layout: add size prediction for initial xdg commits

fixes #4022

src/events/Windows.cpp

@@ -806,7 +806,9 @@ void Events::listener_commitWindow(void* owner, void* data) {
     CWindow* PWINDOW = (CWindow*)owner;
 
     if (!PWINDOW->m_bIsX11 && PWINDOW->m_uSurface.xdg->initial_commit) {
-        wlr_xdg_toplevel_set_size(PWINDOW->m_uSurface.xdg->toplevel, 0, 0);
+        const auto PREDSIZE = g_pLayoutManager->getCurrentLayout()->predictSizeForNewWindow();
+        Debug::log(LOG, "Layout predicts size {} for {}", PREDSIZE, PWINDOW);
+        wlr_xdg_toplevel_set_size(PWINDOW->m_uSurface.xdg->toplevel, PREDSIZE.x, PREDSIZE.y);
         return;
     }
 

src/layout/DwindleLayout.cpp

@@ -127,7 +127,13 @@ void CHyprDwindleLayout::applyNodeDataToWindow(SDwindleNodeData* pNode, bool for
     const auto PWINDOW = pNode->pWindow;
     // get specific gaps and rules for this workspace,
     // if user specified them in config
-    const auto WORKSPACERULE = g_pConfigManager->getWorkspaceRuleFor(g_pCompositor->getWorkspaceByID(PWINDOW->m_iWorkspaceID));
+    const auto WORKSPACERULE = g_pConfigManager->getWorkspaceRuleFor(g_pCompositor->getWorkspaceByID(pNode->workspaceID));
+
+    if (!g_pCompositor->windowExists(PWINDOW)) {
+        Debug::log(ERR, "Node {} holding invalid {}!!", pNode, PWINDOW);
+        onWindowRemovedTiling(PWINDOW);
+        return;
+    }
 
     if (PWINDOW->m_bIsFullscreen && !pNode->ignoreFullscreenChecks)
         return;
@@ -143,13 +149,7 @@ void CHyprDwindleLayout::applyNodeDataToWindow(SDwindleNodeData* pNode, bool for
     auto               gapsIn  = WORKSPACERULE.gapsIn.value_or(*PGAPSIN);
     auto               gapsOut = WORKSPACERULE.gapsOut.value_or(*PGAPSOUT);
 
-    if (!g_pCompositor->windowExists(PWINDOW) || !PWINDOW->m_bIsMapped) {
-        Debug::log(ERR, "Node {} holding invalid {}!!", pNode, PWINDOW);
-        onWindowRemovedTiling(PWINDOW);
-        return;
-    }
-
-    CBox nodeBox = pNode->box;
+    CBox               nodeBox = pNode->box;
     nodeBox.round();
 
     PWINDOW->m_vSize     = nodeBox.size();
@@ -1093,3 +1093,53 @@ void CHyprDwindleLayout::onEnable() {
 void CHyprDwindleLayout::onDisable() {
     m_lDwindleNodesData.clear();
 }
+
+Vector2D CHyprDwindleLayout::predictSizeForNewWindow() {
+    if (!g_pCompositor->m_pLastMonitor)
+        return {};
+
+    // get window candidate
+    CWindow* candidate = g_pCompositor->m_pLastWindow;
+
+    if (!candidate)
+        candidate = g_pCompositor->getFirstWindowOnWorkspace(g_pCompositor->m_pLastMonitor->activeWorkspace);
+
+    // create a fake node
+    SDwindleNodeData node;
+
+    if (!candidate)
+        return g_pCompositor->m_pLastMonitor->vecSize;
+    else {
+        const auto PNODE = getNodeFromWindow(candidate);
+
+        if (!PNODE)
+            return {};
+
+        node         = *PNODE;
+        node.pWindow = nullptr;
+
+        CBox               box = PNODE->box;
+
+        static auto* const PSMARTSPLIT    = (Hyprlang::INT* const*)g_pConfigManager->getConfigValuePtr("dwindle:smart_split");
+        static auto* const PPRESERVESPLIT = (Hyprlang::INT* const*)g_pConfigManager->getConfigValuePtr("dwindle:preserve_split");
+        static auto* const PFLMULT        = (Hyprlang::FLOAT* const*)g_pConfigManager->getConfigValuePtr("dwindle:split_width_multiplier");
+
+        bool               splitTop = false;
+
+        if (**PPRESERVESPLIT == 0 && **PSMARTSPLIT == 0)
+            splitTop = box.h * **PFLMULT > box.w;
+
+        const auto SPLITSIDE = !splitTop;
+
+        if (SPLITSIDE)
+            node.box = {{}, {box.w / 2.0, box.h}};
+        else
+            node.box = {{}, {box.w, box.h / 2.0}};
+
+        // TODO: make this better and more accurate
+
+        return node.box.size();
+    }
+
+    return {};
+}

src/layout/DwindleLayout.hpp

@@ -59,6 +59,7 @@ class CHyprDwindleLayout : public IHyprLayout {
     virtual void                     alterSplitRatio(CWindow*, float, bool);
     virtual std::string              getLayoutName();
     virtual void                     replaceWindowDataWith(CWindow* from, CWindow* to);
+    virtual Vector2D                 predictSizeForNewWindow();
 
     virtual void                     onEnable();
     virtual void                     onDisable();

src/layout/IHyprLayout.cpp

@@ -593,4 +593,8 @@ void IHyprLayout::requestFocusForWindow(CWindow* pWindow) {
     g_pCompositor->focusWindow(pWindow);
 }
 
+Vector2D IHyprLayout::predictSizeForNewWindow() {
+    return Vector2D{};
+}
+
 IHyprLayout::~IHyprLayout() {}

src/layout/IHyprLayout.hpp

@@ -181,6 +181,12 @@ class IHyprLayout {
     */
     virtual void requestFocusForWindow(CWindow*);
 
+    /*
+        Called to predict the size of a newly opened window to send it a configure.
+        Return 0,0 if unpredictable
+    */
+    virtual Vector2D predictSizeForNewWindow();
+
   private:
     Vector2D    m_vBeginDragXY;
     Vector2D    m_vLastDragXY;

src/layout/MasterLayout.cpp

@@ -1459,6 +1459,33 @@ void CHyprMasterLayout::replaceWindowDataWith(CWindow* from, CWindow* to) {
     applyNodeDataToWindow(PNODE);
 }
 
+Vector2D CHyprMasterLayout::predictSizeForNewWindow() {
+    static auto* const PNEWISMASTER = (Hyprlang::INT* const*)g_pConfigManager->getConfigValuePtr("master:new_is_master");
+
+    if (!g_pCompositor->m_pLastMonitor)
+        return {};
+
+    const int NODES = getNodesOnWorkspace(g_pCompositor->m_pLastMonitor->activeWorkspace);
+
+    if (NODES <= 0)
+        return g_pCompositor->m_pLastMonitor->vecSize;
+
+    const auto MASTER = getMasterNodeOnWorkspace(g_pCompositor->m_pLastMonitor->activeWorkspace);
+    if (!MASTER) // wtf
+        return {};
+
+    if (*PNEWISMASTER) {
+        return MASTER->size;
+    } else {
+        const auto SLAVES = NODES - getMastersOnWorkspace(g_pCompositor->m_pLastMonitor->activeWorkspace);
+
+        // TODO: make this better
+        return {g_pCompositor->m_pLastMonitor->vecSize.x - MASTER->size.x, g_pCompositor->m_pLastMonitor->vecSize.y / (SLAVES + 1)};
+    }
+
+    return {};
+}
+
 void CHyprMasterLayout::onEnable() {
     for (auto& w : g_pCompositor->m_vWindows) {
         if (w->m_bIsFloating || !w->m_bIsMapped || w->isHidden())

src/layout/MasterLayout.hpp

@@ -65,6 +65,7 @@ class CHyprMasterLayout : public IHyprLayout {
     virtual void                     alterSplitRatio(CWindow*, float, bool);
     virtual std::string              getLayoutName();
     virtual void                     replaceWindowDataWith(CWindow* from, CWindow* to);
+    virtual Vector2D                 predictSizeForNewWindow();
 
     virtual void                     onEnable();
     virtual void                     onDisable();