Tables: Fixed positioning of Sort icon on right-most column with some settings (not resizable + no borders). (#4918).

docs/CHANGELOG.txt

@@ -105,6 +105,7 @@ Other Changes:
   which would makes the draw operation of some backends assert (e.g. Metal with debugging). (#4857)
 - Tables, ImDrawListSplitter: Fixed erroneously stripping trailing ImDrawList::AddCallback() when submitted in
   last column or last channel and when there are no other drawing operation. (#4843, #4844) [@hoffstadt]
+- Tables: Fixed positioning of Sort icon on right-most column with some settings (not resizable + no borders). (#4918).
 - Sliders, Drags: Fixed text input of values with a leading sign, common when using a format enforcing sign. (#4917)
 - Platform IME: changed io.ImeSetInputScreenPosFn() to io.SetPlatformImeDataFn() API,
   now taking a ImGuiPlatformImeData structure which we can more easily extend in the future.

imgui_internal.h

@@ -2331,7 +2331,7 @@ struct IMGUI_API ImGuiTable
     ImRect                      InnerRect;                  // InnerRect but without decoration. As with OuterRect, for non-scrolling tables, InnerRect.Max.y is
     ImRect                      WorkRect;
     ImRect                      InnerClipRect;
-    ImRect                      BgClipRect;                 // We use this to cpu-clip cell background color fill
+    ImRect                      BgClipRect;                 // We use this to cpu-clip cell background color fill, evolve during the frame as we cross frozen rows boundaries
     ImRect                      Bg0ClipRectForDrawCmd;      // Actual ImDrawCmd clip rect for BG0/1 channel. This tends to be == OuterWindow->ClipRect at BeginTable() because output in BG0/BG1 is cpu-clipped
     ImRect                      Bg2ClipRectForDrawCmd;      // Actual ImDrawCmd clip rect for BG2 channel. This tends to be a correct, tight-fit, because output to BG2 are done by widgets relying on regular ClipRect.
     ImRect                      HostClipRect;               // This is used to check if we can eventually merge our columns draw calls into the current draw call of the current window.

imgui_tables.cpp

@@ -1569,18 +1569,21 @@ ImGuiTableColumnFlags ImGui::TableGetColumnFlags(int column_n)
 
 // Return the cell rectangle based on currently known height.
 // - Important: we generally don't know our row height until the end of the row, so Max.y will be incorrect in many situations.
-//   The only case where this is correct is if we provided a min_row_height to TableNextRow() and don't go below it.
+//   The only case where this is correct is if we provided a min_row_height to TableNextRow() and don't go below it, or in TableEndRow() when we locked that height.
 // - Important: if ImGuiTableFlags_PadOuterX is set but ImGuiTableFlags_PadInnerX is not set, the outer-most left and right
 //   columns report a small offset so their CellBgRect can extend up to the outer border.
+//   FIXME: But the rendering code in TableEndRow() nullifies that with clamping required for scrolling.
 ImRect ImGui::TableGetCellBgRect(const ImGuiTable* table, int column_n)
 {
     const ImGuiTableColumn* column = &table->Columns[column_n];
     float x1 = column->MinX;
     float x2 = column->MaxX;
-    if (column->PrevEnabledColumn == -1)
-        x1 -= table->CellSpacingX1;
-    if (column->NextEnabledColumn == -1)
-        x2 += table->CellSpacingX2;
+    //if (column->PrevEnabledColumn == -1)
+    //    x1 -= table->OuterPaddingX;
+    //if (column->NextEnabledColumn == -1)
+    //    x2 += table->OuterPaddingX;
+    x1 = ImMax(x1, table->WorkRect.Min.x);
+    x2 = ImMin(x2, table->WorkRect.Max.x);
     return ImRect(x1, table->RowPosY1, x2, table->RowPosY2);
 }
 
@@ -1797,10 +1800,12 @@ void ImGui::TableEndRow(ImGuiTable* table)
             ImGuiTableCellData* cell_data_end = &table->RowCellData[table->RowCellDataCurrent];
             for (ImGuiTableCellData* cell_data = &table->RowCellData[0]; cell_data <= cell_data_end; cell_data++)
             {
+                // As we render the BG here we need to clip things (for layout we would not)
+                // FIXME: This cancels the OuterPadding addition done by TableGetCellBgRect(), need to keep it while rendering correctly while scrolling.
                 const ImGuiTableColumn* column = &table->Columns[cell_data->Column];
                 ImRect cell_bg_rect = TableGetCellBgRect(table, cell_data->Column);
                 cell_bg_rect.ClipWith(table->BgClipRect);
-                cell_bg_rect.Min.x = ImMax(cell_bg_rect.Min.x, column->ClipRect.Min.x);     // So that first column after frozen one gets clipped
+                cell_bg_rect.Min.x = ImMax(cell_bg_rect.Min.x, column->ClipRect.Min.x);     // So that first column after frozen one gets clipped when scrolling
                 cell_bg_rect.Max.x = ImMin(cell_bg_rect.Max.x, column->MaxX);
                 window->DrawList->AddRectFilled(cell_bg_rect.Min, cell_bg_rect.Max, cell_data->BgColor);
             }