的设备\n CheckMotion(NULL, pDev);\n pDev = pDev->next;\n }\n}\n\nBool CheckMotion(DeviceEvent *ev, DeviceIntPtr pDev){\n WindowPtr prevSpriteWin, newSpriteWin;\n SpritePtr pSprite = pDev->spriteInfo->sprite;\n prevSpriteWin = pSprite->win;\n // ev == NULL\n if (ev && !syncEvents.playingEvents) {\n // skipped\n }\n // 根据精灵的坐标获取包含在坐标的窗口\n newSpriteWin = XYToWindow(pSprite, pSprite->hot.x, pSprite->hot.y);\n if (newSpriteWin != prevSpriteWin) { // 光标所在的窗口发生了变化\n int sourceid;\n if (!ev) {\n UpdateCurrentTimeIf();\n sourceid = pDev->id; /* when from WindowsRestructured */\n }\n else\n sourceid = ev->sourceid;\n\n if (prevSpriteWin != NullWindow) {\n // 焦点离开prevSpriteWin窗口，进入newSpriteWin窗口，发送事件给client\n if (!ActivateEnterGrab(pDev, prevSpriteWin, newSpriteWin))\n DoEnterLeaveEvents(pDev, sourceid, prevSpriteWin, newSpriteWin, NotifyNormal);\n }\n pSprite->win = newSpriteWin;\n // 重绘新光标\n PostNewCursor(pDev);\n return FALSE;\n }\n return TRUE;\n}","type":"text"}]},{"type":"heading","attrs":{"level":1},"content":[{"text":"ConfigNotify","type":"text"}]},{"type":"paragraph","content":[{"text":"ConfigNotify回调通知X11扩展窗口配置发送变化，涉及一个回调函数链，其调用顺序为：","type":"text"}]},{"type":"orderedList","attrs":{"order":1},"content":[{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"present_config_notify：发送PresentConfigureNotify扩展事件给客户端","type":"text"}]}]},{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"compConfigNotify：针对拥有compWindow的窗口进行处理，若窗口尺寸有变化（ResizeWindow），则分配新的pixmap","type":"text"}]}]},{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"DRI2ConfigNotify：失效原有的显存内存","type":"text"}]}]}]},{"type":"codeBlock","attrs":{"language":"c++"},"content":[{"text":"// 回调函数原型\n// (x, y)相对与父窗口的窗口新坐标，包含边框\n// (w,h)窗口的新尺寸（宽高），宽高不包括边框\n// bw窗口的边框新大小\n// next_sib：窗口的相邻兄弟窗口，及窗口在next_sib窗口之上，这是窗口在窗口栈的新位置；为空表示窗口置底\nint ConfigNotify(WindowPtr pWin, int x, int y, int w, int h, int bw, WindowPtr pSib)","type":"text"}]},{"type":"heading","attrs":{"level":2},"content":[{"text":"present_config_notify","type":"text"}]},{"type":"paragraph","content":[{"text":"发送PresentConfigureNotify扩展事件给客户端。","type":"text"}]},{"type":"codeBlock","attrs":{"language":"c++"},"content":[{"text":"static int present_config_notify(WindowPtr window, int x, int y, int w, int h, int bw, WindowPtr sibling) {\n int ret;\n ScreenPtr screen = window->drawable.pScreen;\n present_screen_priv_ptr screen_priv = present_screen_priv(screen);\n // 发送PresentConfigureNotify扩展事件给客户端\n present_send_config_notify(window, x, y, w, h, bw, sibling, 0);\n unwrap(screen_priv, screen, ConfigNotify);\n // 调用compConfigNotify\n if (screen->ConfigNotify)\n ret = screen->ConfigNotify (window, x, y, w, h, bw, sibling);\n else\n ret = 0;\n wrap(screen_priv, screen, ConfigNotify, present_config_notify);\n return ret;\n}\n","type":"text"}]},{"type":"heading","attrs":{"level":2},"content":[{"text":"compConfigNotify","type":"text"}]},{"type":"paragraph","content":[{"text":"针对拥有compWindow的窗口进行处理，若窗口尺寸有变化，则分配新的pixmap，并将父窗口pixmap中新区域的窗口内容拷贝至新的pixmap中，若窗口的色彩深度与父窗口不同，则内容需要进行合成，旧的pixmap缓冲在cw->pOldPixmap中","type":"text"}]},{"type":"codeBlock","attrs":{"language":"c++"},"content":[{"text":"\nint compConfigNotify(WindowPtr pWin, int x, int y, int w, int h, int bw, WindowPtr pSib){\n ScreenPtr pScreen = pWin->drawable.pScreen;\n CompScreenPtr cs = GetCompScreen(pScreen);\n Bool ret = 0;\n WindowPtr pParent = pWin->parent;\n int draw_x, draw_y;\n Bool alloc_ret;\n // 调用DRI2ConfigNotify\n if (cs->ConfigNotify) {\n pScreen->ConfigNotify = cs->ConfigNotify;\n ret = (*pScreen->ConfigNotify) (pWin, x, y, w, h, bw, pSib);\n cs->ConfigNotify = pScreen->ConfigNotify;\n pScreen->ConfigNotify = compConfigNotify;\n if (ret)\n return ret;\n }\n if (pWin->redirectDraw == RedirectDrawNone)\n return Success;\n // 计算窗口可绘制区域屏幕坐标，当尺寸不同时，重新分配pixmap\n draw_x = pParent->drawable.x + x + bw;\n draw_y = pParent->drawable.y + y + bw;\n alloc_ret = compReallocPixmap(pWin, draw_x, draw_y, w, h, bw);\n if (alloc_ret == FALSE)\n return BadAlloc;\n return Success;\n}\n\nBool compReallocPixmap(WindowPtr pWin, int draw_x, int draw_y, unsigned int w, unsigned int h, int bw){\n ScreenPtr pScreen = pWin->drawable.pScreen;\n PixmapPtr pOld = (*pScreen->GetWindowPixmap) (pWin);\n PixmapPtr pNew;\n CompWindowPtr cw = GetCompWindow(pWin);\n int pix_x, pix_y;\n int pix_w, pix_h;\n cw->oldx = pOld->screen_x;\n cw->oldy = pOld->screen_y;\n pix_x = draw_x - bw;\n pix_y = draw_y - bw;\n pix_w = w + (bw << 1);\n pix_h = h + (bw << 1);\n if (pix_w != pOld->drawable.width || pix_h != pOld->drawable.height) {\n // 创建一个新的pixmap，包括边框尺寸，从父窗口的画布的新区域中拷贝内容至新的pixmap中\n pNew = compNewPixmap(pWin, pix_x, pix_y, pix_w, pix_h);\n if (!pNew)\n return FALSE;\n // 缓冲旧的pixmap，设置新的pixmap给窗口\n cw->pOldPixmap = pOld;\n compSetPixmap(pWin, pNew, bw);\n }\n else {\n pNew = pOld; // 尺寸不变（包括了边框），这更新坐标信息，旧坐标信息缓冲在cw->oldX/Y中\n cw->pOldPixmap = 0;\n }\n pNew->screen_x = pix_x; // 包含的边框的屏幕坐标\n pNew->screen_y = pix_y;\n return TRUE;\n}\n","type":"text"}]},{"type":"heading","attrs":{"level":1},"content":[{"text":"MoveWindow","type":"text"}]},{"type":"paragraph","content":[{"text":"移动窗口涉及窗口原位置遮挡的兄弟窗口需要显示内容，窗口移动后须在新位置显示窗口内容。其实现涉及一个回调函数链，包括：xwayland、composite、machine independent的回调函数。其调用顺序为：","type":"text"}]},{"type":"orderedList","attrs":{"order":1},"content":[{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"xwl_move_window：更新顶层窗口的视口（viewport）","type":"text"}]}]},{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"compMoveWindow：处理compWindow","type":"text"}]}]},{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"miMoveWindow：移动窗口，重新计算子窗口的位置和尺寸，显示窗口内容等","type":"text"}]}]}]},{"type":"codeBlock","attrs":{"language":"c++"},"content":[{"text":"// 回调函数原型\n// (x, y)相对与父窗口的窗口新坐标\n// next_sib：窗口的相邻兄弟窗口，及窗口在next_sib窗口之上，这是窗口在窗口栈的新位置；为空表示窗口置底\n// kind：验证窗口树的类型，VTMove：只移动，VTOther：涉及边框的变化\nvoid MoveWindow(WindowPtr window, int x, int y, WindowPtr next_sib, VTKind kind);","type":"text"}]},{"type":"heading","attrs":{"level":2},"content":[{"text":"xwl_move_window","type":"text"}]},{"type":"paragraph","content":[{"text":"在非根模式下，额外处理顶级窗口与视口之间的关系，窗口内容在Wayland compositor视口中显示，可能只显示一部分内容。","type":"text"}]},{"type":"codeBlock","attrs":{"language":"c++"},"content":[{"text":"\nvoid xwl_move_window(WindowPtr window, int x, int y, WindowPtr next_sib, VTKind kind){\n ScreenPtr screen = window->drawable.pScreen;\n struct xwl_screen *xwl_screen = xwl_screen_get(screen);\n // 获取xwl_window窗口，window本身或者其祖先窗口对应的xwl_window窗口，存在xwl_window，则比存在一个wl_surface与window对应\n struct xwl_window *xwl_window = xwl_window_from_window(window);\n // 调用compMoveWindow\n screen->MoveWindow = xwl_screen->MoveWindow;\n (*screen->MoveWindow) (window, x, y, next_sib, kind);\n xwl_screen->MoveWindow = screen->MoveWindow;\n screen->MoveWindow = xwl_move_window;\n // window本身有对应的xwl_window窗口，如：窗口管理器创建的装饰窗口\n // 或window是顶层窗口（包括override-redirect和被窗口管理器装饰的顶层窗口）\n if (xwl_window && (xwl_window_get(window) || xwl_window_is_toplevel(window)))\n xwl_window_check_resolution_change_emulation(xwl_window);\n}\n\n// 处理窗口与视口（viewport）的关系\nvoid xwl_window_check_resolution_change_emulation(struct xwl_window *xwl_window)\n{\n struct xwl_emulated_mode emulated_mode;\n struct xwl_output *xwl_output;\n // Wayland compositor支持wp_viewporter_interface接口，获取一个xwl_output和对应的xwl_emulated_mode\n if (xwl_window_should_enable_viewport(xwl_window, &xwl_output, &emulated_mode))\n xwl_window_enable_viewport(xwl_window, xwl_output, &emulated_mode);\n else if (xwl_window_has_viewport_enabled(xwl_window))\n xwl_window_disable_viewport(xwl_window);\n}\n\n// 视口（viewport）与surface建立关系，并设置视口区域大小\nstatic void xwl_window_enable_viewport(struct xwl_window *xwl_window,\n struct xwl_output *xwl_output, struct xwl_emulated_mode *emulated_mode){\n if (!xwl_window_has_viewport_enabled(xwl_window)) {\n // 绑定视口与曲面（wl_surface）\n xwl_window->viewport = wp_viewporter_get_viewport(xwl_window->xwl_screen->viewporter, xwl_window->surface);\n }\n // 设置窗口的坐标和尺寸\n wp_viewport_set_source(xwl_window->viewport, wl_fixed_from_int(0), wl_fixed_from_int(0),\n wl_fixed_from_int(emulated_mode->width), wl_fixed_from_int(emulated_mode->height));\n // 设置视口（viewport）的尺寸，可显示区域\n wp_viewport_set_destination(xwl_window->viewport, xwl_output->width, xwl_output->height);\n // 计算缩放比例\n xwl_window->scale_x = (float)emulated_mode->width / xwl_output->width;\n xwl_window->scale_y = (float)emulated_mode->height / xwl_output->height;\n}","type":"text"}]},{"type":"heading","attrs":{"level":2},"content":[{"text":"compMoveWindow","type":"text"}]},{"type":"paragraph","content":[{"text":"回收compWindow中旧的pixmap资源","type":"text"}]},{"type":"codeBlock","attrs":{"language":"c++"},"content":[{"text":"void compMoveWindow(WindowPtr pWin, int x, int y, WindowPtr pSib, VTKind kind) {\n ScreenPtr pScreen = pWin->drawable.pScreen;\n CompScreenPtr cs = GetCompScreen(pScreen);\n // 调用miMoveWindow\n pScreen->MoveWindow = cs->MoveWindow;\n (*pScreen->MoveWindow) (pWin, x, y, pSib, kind);\n cs->MoveWindow = pScreen->MoveWindow;\n pScreen->MoveWindow = compMoveWindow;\n // 是否旧的pixmap，新pixmap可能在compCOnfigNofity中创建\n compFreeOldPixmap(pWin);\n compCheckTree(pScreen);\n}\n\nstatic void compFreeOldPixmap(WindowPtr pWin) {\n ScreenPtr pScreen = pWin->drawable.pScreen;\n if (pWin->redirectDraw != RedirectDrawNone) {\n // 该窗口存在redirectWindow，且缓冲了旧的pixmap，则释放旧的pixmap\n CompWindowPtr cw = GetCompWindow(pWin);\n if (cw->pOldPixmap) {\n (*pScreen->DestroyPixmap) (cw->pOldPixmap);\n cw->pOldPixmap = NullPixmap;\n }\n }\n}","type":"text"}]},{"type":"heading","attrs":{"level":2},"content":[{"text":"miMoveWindow","type":"text"}]},{"type":"paragraph","content":[{"text":"实现窗口移动功能，窗口移动涉及原被遮挡窗口内容显示，窗口新位置内容显示，窗口栈的更新等，同时其子窗口也随之移动。","type":"text"}]},{"type":"orderedList","attrs":{"order":1},"content":[{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"标记在父窗口树中被pWin覆盖的窗口和子窗口，包括pWin本身以及子窗口","type":"text"}]}]},{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"更新pWin窗口尺寸和坐标，坐标平移，截取超过父窗口边界的区域","type":"text"}]}]},{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"更新pWin子窗口的尺寸和坐标，坐标平移，截取超过pWin窗口边界的区域","type":"text"}]}]},{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"根据pWin的新窗口，计算屏幕可能变化的区域，并计算窗口及子窗口的可见区域，重绘区域等。","type":"text"}]}]},{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"将pWin窗口的原有效内容迁移至新窗口内","type":"text"}]}]},{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"根据窗口exposed向client发送重绘请求","type":"text"}]}]}]},{"type":"codeBlock","attrs":{"language":"c++"},"content":[{"text":"void miMoveWindow(WindowPtr pWin, int x, int y, WindowPtr pNextSib, VTKind kind){\n WindowPtr pParent;\n Bool WasViewable = (Bool) (pWin->viewable);\n short bw;\n RegionPtr oldRegion = NULL;\n DDXPointRec oldpt;\n Bool anyMarked = FALSE;\n ScreenPtr pScreen;\n WindowPtr windowToValidate;\n WindowPtr pLayerWin;\n if (!(pParent = pWin->parent))\n return;\n pScreen = pWin->drawable.pScreen;\n bw = wBorderWidth(pWin);\n oldpt.x = pWin->drawable.x;\n oldpt.y = pWin->drawable.y;\n if (WasViewable) {\n oldRegion = RegionCreate(NullBox, 1);\n // 缓冲原剪接区间\n RegionCopy(oldRegion, &pWin->borderClip);\n // 调用miMarkOverlappedWindows，从pWin开始向后遍历其兄弟窗口，标记被pWin覆盖的窗口（窗口移动前），若存在返回true\n anyMarked = (*pScreen->MarkOverlappedWindows) (pWin, pWin, &pLayerWin);\n }\n // origin (x,y)为窗口可绘制区域的新坐标，相对于父窗口\n pWin->origin.x = x + (int) bw;\n pWin->origin.y = y + (int) bw;\n // (x,y)窗口可绘制区域的屏幕新坐标\n x = pWin->drawable.x = pParent->drawable.x + x + (int) bw;\n y = pWin->drawable.y = pParent->drawable.y + y + (int) bw;\n // 设置窗口区域，若有compWindow，则为窗口实际大小，否则为父窗口范围内窗口区域\n SetWinSize(pWin);\n // 设置包含边框的窗口区域，原理同上\n SetBorderSize(pWin);\n // 回调PositionWindow通知X11扩展窗口位置更新\n // miDbePositionWindow -> compPositionWindow -> fbPositionWindow\n (*pScreen->PositionWindow) (pWin, x, y);\n // 更新pWin在窗口栈的位置，并计算第一个在栈中重新暴露的窗口：\n // pWin在pNextSib之上（窗口下移），则为pWin->nextSib\n // pWin在pNextSib之下（窗口上移），则为pWin\n windowToValidate = MoveWindowInStack(pWin, pNextSib);\n // 重新计算子窗口在新位置的窗口尺寸，由于窗口的移动，可能导致某些内容移出父窗口，则必须截取窗口尺寸\n ResizeChildrenWinSize(pWin, x - oldpt.x, y - oldpt.y, 0, 0);\n if (WasViewable) {\n if (pLayerWin == pWin) // 该条件恒成立，不知为什么需要判断\n // 从windowToValidate开始向后遍历其兄弟窗口，标记与pWin重叠的窗口（窗口移动后（坐标已更新））\n anyMarked |= (*pScreen->MarkOverlappedWindows)(pWin, windowToValidate, NULL);\n else\n anyMarked |= (*pScreen->MarkOverlappedWindows)(pWin, pLayerWin, NULL);\n if (anyMarked) { // 有重叠，有些窗口被遮挡，有些窗口重新显示\n // 调用miValidateTree重新计算pWin父窗口及其子窗口的可见区域，并计算待重新绘制区域（需重新显示的区域）\n (*pScreen->ValidateTree) (pLayerWin->parent, NullWindow, kind);\n // compCopyWindow -> damageCopyWindow -> glamor_copy_window\n // 将window中的内容拷贝至新位置\n (*pWin->drawable.pScreen->CopyWindow) (pWin, oldpt, oldRegion);\n RegionDestroy(oldRegion);\n // 调用miHandleValidateExposures，深度优先，先绘制边框，再绘制背景，然后发送Expose事件给客户端绘制\n (*pScreen->HandleExposures) (pLayerWin->parent);\n if (pScreen->PostValidateTree)\n (*pScreen->PostValidateTree) (pLayerWin->parent, NULL, kind);\n }\n }\n if (pWin->realized) // 重构所有窗口\n WindowsRestructured();\n}","type":"text"}]},{"type":"heading","attrs":{"level":3},"content":[{"text":"compCopyWindow","type":"text"}]},{"type":"paragraph","content":[{"text":"分两种情况更新新区域内容","type":"text"}]},{"type":"orderedList","attrs":{"order":1},"content":[{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"窗口有compWindow，若窗口尺寸未变，则创建Damage，告知新区域内容有变化；若窗口尺寸变化时，pixmap为新区域的内容，需将旧pixmap的内容拷贝至pixmap中，更新窗口内容至新区域。","type":"text"}]}]},{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"窗口无compWindow，则传递给后续的CopyWindow处理","type":"text"}]}]}]},{"type":"codeBlock","attrs":{"language":"c++"},"content":[{"text":"\nvoid compCopyWindow(WindowPtr pWin, DDXPointRec ptOldOrg, RegionPtr prgnSrc)\n{\n ScreenPtr pScreen = pWin->drawable.pScreen;\n CompScreenPtr cs = GetCompScreen(pScreen);\n int dx = 0, dy = 0;\n if (pWin->redirectDraw != RedirectDrawNone) {\n PixmapPtr pPixmap = (*pScreen->GetWindowPixmap) (pWin);\n CompWindowPtr cw = GetCompWindow(pWin);\n if (cw->pOldPixmap) {\n // 窗口尺寸有改变，在compConfigNofity中创建了新的pixmap，旧的pixmap缓冲在pOldPixmap中\n // 将pOldPixmap的内容拷贝至新的pixmap中即可，覆盖新pixmap中响应区域内容\n RegionRec rgnDst;\n GCPtr pGC;\n // 计算窗口移动时产生的坐标偏移\n dx = ptOldOrg.x - pWin->drawable.x;\n dy = ptOldOrg.y - pWin->drawable.y;\n RegionTranslate(prgnSrc, -dx, -dy);\n RegionNull(&rgnDst);\n // 区域限制在borderClip范围内\n RegionIntersect(&rgnDst, &pWin->borderClip, prgnSrc);\n // 坐标转换，从屏幕坐标转换为本地坐标（画布内的坐标）\n RegionTranslate(&rgnDst, -pPixmap->screen_x, -pPixmap->screen_y);\n // 坐标偏移转换为old和new pixmap内的偏移\n dx = dx + pPixmap->screen_x - cw->oldx;\n dy = dy + pPixmap->screen_y - cw->oldy;\n pGC = GetScratchGC(pPixmap->drawable.depth, pScreen);\n if (pGC) {\n BoxPtr pBox = RegionRects(&rgnDst);\n int nBox = RegionNumRects(&rgnDst);\n ValidateGC(&pPixmap->drawable, pGC);\n while (nBox--) {\n // 调用glamor_copy_area拷贝数据\n (void) (*pGC->ops->CopyArea) (&cw->pOldPixmap->drawable, &pPixmap->drawable, pGC,\n pBox->x1 + dx, pBox->y1 + dy, pBox->x2 - pBox->x1,\n pBox->y2 - pBox->y1, pBox->x1, pBox->y1);\n pBox++;\n }\n FreeScratchGC(pGC);\n }\n RegionUninit(&rgnDst);\n return;\n }\n // 矫正旧坐标，加上新pixmap的屏幕坐标与旧pixmap的偏移，方便后续操作区分\n dx = pPixmap->screen_x - cw->oldx;\n dy = pPixmap->screen_y - cw->oldy;\n ptOldOrg.x += dx;\n ptOldOrg.y += dy;\n }\n\n pScreen->CopyWindow = cs->CopyWindow;\n if (ptOldOrg.x != pWin->drawable.x || ptOldOrg.y != pWin->drawable.y) {\n // 窗口无compWindow，需要将内容从旧坐标移至新坐标\n if (dx || dy)\n RegionTranslate(prgnSrc, dx, dy);\n // damageCopyWindow\n (*pScreen->CopyWindow) (pWin, ptOldOrg, prgnSrc);\n if (dx || dy)\n RegionTranslate(prgnSrc, -dx, -dy);\n }\n else {\n // 还原旧坐标，见上的矫正\n ptOldOrg.x -= dx;\n ptOldOrg.y -= dy;\n // 更新prgnSrc至新坐标区域，构建Damage，通知新区域内容有变化\n RegionTranslate(prgnSrc, pWin->drawable.x - ptOldOrg.x, pWin->drawable.y - ptOldOrg.y);\n DamageDamageRegion(&pWin->drawable, prgnSrc);\n }\n cs->CopyWindow = pScreen->CopyWindow;\n pScreen->CopyWindow = compCopyWindow;\n compCheckTree(pWin->drawable.pScreen);\n}","type":"text"}]},{"type":"heading","attrs":{"level":3},"content":[{"text":"damageCopyWindow","type":"text"}]},{"type":"paragraph","content":[{"text":"创建Damage，记录变化区域","type":"text"}]},{"type":"codeBlock","attrs":{"language":"c++"},"content":[{"text":"\nstatic void damageCopyWindow(WindowPtr pWindow, DDXPointRec ptOldOrg, RegionPtr prgnSrc){\n ScreenPtr pScreen = pWindow->drawable.pScreen;\n damageScrPriv(pScreen);\n if (getWindowDamage(pWindow)) {\n int dx = pWindow->drawable.x - ptOldOrg.x;\n int dy = pWindow->drawable.y - ptOldOrg.y;\n // The region comes in source relative, but the damage occurs at the destination location.\n // Translate back and forth.\n RegionTranslate(prgnSrc, dx, dy);\n damageRegionAppend(&pWindow->drawable, prgnSrc, FALSE, -1);\n RegionTranslate(prgnSrc, -dx, -dy);\n }\n unwrap(pScrPriv, pScreen, CopyWindow);\n // glamor_copy_window\n (*pScreen->CopyWindow) (pWindow, ptOldOrg, prgnSrc);\n damageRegionProcessPending(&pWindow->drawable);\n wrap(pScrPriv, pScreen, CopyWindow, damageCopyWindow);\n}","type":"text"}]},{"type":"heading","attrs":{"level":3},"content":[{"text":"glamor_copy_window","type":"text"}]},{"type":"paragraph","content":[{"text":"使用openGL拷贝数据","type":"text"}]},{"type":"codeBlock","attrs":{"language":"c++"},"content":[{"text":"\nvoid glamor_copy_window(WindowPtr window, DDXPointRec old_origin, RegionPtr src_region){\n PixmapPtr pixmap = glamor_get_drawable_pixmap(&window->drawable);\n DrawablePtr drawable = &pixmap->drawable;\n RegionRec dst_region;\n int dx = old_origin.x - window->drawable.x;\n int dy = old_origin.y - window->drawable.y;\n RegionTranslate(src_region, -dx, -dy);\n RegionNull(&dst_region);\n RegionIntersect(&dst_region, &window->borderClip, src_region);\n // pixmap的屏幕起始坐标记录在(screen_x, screen_y)\n if (pixmap->screen_x || pixmap->screen_y)\n RegionTranslate(&dst_region, -pixmap->screen_x, -pixmap->screen_y);\n // 在同一个drawable中拷贝数据时，需考虑内容被覆盖的问题\n // miCopyRegion考虑的拷贝方向（从上往下，从左往右），以避免内容被覆盖的问题\n miCopyRegion(drawable, drawable, 0, &dst_region, dx, dy, glamor_copy, 0, 0);\n RegionUninit(&dst_region);\n}\n\n// 采用opengl进行拷贝，通过reverse和upsidedown指定了拷贝数据时的方向\n// reverse：true为X轴上从右往左拷数据；false为X轴上从左往右拷数据\n// upsidedown：true为Y轴上从网上下拷数据；false为Y轴上从下往上拷数据\nvoid glamor_copy(DrawablePtr src, DrawablePtr dst, GCPtr gc,\n BoxPtr box, int nbox, int dx, int dy,\n Bool reverse, Bool upsidedown, Pixel bitplane, void *closure){\n if (nbox == 0)\n\treturn;\n if (glamor_copy_gl(src, dst, gc, box, nbox, dx, dy, reverse, upsidedown, bitplane, closure))\n return;\n glamor_copy_bail(src, dst, gc, box, nbox, dx, dy, reverse, upsidedown, bitplane, closure);\n}","type":"text"}]},{"type":"heading","attrs":{"level":1},"content":[{"text":"ResizeWindow","type":"text"}]},{"type":"paragraph","content":[{"text":"窗口缩放包含窗口尺寸变化，窗口位置变化等。当窗口尺寸发生变化时，需要计算窗口预留的内容以及子窗口的位置，这些有两个gravity参数标记：bitGravity和winGravity，这些均在miResizeWindow中实现","type":"text"}]},{"type":"bulletList","content":[{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"bitGravity：父窗口尺寸发生变化时，确定父窗口预留的窗口内容，以及在新窗口的放置位置","type":"text"}]}]},{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"winGravity：父窗口尺寸发生变化时，子窗口的winGravity指定了如何计算子窗口的坐标","type":"text"}]}]}]},{"type":"paragraph","content":[{"text":"假设父窗口的尺寸变化为(dw, dh)，坐标变化为(dx,dy)，子窗口的原坐标为(origx,origy)，子窗口的winGravity值如表，可计算其新坐标位置。具体实现在ResizeChildrenWinSize中。","type":"text"}]},{"type":"table","attrs":{"layout":"default","width":760.0,"localId":"f2048e7e-3531-4897-9363-5028d37b714e"},"content":[{"type":"tableRow","content":[{"type":"tableHeader","attrs":{"colspan":1,"rowspan":1,"colwidth":[159.0]},"content":[{"type":"paragraph","marks":[{"type":"alignment","attrs":{"align":"center"}}],"content":[{"text":"winGravity","type":"text","marks":[{"type":"strong"}]}]}]},{"type":"tableHeader","attrs":{"colspan":1,"rowspan":1,"colwidth":[115.0]},"content":[{"type":"paragraph","marks":[{"type":"alignment","attrs":{"align":"center"}}],"content":[{"text":"Deltas","type":"text","marks":[{"type":"strong"}]}]}]},{"type":"tableHeader","attrs":{"colspan":1,"rowspan":1,"colwidth":[485.0]},"content":[{"type":"paragraph","marks":[{"type":"alignment","attrs":{"align":"center"}}],"content":[{"text":"子窗口位置","type":"text","marks":[{"type":"strong"}]}]}]}]},{"type":"tableRow","content":[{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[159.0]},"content":[{"type":"paragraph","content":[{"text":"UnmapGravity","type":"text"}]}]},{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[115.0]},"content":[{"type":"paragraph","content":[{"text":"N/A","type":"text"}]}]},{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[485.0]},"content":[{"type":"paragraph","content":[{"text":"UnmapWindow","type":"text"}]}]}]},{"type":"tableRow","content":[{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[159.0]},"content":[{"type":"paragraph","content":[{"text":"NorthWestGravity","type":"text"}]}]},{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[115.0]},"content":[{"type":"paragraph","content":[{"text":"[0, 0]","type":"text"}]}]},{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[485.0]},"content":[{"type":"paragraph","content":[{"text":"[origx + dx, origy + dy]","type":"text"}]}]}]},{"type":"tableRow","content":[{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[159.0]},"content":[{"type":"paragraph","content":[{"text":"North","type":"text"}]}]},{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[115.0]},"content":[{"type":"paragraph","content":[{"text":"[dw/2, 0]","type":"text"}]}]},{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[485.0]},"content":[{"type":"paragraph","content":[{"text":"[origx + dx + dw/2, origy + dy]","type":"text"}]}]}]},{"type":"tableRow","content":[{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[159.0]},"content":[{"type":"paragraph","content":[{"text":"NorthEast","type":"text"}]}]},{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[115.0]},"content":[{"type":"paragraph","content":[{"text":"[dw, 0]","type":"text"}]}]},{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[485.0]},"content":[{"type":"paragraph","content":[{"text":"[origx + dx + dw, origy + dy]","type":"text"}]}]}]},{"type":"tableRow","content":[{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[159.0]},"content":[{"type":"paragraph","content":[{"text":"West","type":"text"}]}]},{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[115.0]},"content":[{"type":"paragraph","content":[{"text":"[0, dh/2]","type":"text"}]}]},{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[485.0]},"content":[{"type":"paragraph","content":[{"text":"[origx + dx, origy + dy + dh/2]","type":"text"}]}]}]},{"type":"tableRow","content":[{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[159.0]},"content":[{"type":"paragraph","content":[{"text":"Center","type":"text"}]}]},{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[115.0]},"content":[{"type":"paragraph","content":[{"text":"[dw/2, dh/2]","type":"text"}]}]},{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[485.0]},"content":[{"type":"paragraph","content":[{"text":"[origx + dx + dw/2, origy + dy + dh/2]","type":"text"}]}]}]},{"type":"tableRow","content":[{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[159.0]},"content":[{"type":"paragraph","content":[{"text":"East","type":"text"}]}]},{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[115.0]},"content":[{"type":"paragraph","content":[{"text":"[dw, dh/2]","type":"text"}]}]},{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[485.0]},"content":[{"type":"paragraph","content":[{"text":"[origx + dx + dw, origy + dy + dh/2]","type":"text"}]}]}]},{"type":"tableRow","content":[{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[159.0]},"content":[{"type":"paragraph","content":[{"text":"SouthWest","type":"text"}]}]},{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[115.0]},"content":[{"type":"paragraph","content":[{"text":"[0, dh]","type":"text"}]}]},{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[485.0]},"content":[{"type":"paragraph","content":[{"text":"[origx + dx, origy + dy + dh]","type":"text"}]}]}]},{"type":"tableRow","content":[{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[159.0]},"content":[{"type":"paragraph","content":[{"text":"South","type":"text"}]}]},{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[115.0]},"content":[{"type":"paragraph","content":[{"text":"[dw/2, dh]","type":"text"}]}]},{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[485.0]},"content":[{"type":"paragraph","content":[{"text":"[origx + dx + dw/2, origy + dy + dh]","type":"text"}]}]}]},{"type":"tableRow","content":[{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[159.0]},"content":[{"type":"paragraph","content":[{"text":"SouthEast","type":"text"}]}]},{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[115.0]},"content":[{"type":"paragraph","content":[{"text":"[dw, dh]","type":"text"}]}]},{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[485.0]},"content":[{"type":"paragraph","content":[{"text":"[origx + dx + dw, origy + dy + dh]","type":"text"}]}]}]},{"type":"tableRow","content":[{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[159.0]},"content":[{"type":"paragraph","content":[{"text":"StaticGravity","type":"text"}]}]},{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[115.0]},"content":[{"type":"paragraph","content":[{"text":"N/A","type":"text"}]}]},{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[485.0]},"content":[{"type":"paragraph","content":[{"text":"[origx, origy]","type":"text"}]}]}]}]},{"type":"codeBlock","attrs":{"language":"c++"},"content":[{"text":"// 回调函数原型\n// (x, y)相对与父窗口的窗口新坐标，包含边框\n// (width,hight)窗口的新尺寸（宽高），宽高不包括边框\n// sib：窗口的相邻兄弟窗口，及窗口在sib窗口之上，这是窗口在窗口栈的新位置；为空表示窗口置底\nint ResizeWindow(WindowPtr window, int x, int y, unsigned int width, unsigned int height,, WindowPtr sib)","type":"text"}]},{"type":"heading","attrs":{"level":2},"content":[{"text":"xwl_resize_window","type":"text"}]},{"type":"paragraph","content":[{"text":"在非根模式下，额外处理顶级窗口与视口之间的关系，窗口内容在Wayland compositor视口中显示，可能只显示一部分内容。","type":"text"}]},{"type":"codeBlock","attrs":{"language":"c++"},"content":[{"text":"\nvoid xwl_resize_window(WindowPtr window, int x, int y, unsigned int width, unsigned int height, WindowPtr sib){\n ScreenPtr screen = window->drawable.pScreen;\n struct xwl_screen *xwl_screen = xwl_screen_get(screen);\n // 获取xwl_window窗口，window本身或者其祖先窗口对应的xwl_window窗口，存在xwl_window，则比存在一个wl_surface与window对应\n struct xwl_window *xwl_window = xwl_window_from_window(window);\n // 调用compResizeWindow\n screen->ResizeWindow = xwl_screen->ResizeWindow;\n (*screen->ResizeWindow) (window, x, y, width, height, sib);\n xwl_screen->ResizeWindow = screen->ResizeWindow;\n screen->ResizeWindow = xwl_resize_window;\n // window本身有对应的xwl_window窗口，如：窗口管理器创建的装饰窗口\n // 或window是顶层窗口（包括override-redirect和被窗口管理器装饰的顶层窗口）\n if (xwl_window && (xwl_window_get(window) || xwl_window_is_toplevel(window)))\n xwl_window_check_resolution_change_emulation(xwl_window);\n}\n\n// 处理窗口与视口（viewport）的关系\nvoid xwl_window_check_resolution_change_emulation(struct xwl_window *xwl_window){\n struct xwl_emulated_mode emulated_mode;\n struct xwl_output *xwl_output;\n // Wayland compositor支持wp_viewporter_interface接口，获取一个xwl_output和对应的xwl_emulated_mode\n if (xwl_window_should_enable_viewport(xwl_window, &xwl_output, &emulated_mode))\n xwl_window_enable_viewport(xwl_window, xwl_output, &emulated_mode);\n else if (xwl_window_has_viewport_enabled(xwl_window))\n // 找不到与窗口尺寸适配的xwl_emulated_mode，则需禁用原有的视口\n xwl_window_disable_viewport(xwl_window);\n}","type":"text"}]},{"type":"heading","attrs":{"level":2},"content":[{"text":"compResizeWindow","type":"text"}]},{"type":"paragraph","content":[{"text":"回收compWindow中旧的pixmap资源。在compConfigNofity中，由于窗口尺寸的变化，重新分配了窗口的pixmap，原窗口的pixmap缓冲在pOldPixmap中。在miResizeWindow已经利用pOldPixmap将窗口原有内容移至新的pixmap中，此时可销毁旧的pixmap。","type":"text"}]},{"type":"codeBlock","attrs":{"language":"c++"},"content":[{"text":"\nvoid compResizeWindow(WindowPtr window,int x, int y, unsigned int width, unsigned int height, WindowPtr sib){\n ScreenPtr pScreen = pWin->drawable.pScreen;\n CompScreenPtr cs = GetCompScreen(pScreen);\n // 调用miResizeWindow\n pScreen->ResizeWindow = cs->ResizeWindow;\n (*pScreen->ResizeWindow) (pWin, x, y, w, h, pSib);\n cs->ResizeWindow = pScreen->ResizeWindow;\n pScreen->ResizeWindow = compResizeWindow;\n // 是否旧的pixmap，新pixmap可能在compCOnfigNofity中创建\n compFreeOldPixmap(pWin);\n compCheckTree(pScreen);\n}","type":"text"}]},{"type":"heading","attrs":{"level":2},"content":[{"text":"miResizeWindow","type":"text"}]},{"type":"paragraph","content":[{"text":"窗口缩放可能伴随窗口移动，窗口缩放涉及子窗口位置的变动，根据子窗口的winGravity来调整子窗口在窗口中的相对位置（子窗口的布局在新窗口内可能发生变化），子窗口不会缩放，但会窗口区域会截取在父窗口区域内；窗口缩放时涉及原窗口内容在新窗口中的放置位置，由窗口bitGravity来确定，窗口缩小，只能保留原窗口部分内容（保留哪些内容由bitGravity设置）；窗口扩大，可保留原窗口所有内容，新窗口部分区域无内容（或者composite将新窗口内容初始化为该区域的父窗口内容）（初始放置在哪个位置由bitGravity设置）。实现思路为：","type":"text"}]},{"type":"orderedList","attrs":{"order":1},"content":[{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"统计不同winGravity子窗口在原窗口中的可见区域","type":"text"}]}]},{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"标记在父窗口树中被pWin覆盖的窗口和子窗口，包括pWin本身以及子窗口","type":"text"}]}]},{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"更新pWin窗口尺寸和坐标，变为新窗口区域","type":"text"}]}]},{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"更新pWin子窗口的尺寸和坐标，子窗口的坐标变化受其winGravity影响（而非平移），尺寸截取在pWin新窗口内。子窗口的子窗口不受winGravity影响，与其父窗口保存相对位置","type":"text"}]}]},{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"根据pWin的新窗口，计算屏幕可能变化的区域，并计算窗口及子窗口的可见区域，重绘区域等。","type":"text"}]}]},{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"根据pWin的bitGravity计算窗口预留内容在新窗口的起始位置(nx, ny)","type":"text"}]}]},{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"计算原窗口已绘制区域在新窗口有效的区域。新窗口的有效可见区域与原窗口已绘制区域在新窗口的重叠区。并将该区域归至相同gravity的子窗口区域中","type":"text"}]}]},{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"将子窗口原内容迁移至新窗口内","type":"text"}]},{"type":"orderedList","attrs":{"order":1},"content":[{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"确定子窗口的有效区域：计算Gravity分组的原子窗口区域与其在新窗口的重叠区域，该区域为子窗口有效区域","type":"text"}]}]},{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"将子窗口有效区域的内容移至新窗口中","type":"text"}]}]},{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"计算子窗口其它可见区域，用于通知client重绘","type":"text"}]}]}]}]},{"type":"listItem","content":[{"type":"paragraph","content":[{"text":"根据窗口exposed向client发送重绘请求","type":"text"}]}]}]},{"type":"codeBlock","attrs":{"language":"c++"},"content":[{"text":"\nvoid miResizeWindow(WindowPtr pWin, int x, int y, unsigned int w, unsigned int h, WindowPtr pSib){\n WindowPtr pParent;\n Bool WasViewable = (Bool) (pWin->viewable);\n unsigned short width = pWin->drawable.width, height = pWin->drawable.height;\n short oldx = pWin->drawable.x, oldy = pWin->drawable.y;\n int bw = wBorderWidth(pWin);\n short dw, dh;\n DDXPointRec oldpt;\n RegionPtr oldRegion = NULL;\n Bool anyMarked = FALSE;\n ScreenPtr pScreen;\n WindowPtr pFirstChange;\n WindowPtr pChild;\n RegionPtr gravitate[StaticGravity + 1];\n unsigned g;\n int nx, ny; /* destination x,y */\n int newx, newy; /* new inner window position */\n RegionPtr pRegion = NULL;\n RegionPtr destClip; /* portions of destination already written */\n RegionPtr oldWinClip = NULL; /* old clip list for window */\n RegionPtr borderVisible = NullRegion; /* visible area of the border */\n Bool shrunk = FALSE; /* shrunk in an inner dimension */\n Bool moved = FALSE; /* window position changed */\n WindowPtr pLayerWin;\n\n if (!(pParent = pWin->parent))\n return;\n pScreen = pWin->drawable.pScreen;\n newx = pParent->drawable.x + x + bw;\n newy = pParent->drawable.y + y + bw;\n if (WasViewable) {\n anyMarked = FALSE;\n oldRegion = RegionCreate(NullBox, 1); // save the visible region of the window\n RegionCopy(oldRegion, &pWin->winSize);\n // categorize child windows into regions to be moved\n for (g = 0; g <= StaticGravity; g++)\n gravitate[g] = (RegionPtr) NULL;\n // 按照子窗口的winGravity分类，统计每类子窗口的borderClip集合，也即可显示区域（缩放前）\n for (pChild = pWin->firstChild; pChild; pChild = pChild->nextSib) {\n g = pChild->winGravity;\n if (g != UnmapGravity) {\n if (!gravitate[g])\n gravitate[g] = RegionCreate(NullBox, 1);\n RegionUnion(gravitate[g], gravitate[g], &pChild->borderClip);\n }\n else {\n UnmapWindow(pChild, TRUE);\n anyMarked = TRUE;\n }\n }\n // 标记窗口缩放前被pWin遮挡的窗口\n anyMarked |= (*pScreen->MarkOverlappedWindows) (pWin, pWin, &pLayerWin);\n oldWinClip = NULL;\n // bitGravity为ForgetGravity的窗口，每次缩放时需要重绘，因此无需缓冲其原可显示区域（clipList）\n if (pWin->bitGravity != ForgetGravity) {\n oldWinClip = RegionCreate(NullBox, 1);\n RegionCopy(oldWinClip, &pWin->clipList);\n }\n //* if the window is changing size, borderExposed can't be computed correctly without some help.\n if (pWin->drawable.height > h || pWin->drawable.width > w)\n shrunk = TRUE; // 窗口在某个方向缩小\n if (newx != oldx || newy != oldy)\n moved = TRUE; // 伴随窗口移动\n if ((pWin->drawable.height != h || pWin->drawable.width != w) && HasBorder(pWin)) {\n // 存在缩放，且窗口有边框，计算边框可见区域\n borderVisible = RegionCreate(NullBox, 1);\n /* for tiled borders, we punt and draw the whole thing */\n if (pWin->borderIsPixel || !moved) {\n if (shrunk || moved) // 缩小或者移动窗口，边框可能显示在原有的winSize内，因此需要去掉该区域\n RegionSubtract(borderVisible, &pWin->borderClip, &pWin->winSize);\n else // 边框肯定不在winSize区域内\n RegionCopy(borderVisible, &pWin->borderClip);\n }\n }\n }\n // 更新窗口的origin和drawable，设置为新的坐标和尺寸\n pWin->origin.x = x + bw;\n pWin->origin.y = y + bw;\n pWin->drawable.height = h;\n pWin->drawable.width = w;\n\n x = pWin->drawable.x = newx;\n y = pWin->drawable.y = newy;\n\n SetWinSize(pWin);\n SetBorderSize(pWin);\n // 更新子窗口的坐标和尺寸，若有窗口缩放，根据子窗口的winGravity计算新坐标\n dw = (int) w - (int) width;\n dh = (int) h - (int) height;\n ResizeChildrenWinSize(pWin, x - oldx, y - oldy, dw, dh);\n /* let the hardware adjust background and border pixmaps, if any */\n (*pScreen->PositionWindow) (pWin, x, y);\n // 根据窗口栈信息，重排pWin，并返回pWin缩放引起的第一个显示变化的窗口\n pFirstChange = MoveWindowInStack(pWin, pSib);\n if (WasViewable) {\n pRegion = RegionCreate(NullBox, 1);\n if (pLayerWin == pWin) // 标记窗口缩放后与pWin重叠的窗口\n anyMarked |= (*pScreen->MarkOverlappedWindows) (pWin, pFirstChange, NULL);\n else\n anyMarked |= (*pScreen->MarkOverlappedWindows) (pWin, pLayerWin, NULL);\n if (pWin->valdata) {\n pWin->valdata->before.resized = TRUE;\n pWin->valdata->before.borderVisible = borderVisible;\n }\n if (anyMarked)\n (*pScreen->ValidateTree) (pLayerWin->parent, pFirstChange, VTOther);\n // the entire window is trashed unless bitGravity recovers portions of it\n RegionCopy(&pWin->valdata->after.exposed, &pWin->clipList);\n }\n // 计算pWin窗口预留内容区域的新坐标(nx, ny)\n GravityTranslate(x, y, oldx, oldy, dw, dh, pWin->bitGravity, &nx, &ny);\n if (WasViewable) {\n if (HasBorder(pWin)) {\n int offx, offy, dx, dy;\n // kruft to avoid double translates for each gravity\n offx = 0;\n offy = 0;\n for (g = 0; g <= StaticGravity; g++) {\n if (!gravitate[g])\n continue;\n // align winSize to gravitate[g].\n // winSize is in new coordinates, gravitate[g] is still in old coordinates\n // 相同gravity的子窗口大小集合不会超过winSize大小，因此winSize平移后\n // 计算根据子窗口的gravity得到的缩放后的坐标(nx,ny)\n GravityTranslate(x, y, oldx, oldy, dw, dh, g, &nx, &ny);\n dx = (oldx - nx) - offx;\n dy = (oldy - ny) - offy;\n if (dx || dy) {\n // winSize为窗口缩放后的区域，包含了相同gravity的子窗口区域集\n // 平移winSize得到窗口缩放后子窗口在原坐标的窗口区域\n RegionTranslate(&pWin->winSize, dx, dy);\n offx += dx;\n offy += dy;\n }\n // 取交集，计算得到可预留的子窗口内容区域（pWin窗口的缩放可能会导致子窗口内容丢失）\n RegionIntersect(gravitate[g], gravitate[g], &pWin->winSize);\n }\n /* get winSize back where it belongs */\n if (offx || offy)\n RegionTranslate(&pWin->winSize, -offx, -offy);\n }\n // add screen bits to the appropriate bucket\n if (oldWinClip) {\n // clip to new clipList\n RegionCopy(pRegion, oldWinClip);\n // 平移，计算pWin预留窗口内容的新区域。此处好像有bug，当窗口有边框时修改了(nx,ny)，与无边框时值不同\n RegionTranslate(pRegion, nx - oldx, ny - oldy);\n // 取窗口缩放后的clipList的交集，得到pWin已绘制的可见区域\n RegionIntersect(oldWinClip, pRegion, &pWin->clipList);\n // don't step on any gravity bits which will be copied after this region.\n // Note -- this assumes that the regions will be copied in gravity order.\n for (g = pWin->bitGravity + 1; g <= StaticGravity; g++) {\n if (gravitate[g]) // 去掉被原位置子窗口覆盖的区域，以减少计算量\n RegionSubtract(oldWinClip, oldWinClip, gravitate[g]);\n }\n // 还原oldWinClip坐标\n RegionTranslate(oldWinClip, oldx - nx, oldy - ny);\n g = pWin->bitGravity;\n if (!gravitate[g])\n gravitate[g] = oldWinClip;\n else {\n RegionUnion(gravitate[g], gravitate[g], oldWinClip);\n RegionDestroy(oldWinClip);\n }\n }\n // move the bits on the screen\n destClip = NULL;\n for (g = 0; g <= StaticGravity; g++) {\n if (!gravitate[g])\n continue;\n GravityTranslate(x, y, oldx, oldy, dw, dh, g, &nx, &ny);\n oldpt.x = oldx + (x - nx);\n oldpt.y = oldy + (y - ny);\n // Note that gravitate[g] is *translated* by CopyWindow\n // only copy the remaining useful bits\n RegionIntersect(gravitate[g], gravitate[g], oldRegion);\n // clip to not overwrite already copied areas\n if (destClip) {\n // destClip为新坐标区域，需平移至旧坐标区域进行操作\n RegionTranslate(destClip, oldpt.x - x, oldpt.y - y);\n RegionSubtract(gravitate[g], gravitate[g], destClip);\n RegionTranslate(destClip, x - oldpt.x, y - oldpt.y);\n }\n // 窗口平移了，需较原窗口内容拷贝至新位置，不同winGravity的子窗口平移后相对位置有变化\n if (oldpt.x != x || oldpt.y != y || pWin->redirectDraw) {\n // 子窗口的预留内容拷贝至新区域，该函数还将gravitate[g]更新为新坐标区域\n (*pWin->drawable.pScreen->CopyWindow) (pWin, oldpt, gravitate[g]);\n }\n // remove any overwritten bits from the remaining useful bits\n RegionSubtract(oldRegion, oldRegion, gravitate[g]);\n // recompute exposed regions of child windows\n for (pChild = pWin->firstChild; pChild; pChild = pChild->nextSib) {\n if (pChild->winGravity != g)\n continue;\n // 计算子窗口需要重绘的区域（exposed）\n RegionIntersect(pRegion, &pChild->borderClip, gravitate[g]);\n TraverseTree(pChild, miRecomputeExposures, (void *) pRegion);\n }\n // remove the successfully copied regions of the window from its exposed region\n if (g == pWin->bitGravity)\n // pWin的部分区域已包含在gravitate[g]中，因此可从重绘区域中去掉\n RegionSubtract(&pWin->valdata->after.exposed, &pWin->valdata->after.exposed, gravitate[g]);\n if (!destClip)\n destClip = gravitate[g];\n else {\n RegionUnion(destClip, destClip, gravitate[g]);\n RegionDestroy(gravitate[g]);\n }\n }\n RegionDestroy(oldRegion);\n RegionDestroy(pRegion);\n if (destClip)\n RegionDestroy(destClip);\n if (anyMarked) {\n (*pScreen->HandleExposures) (pLayerWin->parent);\n if (pScreen->PostValidateTree)\n (*pScreen->PostValidateTree) (pLayerWin->parent, pFirstChange, VTOther);\n }\n }\n if (pWin->realized)\n WindowsRestructured();\n}","type":"text"}]},{"type":"heading","attrs":{"level":1},"content":[{"text":"附录","type":"text"}]},{"type":"heading","attrs":{"level":2},"content":[{"text":"ConfigureWindow","type":"text"}]},{"type":"codeBlock","attrs":{"language":"c++"},"content":[{"text":"int ConfigureWindow(WindowPtr pWin, Mask mask, XID *vlist, ClientPtr client){\n WindowPtr pSib = NullWindow;\n WindowPtr pParent = pWin->parent;\n Window sibwid = 0;\n Mask index2, tmask;\n XID *pVlist;\n short x, y, beforeX, beforeY;\n unsigned short w = pWin->drawable.width,\n h = pWin->drawable.height, bw = pWin->borderWidth;\n int rc, action, smode = Above;\n // 输入窗口无边框\n if ((pWin->drawable.class == InputOnly) && (mask & CWBorderWidth))\n return BadMatch;\n // 指定了兄弟窗口，但未指定窗口栈掩码（调整窗口栈），改变窗口在窗口栈的顺序\n if ((mask & CWSibling) && !(mask & CWStackMode))\n return BadMatch;\n pVlist = vlist;\n // 计算窗口坐标位置(x,y)，该坐标为父窗口的相对坐标\n if (pParent) {\n x = pWin->drawable.x - pParent->drawable.x - (int) bw;\n y = pWin->drawable.y - pParent->drawable.y - (int) bw;\n }\n else {\n x = pWin->drawable.x;\n y = pWin->drawable.y;\n }\n beforeX = x;\n beforeY = y;\n action = RESTACK_WIN; // 默认为调整栈顺序\n if ((mask & (CWX | CWY)) && (!(mask & (CWHeight | CWWidth)))) {\n GET_INT16(CWX, x);\n GET_INT16(CWY, y);\n action = MOVE_WIN; // 窗口坐标有变化，窗口尺寸不变\n }\n else if (mask & (CWX | CWY | CWWidth | CWHeight)) {\n GET_INT16(CWX, x);\n GET_INT16(CWY, y);\n GET_CARD16(CWWidth, w);\n GET_CARD16(CWHeight, h);\n if (!w || !h) {\n client->errorValue = 0;\n return BadValue;\n }\n action = RESIZE_WIN; // 调整窗口大小，包括位置和尺寸\n }\n // 按照掩码获取请求参数，包括边框大小、兄弟窗口，窗口栈位置等\n tmask = mask & ~ChangeMask;\n while (tmask) {\n index2 = (Mask) lowbit(tmask);\n tmask &= ~index2;\n switch (index2) {\n case CWBorderWidth:\n GET_CARD16(CWBorderWidth, bw);\n break;\n case CWSibling:\n sibwid = (Window) *pVlist;\n pVlist++;\n rc = dixLookupWindow(&pSib, sibwid, client, DixGetAttrAccess);\n if (rc != Success) {\n client->errorValue = sibwid;\n return rc;\n }\n if (pSib->parent != pParent) // 必须为兄弟窗口\n return BadMatch;\n if (pSib == pWin)\n return BadMatch;\n break;\n case CWStackMode:\n GET_CARD8(CWStackMode, smode); // 窗口在窗口栈中的位置\n if ((smode != TopIf) && (smode != BottomIf) &&\n (smode != Opposite) && (smode != Above) && (smode != Below)) {\n client->errorValue = smode;\n return BadValue;\n }\n break;\n default:\n client->errorValue = mask;\n return BadValue;\n }\n }\n // root really can't be reconfigured, so just return\n if (!pParent)\n return Success;\n // Figure out if the window should be moved. Doesn't make the changes to the window if event sent.\n if (mask & CWStackMode) // 计算pWin窗口在窗口栈的位置，窗口放置在返回的pSib窗口之上\n pSib = WhereDoIGoInTheStack(pWin, pSib, pParent->drawable.x + x, pParent->drawable.y + y,\n w + (bw << 1), h + (bw << 1), smode);\n else\n pSib = pWin->nextSib;\n // 重定向ConfigureWindow请求，如发送给窗口管理器处理等（发送ConfigureRequest事件）\n if ((!pWin->overrideRedirect) && (RedirectSend(pParent))) {\n xEvent event = {\n .u.configureRequest.window = pWin->drawable.id,\n .u.configureRequest.sibling = (mask & CWSibling) ? sibwid : None,\n .u.configureRequest.x = x,\n .u.configureRequest.y = y,\n .u.configureRequest.width = w,\n .u.configureRequest.height = h,\n .u.configureRequest.borderWidth = bw,\n .u.configureRequest.valueMask = mask,\n .u.configureRequest.parent = pParent->drawable.id\n };\n event.u.u.type = ConfigureRequest;\n event.u.u.detail = (mask & CWStackMode) ? smode : Above;\n if (MaybeDeliverEventsToClient(pParent, &event, 1, SubstructureRedirectMask, client) == 1)\n return Success;\n }\n if (action == RESIZE_WIN) {\n Bool size_change = (w != pWin->drawable.width) || (h != pWin->drawable.height);\n if (size_change && ((pWin->eventMask | wOtherEventMasks(pWin)) & ResizeRedirectMask)) {\n // 重定向Resize Window，发送ResizeRequest给感兴趣的client\n xEvent eventT = {\n .u.resizeRequest.window = pWin->drawable.id,\n .u.resizeRequest.width = w,\n .u.resizeRequest.height = h\n };\n eventT.u.u.type = ResizeRequest;\n if (MaybeDeliverEventsToClient(pWin, &eventT, 1, ResizeRedirectMask, client) == 1) {\n /* if event is delivered, leave the actual size alone. */\n w = pWin->drawable.width;\n h = pWin->drawable.height;\n size_change = FALSE;\n }\n }\n if (!size_change) {\n if (mask & (CWX | CWY))\n action = MOVE_WIN;\n else if (mask & (CWStackMode | CWBorderWidth))\n action = RESTACK_WIN;\n else /* really nothing to do */\n return (Success);\n }\n }\n\n if (action == RESIZE_WIN)\n goto ActuallyDoSomething;\n if ((mask & CWX) && (x != beforeX))\n goto ActuallyDoSomething;\n if ((mask & CWY) && (y != beforeY))\n goto ActuallyDoSomething;\n if ((mask & CWBorderWidth) && (bw != wBorderWidth(pWin)))\n goto ActuallyDoSomething;\n if (mask & CWStackMode) {\n if (pWin->nextSib != pSib) // 相同，则窗口栈顺序不变\n goto ActuallyDoSomething;\n }\n return Success;\n\n ActuallyDoSomething:\n if (pWin->drawable.pScreen->ConfigNotify) {\n // 通过回调ConfigNotify函数告知扩展协议窗口配置变化\n int ret = (*pWin->drawable.pScreen->ConfigNotify) (pWin, x, y, w, h, bw, pSib);\n if (ret) {\n client->errorValue = 0;\n return ret;\n }\n }\n if (SubStrSend(pWin, pParent)) {\n // 发送ConfigureNotify事件，通知感兴趣的client窗口配置变化\n xEvent event = {\n .u.configureNotify.window = pWin->drawable.id,\n .u.configureNotify.aboveSibling = pSib ? pSib->drawable.id : None,\n .u.configureNotify.x = x,\n .u.configureNotify.y = y,\n .u.configureNotify.width = w,\n .u.configureNotify.height = h,\n .u.configureNotify.borderWidth = bw,\n .u.configureNotify.override = pWin->overrideRedirect\n };\n event.u.u.type = ConfigureNotify;\n DeliverEvents(pWin, &event, 1, NullWindow);\n }\n if (mask & CWBorderWidth) {\n if (action == RESTACK_WIN) {\n action = MOVE_WIN;\n pWin->borderWidth = bw;\n }\n else if ((action == MOVE_WIN) &&\n (beforeX + wBorderWidth(pWin) == x + (int) bw) &&\n (beforeY + wBorderWidth(pWin) == y + (int) bw)) {\n // 窗口边框大小引起的窗口坐标变化，即窗口可绘制区域未变化，且位置不变\n action = REBORDER_WIN;\n (*pWin->drawable.pScreen->ChangeBorderWidth) (pWin, bw);\n }\n else\n pWin->borderWidth = bw; \n }\n if (action == MOVE_WIN)\n (*pWin->drawable.pScreen->MoveWindow) (pWin, x, y, pSib,\n (mask & CWBorderWidth) ? VTOther : VTMove);\n else if (action == RESIZE_WIN)\n (*pWin->drawable.pScreen->ResizeWindow) (pWin, x, y, w, h, pSib);\n else if (mask & CWStackMode)\n ReflectStackChange(pWin, pSib, VTOther);\n if (action != RESTACK_WIN)\n CheckCursorConfinement(pWin);\n return Success;\n}","type":"text"}]},{"type":"heading","attrs":{"level":2},"content":[{"text":"miComputeClips","type":"text"}]},{"type":"codeBlock","attrs":{"language":"c++"},"content":[{"text":"static void miComputeClips(WindowPtr pParent, ScreenPtr pScreen, RegionPtr universe, VTKind kind, RegionPtr exposed) {\n int dx, dy;\n RegionRec childUniverse;\n WindowPtr pChild;\n int oldVis, newVis;\n BoxRec borderSize;\n RegionRec childUnion;\n Bool overlap;\n RegionPtr borderVisible;\n\n // Figure out the new visibility of this window.\n // The extent of the universe should be the same as the extent of the borderSize region. \n // If the window is unobscured, this rectangle will be completely inside the universe\n // (the universe will cover it completely). \n // If the window is completely obscured, none of the universe will cover the rectangle.\n borderSize.x1 = pParent->drawable.x - wBorderWidth(pParent);\n borderSize.y1 = pParent->drawable.y - wBorderWidth(pParent);\n // 坐标要比32K小（16bits）\n dx = (int) pParent->drawable.x + (int) pParent->drawable.width + wBorderWidth(pParent);\n if (dx > 32767) dx = 32767;\n borderSize.x2 = dx;\n dy = (int) pParent->drawable.y + (int) pParent->drawable.height + wBorderWidth(pParent);\n if (dy > 32767) dy = 32767;\n borderSize.y2 = dy;\n\n // In redirected drawing case, reset universe to borderSize\n if (pParent->redirectDraw != RedirectDrawNone) {\n if (TreatAsTransparent(pParent))\n RegionEmpty(universe);\n compSetRedirectBorderClip (pParent, universe);\n RegionCopy(universe, &pParent->borderSize);\n }\n oldVis = pParent->visibility;\n // 计算窗口的可见性，全部可见，部分可见，全不可见。borderSize被universe全包含，则全部可见\n switch (RegionContainsRect(universe, &borderSize)) {\n case rgnIN:\n newVis = VisibilityUnobscured;\n break;\n case rgnPART:\n newVis = VisibilityPartiallyObscured;\n {\n RegionPtr pBounding;\n // shape扩展根据指定的shape边界调整窗口可见性\n if ((pBounding = wBoundingShape(pParent))) {\n switch (miShapedWindowIn(universe, pBounding, &borderSize, pParent->drawable.x, pParent->drawable.y)) {\n case rgnIN:\n newVis = VisibilityUnobscured;\n break;\n case rgnOUT:\n newVis = VisibilityFullyObscured;\n break;\n }\n }\n }\n break;\n default:\n newVis = VisibilityFullyObscured;\n break;\n }\n pParent->visibility = newVis;\n // 可见性有改变，且client关心该窗口可见性变化，则发送VisibilityNotify事件\n if (oldVis != newVis && ((pParent->eventMask | wOtherEventMasks(pParent)) & VisibilityChangeMask))\n SendVisibilityNotify(pParent);\n // 窗口在计算重叠窗口后，可能会有所调整。dx，dy表示起始坐标调整幅度\n dx = pParent->drawable.x - pParent->valdata->before.oldAbsCorner.x;\n dy = pParent->drawable.y - pParent->valdata->before.oldAbsCorner.y;\n\n // avoid computations when dealing with simple operations\n switch (kind) {\n case VTMap:\n case VTStack:\n case VTUnmap:\n break;\n case VTMove:\n if ((oldVis == newVis) && ((oldVis == VisibilityFullyObscured) || (oldVis == VisibilityUnobscured))) {\n pChild = pParent;\n // 深度优先，处理pParent所有子窗口，子窗口需随父窗口移动，无需重绘内容（除了边框）\n while (1) {\n if (pChild->viewable) {\n if (pChild->visibility != VisibilityFullyObscured) {\n // 窗口移动，更新borderClip和clipList区域坐标\n RegionTranslate(&pChild->borderClip, dx, dy);\n RegionTranslate(&pChild->clipList, dx, dy);\n pChild->drawable.serialNumber = NEXT_SERIAL_NUMBER;\n // ClipNotify函数回调：compClipNotify -> xf86XVClipNotify\n if (pScreen->ClipNotify)\n (*pScreen->ClipNotify) (pChild, dx, dy);\n }\n if (pChild->valdata) {\n RegionNull(&pChild->valdata->after.borderExposed);\n if (HasParentRelativeBorder(pChild)) {\n // 有边框，则记录边框暴露区域（borderClip - winSize），4个边框区域\n RegionSubtract(&pChild->valdata->after.borderExposed, &pChild->borderClip, &pChild->winSize);\n }\n // 因可见性没变，不需要重绘\n RegionNull(&pChild->valdata->after.exposed);\n }\n if (pChild->firstChild) {\n pChild = pChild->firstChild;\n continue;\n }\n }\n while (!pChild->nextSib && (pChild != pParent))\n pChild = pChild->parent;\n if (pChild == pParent)\n break;\n pChild = pChild->nextSib;\n }\n return;\n }\n /* fall through */\n default:\n // To calculate exposures correctly, we have to translate the old borderClip and clipList regions \n // to the window's new location so there is a correspondence between pieces of the new and old clipping regions.\n if (dx || dy) {\n // We translate the old clipList because that will be exposed or copied if gravity is right.\n RegionTranslate(&pParent->borderClip, dx, dy);\n RegionTranslate(&pParent->clipList, dx, dy);\n }\n break;\n case VTBroken:\n RegionEmpty(&pParent->borderClip);\n RegionEmpty(&pParent->clipList);\n break;\n }\n\n borderVisible = pParent->valdata->before.borderVisible;\n RegionNull(&pParent->valdata->after.borderExposed);\n RegionNull(&pParent->valdata->after.exposed);\n\n // Since the borderClip must not be clipped by the children, we do the border exposure first...\n // 'universe' is the window's borderClip. \n // To figure the exposures, remove the area that used to be exposed from the new.\n // This leaves a region of pieces that weren't exposed before.\n if (HasBorder(pParent)) {\n if (borderVisible) {\n // when the border changes shape, the old visible portions of the border will be saved by DIX in borderVisible --\n // use that region and destroy it\n\t // 包含边框的区域已显示，去掉该区域\n RegionSubtract(exposed, universe, borderVisible);\n RegionDestroy(borderVisible);\n }\n else {\n // 暴露区域为去掉已绘制的包含边框的区域\n RegionSubtract(exposed, universe, &pParent->borderClip);\n }\n if (HasParentRelativeBorder(pParent) && (dx || dy))\n // 边框需要重绘，（窗口移动且backgroundState == ParentRelative）\n RegionSubtract(&pParent->valdata->after.borderExposed, universe, &pParent->winSize);\n else\n // 在可暴露区域范围内重绘边框，去掉可绘制窗口区域\n RegionSubtract(&pParent->valdata->after.borderExposed, exposed, &pParent->winSize);\n // 缓冲包含边框的可绘制区域\n RegionCopy(&pParent->borderClip, universe);\n\n // To get the right clipList for the parent, and to make doubly sure that no child overlaps the parent's border, \n // we remove the parent's border from the universe before proceeding.\n // 可绘制窗口区域\n RegionIntersect(universe, universe, &pParent->winSize);\n }\n else\n RegionCopy(&pParent->borderClip, universe);\n\n if ((pChild = pParent->firstChild) && pParent->mapped) {\n // 获取子窗口覆盖的区域childUnion，包括边框\n RegionNull(&childUniverse);\n RegionNull(&childUnion);\n if ((pChild->drawable.y < pParent->lastChild->drawable.y) ||\n ((pChild->drawable.y == pParent->lastChild->drawable.y) &&\n (pChild->drawable.x < pParent->lastChild->drawable.x))) {\n for (; pChild; pChild = pChild->nextSib) {\n if (pChild->viewable && !TreatAsTransparent(pChild))\n RegionAppend(&childUnion, &pChild->borderSize);\n }\n }\n else {\n for (pChild = pParent->lastChild; pChild; pChild = pChild->prevSib) {\n if (pChild->viewable && !TreatAsTransparent(pChild))\n RegionAppend(&childUnion, &pChild->borderSize);\n }\n }\n RegionValidate(&childUnion, &overlap);\n // 按照深度优先递归处理子窗口的可剪接区域\n for (pChild = pParent->firstChild; pChild; pChild = pChild->nextSib) {\n if (pChild->viewable) {\n // If the child is viewable, we want to remove its extents from the current universe,\n // but we only re-clip it if it's been marked.\n if (pChild->valdata) {\n // Figure out the new universe from the child's perspective and recurse.\n // 子窗口可绘制区域。所有子窗口可绘制区域universe与窗口大小的交集\n RegionIntersect(&childUniverse, universe, &pChild->borderSize);\n miComputeClips(pChild, pScreen, &childUniverse, kind, exposed);\n }\n // Once the child has been processed, \n // we remove its extents from the current universe, thus denying its space to any other sibling.\n if (overlap && !TreatAsTransparent(pChild))\n // 有子窗口间有重叠，减去pChild窗口大小\n // 窗口树堆叠顺序，确保后处理的子窗口被前处理的子窗口覆盖，因此可视区域可直接减去窗口区域\n RegionSubtract(universe, universe, &pChild->borderSize);\n }\n }\n // 子窗口无重叠，减去所有子窗口的区域，即为父窗口可见区域。universe为最终父窗口可见区域\n if (!overlap)\n RegionSubtract(universe, universe, &childUnion);\n RegionUninit(&childUnion);\n RegionUninit(&childUniverse);\n } /* if any children */\n\n // 'universe' now contains the new clipList for the parent window.\n // To figure the exposure of the window we subtract the old clip from the new, just as for the border.\n if (oldVis == VisibilityFullyObscured || oldVis == VisibilityNotViewable) {\n // 之前被遮挡，现在被暴露，需重绘\n RegionCopy(&pParent->valdata->after.exposed, universe);\n }\n else if (newVis != VisibilityFullyObscured && newVis != VisibilityNotViewable) {\n // 之前有显示区域（clipList），现在只需重绘未显示的可见区域\n RegionSubtract(&pParent->valdata->after.exposed, universe, &pParent->clipList);\n }\n\n /* HACK ALERT - copying contents of regions, instead of regions */\n {\n RegionRec tmp;\n tmp = pParent->clipList;\n // 更新父窗口的可见区域，这些区域已或者将被重绘\n pParent->clipList = *universe;\n // 更改为原有的可剪接区域（clipList）\n *universe = tmp;\n }\n\n pParent->drawable.serialNumber = NEXT_SERIAL_NUMBER;\n // 调用ClipNotify回调，坐标偏移为(dx, dy)\n if (pScreen->ClipNotify)\n (*pScreen->ClipNotify) (pParent, dx, dy);\n}","type":"text"}]},{"type":"heading","attrs":{"level":2},"content":[{"text":"WhereDoIGoInTheStack","type":"text"}]},{"type":"paragraph","content":[{"text":"根据pWin，pSib，smode以及pWin的原始坐标，计算pWin重排位置，返回pWin窗口之下的第一个兄弟窗口","type":"text"}]},{"type":"table","attrs":{"layout":"default","width":760.0,"localId":"ab614ba6-2e62-43d9-872e-d8aa22eee3b6"},"content":[{"type":"tableRow","content":[{"type":"tableHeader","attrs":{"colspan":1,"rowspan":1,"colwidth":[83.0]},"content":[{"type":"paragraph","marks":[{"type":"alignment","attrs":{"align":"center"}}],"content":[{"text":"smode","type":"text","marks":[{"type":"strong"}]}]}]},{"type":"tableHeader","attrs":{"colspan":1,"rowspan":1,"colwidth":[314.0]},"content":[{"type":"paragraph","marks":[{"type":"alignment","attrs":{"align":"center"}}],"content":[{"text":"pSib","type":"text","marks":[{"type":"strong"}]}]}]},{"type":"tableHeader","attrs":{"colspan":1,"rowspan":1,"colwidth":[362.0]},"content":[{"type":"paragraph","marks":[{"type":"alignment","attrs":{"align":"center"}}],"content":[{"text":"NULL","type":"text","marks":[{"type":"strong"}]}]}]}]},{"type":"tableRow","content":[{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[83.0]},"content":[{"type":"paragraph","content":[{"text":"Aboe","type":"text"}]}]},{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[314.0]},"content":[{"type":"paragraph","content":[{"text":"pWin重排在pSib之上","type":"text"}]}]},{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[362.0]},"content":[{"type":"paragraph","content":[{"text":"pWin重排在栈的顶层","type":"text"}]}]}]},{"type":"tableRow","content":[{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[83.0]},"content":[{"type":"paragraph","content":[{"text":"Below","type":"text"}]}]},{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[314.0]},"content":[{"type":"paragraph","content":[{"text":"pWin重排在pSib之下","type":"text"}]}]},{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[362.0]},"content":[{"type":"paragraph","content":[{"text":"pWin重排在栈的底层","type":"text"}]}]}]},{"type":"tableRow","content":[{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[83.0]},"content":[{"type":"paragraph","content":[{"text":"TopIf","type":"text"}]}]},{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[314.0]},"content":[{"type":"paragraph","content":[{"text":"若pSib遮挡了pWin，则pWin重排在栈顶层","type":"text"}]}]},{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[362.0]},"content":[{"type":"paragraph","content":[{"text":"若有兄弟窗口遮挡pWin，则pWin重排在栈顶层","type":"text"}]}]}]},{"type":"tableRow","content":[{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[83.0]},"content":[{"type":"paragraph","content":[{"text":"BottomIf","type":"text"}]}]},{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[314.0]},"content":[{"type":"paragraph","content":[{"text":"若pWin遮挡了pSib，则pWin重排在栈底层","type":"text"}]}]},{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[362.0]},"content":[{"type":"paragraph","content":[{"text":"若pWin遮挡任意兄弟窗口，则pWin重排在栈底层","type":"text"}]}]}]},{"type":"tableRow","content":[{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[83.0]},"content":[{"type":"paragraph","content":[{"text":"Opposite","type":"text"}]}]},{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[314.0]},"content":[{"type":"paragraph","content":[{"text":"若pSib遮挡了pWin，则pWin重排在栈顶层","type":"text"}]},{"type":"paragraph","content":[{"text":"若pWin遮挡了pSib，则pWin重排在栈底层","type":"text"}]}]},{"type":"tableCell","attrs":{"colspan":1,"rowspan":1,"colwidth":[362.0]},"content":[{"type":"paragraph","content":[{"text":"若有兄弟窗口遮挡pWin，则pWin重排在栈顶层","type":"text"}]},{"type":"paragraph","content":[{"text":"若pWin遮挡任意兄弟窗口，则pWin重排在栈底层","type":"text"}]}]}]}]},{"type":"codeBlock","attrs":{"language":"c++"},"content":[{"text":"// 返回新栈中pWin窗口下的第一个兄弟窗口\n// 返回NULL，表示pWin重排在栈低\n// 返回pWin->nextSib，表示栈不变\nstatic WindowPtr WhereDoIGoInTheStack(WindowPtr pWin, WindowPtr pSib,\n short x, short y, unsigned short w, unsigned short h, int smode){\n BoxRec box;\n WindowPtr pHead, pFirst;\n\n if ((pWin == pWin->parent->firstChild) && (pWin == pWin->parent->lastChild))\n return NULL;\n pHead = RealChildHead(pWin->parent);\n pFirst = pHead ? pHead->nextSib : pWin->parent->firstChild;\n box.x1 = x;\n box.y1 = y;\n box.x2 = x + (int) w;\n box.y2 = y + (int) h;\n switch (smode) {\n case Above:\n if (pSib)\n return pSib;\n else if (pWin == pFirst)\n return pWin->nextSib;\n else\n return pFirst;\n case Below:\n if (pSib)\n if (pSib->nextSib != pWin)\n return pSib->nextSib;\n else\n return pWin->nextSib;\n else\n return NullWindow;\n case TopIf:\n if ((!pWin->mapped || (pSib && !pSib->mapped)))\n return pWin->nextSib;\n else if (pSib) {\n if ((IsSiblingAboveMe(pWin, pSib) == Above) &&\n (RegionContainsRect(&pSib->borderSize, &box) != rgnOUT))\n return pFirst;\n else\n return pWin->nextSib;\n }\n else if (AnyWindowOverlapsMe(pWin, pHead, &box))\n return pFirst;\n else\n return pWin->nextSib;\n case BottomIf:\n if ((!pWin->mapped || (pSib && !pSib->mapped)))\n return pWin->nextSib;\n else if (pSib) {\n if ((IsSiblingAboveMe(pWin, pSib) == Below) &&\n (RegionContainsRect(&pSib->borderSize, &box) != rgnOUT))\n return NullWindow;\n else\n return pWin->nextSib;\n }\n else if (IOverlapAnyWindow(pWin, &box))\n return NullWindow;\n else\n return pWin->nextSib;\n case Opposite:\n if ((!pWin->mapped || (pSib && !pSib->mapped)))\n return pWin->nextSib;\n else if (pSib) {\n if (RegionContainsRect(&pSib->borderSize, &box) != rgnOUT) {\n if (IsSiblingAboveMe(pWin, pSib) == Above)\n return pFirst;\n else\n return NullWindow;\n }\n else\n return pWin->nextSib;\n }\n else if (AnyWindowOverlapsMe(pWin, pHead, &box)) {\n /* If I'm occluded, I can't possibly be the first child\n * if (pWin == pWin->parent->firstChild)\n * return pWin->nextSib;\n */\n return pFirst;\n }\n else if (IOverlapAnyWindow(pWin, &box))\n return NullWindow;\n else\n return pWin->nextSib;\n default:\n return pWin->nextSib; // should never happen; make something up.\n }\n}","type":"text"}]}],"version":1}

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