Docking: Internal: Added helper for automation to process docking at the mouse level.

imgui.cpp

@@ -10896,11 +10896,11 @@ namespace ImGui
     static void             DockNodeUpdateVisibleFlag(ImGuiDockNode* node);
     static void             DockNodeStartMouseMovingWindow(ImGuiDockNode* node, ImGuiWindow* window);
     static bool             DockNodeIsDropAllowed(ImGuiWindow* host_window, ImGuiWindow* payload_window);
-    static bool             DockNodePreviewDockCalc(ImGuiWindow* host_window, ImGuiDockNode* host_node, ImGuiWindow* payload_window, ImGuiDockPreviewData* preview_data, bool is_explicit_target, bool is_outer_docking);
+    static void             DockNodePreviewDockCalc(ImGuiWindow* host_window, ImGuiDockNode* host_node, ImGuiWindow* payload_window, ImGuiDockPreviewData* preview_data, bool is_explicit_target, bool is_outer_docking);
     static void             DockNodePreviewDockRender(ImGuiWindow* host_window, ImGuiDockNode* host_node, ImGuiWindow* payload_window, const ImGuiDockPreviewData* preview_data);
     static ImRect           DockNodeCalcTabBarRect(const ImGuiDockNode* node);
     static void             DockNodeCalcSplitRects(ImVec2& pos_old, ImVec2& size_old, ImVec2& pos_new, ImVec2& size_new, ImGuiDir dir, ImVec2 size_new_desired);
-    static bool             DockNodeCalcDropRects(const ImRect& parent, ImGuiDir dir, ImRect& out_draw, bool outer_docking);
+    static bool             DockNodeCalcDropRectsAndTestMousePos(const ImRect& parent, ImGuiDir dir, ImRect& out_draw, bool outer_docking, ImVec2* test_mouse_pos);
     static const char*      DockNodeGetHostWindowTitle(ImGuiDockNode* node, char* buf, int buf_size) { ImFormatString(buf, buf_size, "##DockNode_%02X", node->ID); return buf; }
     static int              DockNodeGetDepth(const ImGuiDockNode* node) { int depth = 0; while (node->ParentNode) { node = node->ParentNode; depth++; } return depth; }
     static int              DockNodeGetTabOrder(ImGuiWindow* window);
@@ -11439,6 +11439,25 @@ void ImGui::DockContextProcessUndockNode(ImGuiContext* ctx, ImGuiDockNode* node)
     MarkIniSettingsDirty();
 }
 
+// This is mostly used for automation.
+bool ImGui::DockContextCalcDropPosForDocking(ImGuiWindow* target, ImGuiDockNode* target_node, ImGuiWindow* payload, ImGuiDir split_dir, bool split_outer, ImVec2* out_pos)
+{
+    if (split_outer)
+    {
+        IM_ASSERT(0);
+    }
+    else
+    {
+        ImGuiDockPreviewData split_data;
+        DockNodePreviewDockCalc(target, target_node, payload, &split_data, false, split_outer);
+        if (split_data.DropRectsDraw[split_dir+1].IsInverted())
+            return false;
+        *out_pos = split_data.DropRectsDraw[split_dir+1].GetCenter();
+        return true;
+    }
+    return false;
+}
+
 //-----------------------------------------------------------------------------
 // Docking: ImGuiDockNode
 //-----------------------------------------------------------------------------
@@ -12408,7 +12427,7 @@ void ImGui::DockNodeCalcSplitRects(ImVec2& pos_old, ImVec2& size_old, ImVec2& po
 }
 
 // Retrieve the drop rectangles for a given direction or for the center + perform hit testing.
-bool ImGui::DockNodeCalcDropRects(const ImRect& parent, ImGuiDir dir, ImRect& out_r, bool outer_docking)
+bool ImGui::DockNodeCalcDropRectsAndTestMousePos(const ImRect& parent, ImGuiDir dir, ImRect& out_r, bool outer_docking, ImVec2* test_mouse_pos)
 {
     ImGuiContext& g = *GImGui;
 
@@ -12440,12 +12459,15 @@ bool ImGui::DockNodeCalcDropRects(const ImRect& parent, ImGuiDir dir, ImRect& ou
     else if (dir == ImGuiDir_Left)  { out_r = ImRect(c.x - off.x - hs_h, c.y - hs_w, c.x - off.x + hs_h, c.y + hs_w); }
     else if (dir == ImGuiDir_Right) { out_r = ImRect(c.x + off.x - hs_h, c.y - hs_w, c.x + off.x + hs_h, c.y + hs_w); }
 
+    if (test_mouse_pos == NULL)
+        return false;
+
     ImRect hit_r = out_r;
     if (!outer_docking)
     {
         // Custom hit testing for the 5-way selection, designed to reduce flickering when moving diagonally between sides
         hit_r.Expand(ImFloor(hs_w * 0.30f));
-        ImVec2 mouse_delta = (g.IO.MousePos - c);
+        ImVec2 mouse_delta = (*test_mouse_pos - c);
         float mouse_delta_len2 = ImLengthSqr(mouse_delta);
         float r_threshold_center = hs_w * 1.4f;
         float r_threshold_sides = hs_w * (1.4f + 1.2f);
@@ -12454,14 +12476,13 @@ bool ImGui::DockNodeCalcDropRects(const ImRect& parent, ImGuiDir dir, ImRect& ou
         if (mouse_delta_len2 < r_threshold_sides * r_threshold_sides)
             return (dir == ImGetDirQuadrantFromDelta(mouse_delta.x, mouse_delta.y));
     }
-    return hit_r.Contains(g.IO.MousePos);
+    return hit_r.Contains(*test_mouse_pos);
 }
 
 // host_node may be NULL if the window doesn't have a DockNode already.
-static bool ImGui::DockNodePreviewDockCalc(ImGuiWindow* host_window, ImGuiDockNode* host_node, ImGuiWindow* root_payload, ImGuiDockPreviewData* data, bool is_explicit_target, bool is_outer_docking)
+static void ImGui::DockNodePreviewDockCalc(ImGuiWindow* host_window, ImGuiDockNode* host_node, ImGuiWindow* root_payload, ImGuiDockPreviewData* data, bool is_explicit_target, bool is_outer_docking)
 {
     ImGuiContext& g = *GImGui;
-    IM_ASSERT(g.CurrentWindow == host_window);   // Because we rely on font size to calculate tab sizes
 
     // There is an edge case when docking into a dockspace which only has inactive nodes.
     // In this case DockNodeTreeFindNodeByPos() will have selected a leaf node which is inactive. 
@@ -12503,7 +12524,7 @@ static bool ImGui::DockNodePreviewDockCalc(ImGuiWindow* host_window, ImGuiDockNo
                 continue;
             if (dir != ImGuiDir_None && !data->IsSidesAvailable)
                 continue;
-            if (DockNodeCalcDropRects(data->FutureNode.Rect(), (ImGuiDir)dir, data->DropRectsDraw[dir+1], is_outer_docking))
+            if (DockNodeCalcDropRectsAndTestMousePos(data->FutureNode.Rect(), (ImGuiDir)dir, data->DropRectsDraw[dir+1], is_outer_docking, &g.IO.MousePos))
             {
                 data->SplitDir = (ImGuiDir)dir;
                 data->IsSplitDirExplicit = true;
@@ -12531,13 +12552,12 @@ static bool ImGui::DockNodePreviewDockCalc(ImGuiWindow* host_window, ImGuiDockNo
         data->FutureNode.Size = size_new;
         data->SplitRatio = (split_dir == ImGuiDir_Right || split_dir == ImGuiDir_Down) ? (1.0f - split_ratio) : (split_ratio);
     }
-
-    return data->IsSplitDirExplicit;
 }
 
 static void ImGui::DockNodePreviewDockRender(ImGuiWindow* host_window, ImGuiDockNode* host_node, ImGuiWindow* root_payload, const ImGuiDockPreviewData* data)
 {
     ImGuiContext& g = *GImGui;
+    IM_ASSERT(g.CurrentWindow == host_window);   // Because we rely on font size to calculate tab sizes
 
     // With this option, we only display the preview on the target viewport, and the payload viewport is made transparent.
     // To compensate for the single layer obstructed by the payload, we'll increase the alpha of the preview nodes.
@@ -13684,8 +13704,11 @@ void ImGui::BeginAsDockableDragDropTarget(ImGuiWindow* window)
             ImGuiDockPreviewData* split_data = &split_inner;
             if (node && (node->ParentNode || node->IsCentralNode()))
                 if (ImGuiDockNode* root_node = DockNodeGetRootNode(node))
-                    if (DockNodePreviewDockCalc(window, root_node, payload_window, &split_outer, is_explicit_target, true))
+                {
+                    DockNodePreviewDockCalc(window, root_node, payload_window, &split_outer, is_explicit_target, true);
+                    if (split_outer.IsSplitDirExplicit)
                         split_data = &split_outer;
+                }
             DockNodePreviewDockCalc(window, node, payload_window, &split_inner, is_explicit_target, false);
             if (split_data == &split_outer)
                 split_inner.IsDropAllowed = false;

imgui_internal.h

@@ -1678,6 +1678,7 @@ namespace ImGui
     IMGUI_API void          DockContextQueueDock(ImGuiContext* ctx, ImGuiWindow* target, ImGuiDockNode* target_node, ImGuiWindow* payload, ImGuiDir split_dir, float split_ratio, bool split_outer);
     IMGUI_API void          DockContextQueueUndockWindow(ImGuiContext* ctx, ImGuiWindow* window);
     IMGUI_API void          DockContextQueueUndockNode(ImGuiContext* ctx, ImGuiDockNode* node);
+    IMGUI_API bool          DockContextCalcDropPosForDocking(ImGuiWindow* target, ImGuiDockNode* target_node, ImGuiWindow* payload, ImGuiDir split_dir, bool split_outer, ImVec2* out_pos);
     inline ImGuiDockNode*   DockNodeGetRootNode(ImGuiDockNode* node) { while (node->ParentNode) node = node->ParentNode; return node; }
     IMGUI_API void          BeginDocked(ImGuiWindow* window, bool* p_open);
     IMGUI_API void          BeginAsDockableDragDropSource(ImGuiWindow* window);