Tables, Nav, Scrolling: fixed scrolling functions and focus tracking with frozen rows and columns. (#5143, #4868, #3692)

docs/CHANGELOG.txt

@@ -42,7 +42,10 @@ Other changes:
 - Fixed cases where CTRL+Tab or Modal can occasionally lead to the creation of ImDrawCmd with
   zero triangles, which would makes the render loop of some backends assert (e.g. Metal with
   debugging, Allegro). (#4857, #5937)
-- Tables, Columns: Fixed cases where empty columns may lead to empty ImDrawCmd. (#4857, #5937)
+- Tables, Nav, Scrolling: fixed scrolling functions and focus tracking with frozen rows and
+  frozen columns. Windows now have a better understanding of outer/inner decoration sizes,
+  which should later lead us toward more flexible uses of menu/status bars. (#5143, #4868, #3692)
+- Tables, Columns: fixed cases where empty columns may lead to empty ImDrawCmd. (#4857, #5937)
 - Inputs, IO: reworked ImGuiMod_Shortcut to redirect to Ctrl/Super at runtime instead of
   compile-time, being consistent with our support for io.ConfigMacOSXBehaviors and making it
   easier for bindings generators to process that value. (#5923, #456)

imgui.cpp

@@ -6467,6 +6467,7 @@ bool ImGui::Begin(const char* name, bool* p_open, ImGuiWindowFlags flags)
         // Apply scrolling
         window->Scroll = CalcNextScrollFromScrollTargetAndClamp(window);
         window->ScrollTarget = ImVec2(FLT_MAX, FLT_MAX);
+        window->DecoInnerSizeX1 = window->DecoInnerSizeY1 = 0.0f;
 
         // DRAWING
 
@@ -9589,7 +9590,7 @@ static float CalcScrollEdgeSnap(float target, float snap_min, float snap_max, fl
 static ImVec2 CalcNextScrollFromScrollTargetAndClamp(ImGuiWindow* window)
 {
     ImVec2 scroll = window->Scroll;
-    ImVec2 decoration_size(window->DecoOuterSizeX1 + window->DecoOuterSizeX2, window->DecoOuterSizeY1 + window->DecoOuterSizeY2);
+    ImVec2 decoration_size(window->DecoOuterSizeX1 + window->DecoInnerSizeX1 + window->DecoOuterSizeX2, window->DecoOuterSizeY1 + window->DecoInnerSizeY1 + window->DecoOuterSizeY2);
     for (int axis = 0; axis < 2; axis++)
     {
         if (window->ScrollTarget[axis] < FLT_MAX)
@@ -9628,6 +9629,8 @@ ImVec2 ImGui::ScrollToRectEx(ImGuiWindow* window, const ImRect& item_rect, ImGui
 {
     ImGuiContext& g = *GImGui;
     ImRect scroll_rect(window->InnerRect.Min - ImVec2(1, 1), window->InnerRect.Max + ImVec2(1, 1));
+    scroll_rect.Min.x = ImMin(scroll_rect.Min.x + window->DecoInnerSizeX1, scroll_rect.Max.x);
+    scroll_rect.Min.y = ImMin(scroll_rect.Min.y + window->DecoInnerSizeY1, scroll_rect.Max.y);
     //GetForegroundDrawList(window)->AddRect(item_rect.Min, item_rect.Max, IM_COL32(255,0,0,255), 0.0f, 0, 5.0f); // [DEBUG]
     //GetForegroundDrawList(window)->AddRect(scroll_rect.Min, scroll_rect.Max, IM_COL32_WHITE); // [DEBUG]
 
@@ -9757,7 +9760,7 @@ void ImGui::SetScrollY(float scroll_y)
 void ImGui::SetScrollFromPosX(ImGuiWindow* window, float local_x, float center_x_ratio)
 {
     IM_ASSERT(center_x_ratio >= 0.0f && center_x_ratio <= 1.0f);
-    window->ScrollTarget.x = IM_FLOOR(local_x - window->DecoOuterSizeX1 + window->Scroll.x); // Convert local position to scroll offset
+    window->ScrollTarget.x = IM_FLOOR(local_x - window->DecoOuterSizeX1 - window->DecoInnerSizeX1 + window->Scroll.x); // Convert local position to scroll offset
     window->ScrollTargetCenterRatio.x = center_x_ratio;
     window->ScrollTargetEdgeSnapDist.x = 0.0f;
 }
@@ -9765,7 +9768,7 @@ void ImGui::SetScrollFromPosX(ImGuiWindow* window, float local_x, float center_x
 void ImGui::SetScrollFromPosY(ImGuiWindow* window, float local_y, float center_y_ratio)
 {
     IM_ASSERT(center_y_ratio >= 0.0f && center_y_ratio <= 1.0f);
-    window->ScrollTarget.y = IM_FLOOR(local_y - window->DecoOuterSizeY1 + window->Scroll.y); // Convert local position to scroll offset
+    window->ScrollTarget.y = IM_FLOOR(local_y - window->DecoOuterSizeY1 - window->DecoInnerSizeY1 + window->Scroll.y); // Convert local position to scroll offset
     window->ScrollTargetCenterRatio.y = center_y_ratio;
     window->ScrollTargetEdgeSnapDist.y = 0.0f;
 }
@@ -13215,8 +13218,8 @@ void ImGui::ShowMetricsWindow(bool* p_open)
             else if (rect_type == TRT_ColumnsClipRect)          { ImGuiTableColumn* c = &table->Columns[n]; return c->ClipRect; }
             else if (rect_type == TRT_ColumnsContentHeadersUsed){ ImGuiTableColumn* c = &table->Columns[n]; return ImRect(c->WorkMinX, table->InnerClipRect.Min.y, c->ContentMaxXHeadersUsed, table->InnerClipRect.Min.y + table_instance->LastFirstRowHeight); } // Note: y1/y2 not always accurate
             else if (rect_type == TRT_ColumnsContentHeadersIdeal){ImGuiTableColumn* c = &table->Columns[n]; return ImRect(c->WorkMinX, table->InnerClipRect.Min.y, c->ContentMaxXHeadersIdeal, table->InnerClipRect.Min.y + table_instance->LastFirstRowHeight); }
-            else if (rect_type == TRT_ColumnsContentFrozen)     { ImGuiTableColumn* c = &table->Columns[n]; return ImRect(c->WorkMinX, table->InnerClipRect.Min.y, c->ContentMaxXFrozen, table->InnerClipRect.Min.y + table_instance->LastFirstRowHeight); }
+            else if (rect_type == TRT_ColumnsContentFrozen)     { ImGuiTableColumn* c = &table->Columns[n]; return ImRect(c->WorkMinX, table->InnerClipRect.Min.y, c->ContentMaxXFrozen, table->InnerClipRect.Min.y + table_instance->LastFrozenHeight); }
-            else if (rect_type == TRT_ColumnsContentUnfrozen)   { ImGuiTableColumn* c = &table->Columns[n]; return ImRect(c->WorkMinX, table->InnerClipRect.Min.y + table_instance->LastFirstRowHeight, c->ContentMaxXUnfrozen, table->InnerClipRect.Max.y); }
+            else if (rect_type == TRT_ColumnsContentUnfrozen)   { ImGuiTableColumn* c = &table->Columns[n]; return ImRect(c->WorkMinX, table->InnerClipRect.Min.y + table_instance->LastFrozenHeight, c->ContentMaxXUnfrozen, table->InnerClipRect.Max.y); }
             IM_ASSERT(0);
             return ImRect();
         }

imgui.h

@@ -23,7 +23,7 @@
 // Library Version
 // (Integer encoded as XYYZZ for use in #if preprocessor conditionals, e.g. '#if IMGUI_VERSION_NUM > 12345')
 #define IMGUI_VERSION               "1.89.2 WIP"
-#define IMGUI_VERSION_NUM           18914
+#define IMGUI_VERSION_NUM           18915
 #define IMGUI_HAS_TABLE
 
 /*

imgui_internal.h

@@ -2250,6 +2250,7 @@ struct IMGUI_API ImGuiWindow
     float                   WindowBorderSize;                   // Window border size at the time of Begin().
     float                   DecoOuterSizeX1, DecoOuterSizeY1;   // Left/Up offsets. Sum of non-scrolling outer decorations (X1 generally == 0.0f. Y1 generally = TitleBarHeight + MenuBarHeight). Locked during Begin().
     float                   DecoOuterSizeX2, DecoOuterSizeY2;   // Right/Down offsets (X2 generally == ScrollbarSize.x, Y2 == ScrollbarSizes.y).
+    float                   DecoInnerSizeX1, DecoInnerSizeY1;   // Applied AFTER/OVER InnerRect. Specialized for Tables as they use specialized form of clipping and frozen rows/columns are inside InnerRect (and not part of regular decoration sizes).
     int                     NameBufLen;                         // Size of buffer storing Name. May be larger than strlen(Name)!
     ImGuiID                 MoveId;                             // == window->GetID("#MOVE")
     ImGuiID                 ChildId;                            // ID of corresponding item in parent window (for navigation to return from child window to parent window)
@@ -2519,9 +2520,10 @@ struct ImGuiTableCellData
 struct ImGuiTableInstanceData
 {
     float                       LastOuterHeight;            // Outer height from last frame
-    float                       LastFirstRowHeight;         // Height of first row from last frame
+    float                       LastFirstRowHeight;         // Height of first row from last frame (FIXME: this is used as "header height" and may be reworked)
+    float                       LastFrozenHeight;           // Height of frozen section from last frame
 
-    ImGuiTableInstanceData()    { LastOuterHeight = LastFirstRowHeight = 0.0f; }
+    ImGuiTableInstanceData()    { LastOuterHeight = LastFirstRowHeight = LastFrozenHeight = 0.0f; }
 };
 
 // FIXME-TABLE: more transient data could be stored in a per-stacked table structure: DrawSplitter, SortSpecs, incoming RowData

imgui_tables.cpp

@@ -1124,6 +1124,13 @@ void ImGui::TableUpdateLayout(ImGuiTable* table)
     if (table->IsSortSpecsDirty && (table->Flags & ImGuiTableFlags_Sortable))
         TableSortSpecsBuild(table);
 
+    // [Part 14] Setup inner window decoration size (for scrolling / nav tracking to properly take account of frozen rows/columns)
+    if (table->FreezeColumnsRequest > 0)
+        table->InnerWindow->DecoInnerSizeX1 = table->Columns[table->DisplayOrderToIndex[table->FreezeColumnsRequest - 1]].MaxX - table->OuterRect.Min.x;
+    if (table->FreezeRowsRequest > 0)
+        table->InnerWindow->DecoInnerSizeY1 = table_instance->LastFrozenHeight;
+    table_instance->LastFrozenHeight = 0.0f;
+
     // Initial state
     ImGuiWindow* inner_window = table->InnerWindow;
     if (table->Flags & ImGuiTableFlags_NoClip)
@@ -1846,10 +1853,11 @@ void ImGui::TableEndRow(ImGuiTable* table)
     if (unfreeze_rows_actual)
     {
         IM_ASSERT(table->IsUnfrozenRows == false);
+        const float y0 = ImMax(table->RowPosY2 + 1, window->InnerClipRect.Min.y);
         table->IsUnfrozenRows = true;
+        TableGetInstanceData(table, table->InstanceCurrent)->LastFrozenHeight = y0 - table->OuterRect.Min.y;
 
         // BgClipRect starts as table->InnerClipRect, reduce it now and make BgClipRectForDrawCmd == BgClipRect
-        float y0 = ImMax(table->RowPosY2 + 1, window->InnerClipRect.Min.y);
         table->BgClipRect.Min.y = table->Bg2ClipRectForDrawCmd.Min.y = ImMin(y0, window->InnerClipRect.Max.y);
         table->BgClipRect.Max.y = table->Bg2ClipRectForDrawCmd.Max.y = window->InnerClipRect.Max.y;
         table->Bg2DrawChannelCurrent = table->Bg2DrawChannelUnfrozen;