Selectable: Fixed honoring style.SelectableTextAlign with unspecified size. (ocornut#2347, ocornut#2601)

Author: ocornut

docs/CHANGELOG.txt

@@ -45,6 +45,7 @@ Other Changes:
   when the menu is not open. (#3030)
 - InputText: Fixed password fields displaying ASCII spaces as blanks instead of using the '*'
   glyph. (#2149, #515)
+- Selectable: Fixed honoring style.SelectableTextAlign with unspecified size. (#2347, #2601)
 - Scrolling: Fixed scrolling centering API leading to non-integer scrolling values and initial
   cursor position. This would often get fixed after the fix item submission, but using the
   ImGuiListClipper as the first thing after Begin() could largely break size calculations. (#3073)

docs/TODO.txt

@@ -223,6 +223,7 @@ It's mostly a bunch of personal notes, probably incomplete. Feel free to query i
  - menus: menu-bar: main menu-bar could affect clamping of windows position (~ akin to modifying DisplayMin)
  - menus: hovering from menu to menu on a menu-bar has 1 frame without any menu, which is a little annoying. ideally either 0 either longer.
  - menus: could merge draw call in most cases (how about storing an optional aabb in ImDrawCmd to move the burden of merging in a single spot).
+ - menus: would be nice if the Selectable() supported horizontal alignment (must be given the equivalent of WorkRect.Max.x matching the position of the shortcut column)
 
  - tree node: add treenode/treepush int variants? not there because (void*) cast from int warns on some platforms/settings?
  - tree node: try to apply scrolling at time of TreePop() if node was just opened and end of node is past scrolling limits?

imgui_widgets.cpp

@@ -5583,31 +5583,33 @@ bool ImGui::Selectable(const char* label, bool selected, ImGuiSelectableFlags fl
     float max_x = (flags & ImGuiSelectableFlags_SpanAllColumns) ? GetWindowContentRegionMax().x + window->Pos.x : GetContentRegionMaxAbs().x;
     float w_draw = ImMax(label_size.x, max_x - window_padding.x - pos.x);
     ImVec2 size_draw((size_arg.x != 0 && !(flags & ImGuiSelectableFlags_DrawFillAvailWidth)) ? size_arg.x : w_draw, size.y);
-    ImRect bb(pos, pos + size_draw);
+
+    ImRect bb_align(pos, pos + size_draw);
     if (size_arg.x == 0.0f || (flags & ImGuiSelectableFlags_DrawFillAvailWidth))
-        bb.Max.x += window_padding.x;
+        bb_align.Max.x += window_padding.x;
 
     // Selectables are meant to be tightly packed together with no click-gap, so we extend the box to cover spacing between selectable.
+    ImRect bb_enlarged = bb_align;
     const float spacing_x = style.ItemSpacing.x;
     const float spacing_y = style.ItemSpacing.y;
     const float spacing_L = IM_FLOOR(spacing_x * 0.50f);
     const float spacing_U = IM_FLOOR(spacing_y * 0.50f);
-    bb.Min.x -= spacing_L;
-    bb.Min.y -= spacing_U;
-    bb.Max.x += (spacing_x - spacing_L);
-    bb.Max.y += (spacing_y - spacing_U);
+    bb_enlarged.Min.x -= spacing_L;
+    bb_enlarged.Min.y -= spacing_U;
+    bb_enlarged.Max.x += (spacing_x - spacing_L);
+    bb_enlarged.Max.y += (spacing_y - spacing_U);
 
     bool item_add;
     if (flags & ImGuiSelectableFlags_Disabled)
     {
         ImGuiItemFlags backup_item_flags = window->DC.ItemFlags;
         window->DC.ItemFlags |= ImGuiItemFlags_Disabled | ImGuiItemFlags_NoNavDefaultFocus;
-        item_add = ItemAdd(bb, id);
+        item_add = ItemAdd(bb_enlarged, id);
         window->DC.ItemFlags = backup_item_flags;
     }
     else
     {
-        item_add = ItemAdd(bb, id);
+        item_add = ItemAdd(bb_enlarged, id);
     }
     if (!item_add)
     {
@@ -5630,7 +5632,7 @@ bool ImGui::Selectable(const char* label, bool selected, ImGuiSelectableFlags fl
 
     const bool was_selected = selected;
     bool hovered, held;
-    bool pressed = ButtonBehavior(bb, id, &hovered, &held, button_flags);
+    bool pressed = ButtonBehavior(bb_enlarged, id, &hovered, &held, button_flags);
 
     // Update NavId when clicking or when Hovering (this doesn't happen on most widgets), so navigation can be resumed with gamepad/keyboard
     if (pressed || (hovered && (flags & ImGuiSelectableFlags_SetNavIdOnHover)))
@@ -5657,21 +5659,22 @@ bool ImGui::Selectable(const char* label, bool selected, ImGuiSelectableFlags fl
     if (hovered || selected)
     {
         const ImU32 col = GetColorU32((held && hovered) ? ImGuiCol_HeaderActive : hovered ? ImGuiCol_HeaderHovered : ImGuiCol_Header);
-        RenderFrame(bb.Min, bb.Max, col, false, 0.0f);
-        RenderNavHighlight(bb, id, ImGuiNavHighlightFlags_TypeThin | ImGuiNavHighlightFlags_NoRounding);
+        RenderFrame(bb_enlarged.Min, bb_enlarged.Max, col, false, 0.0f);
+        RenderNavHighlight(bb_enlarged, id, ImGuiNavHighlightFlags_TypeThin | ImGuiNavHighlightFlags_NoRounding);
     }
 
     if ((flags & ImGuiSelectableFlags_SpanAllColumns) && window->DC.CurrentColumns)
         PopColumnsBackground();
 
     if (flags & ImGuiSelectableFlags_Disabled) PushStyleColor(ImGuiCol_Text, style.Colors[ImGuiCol_TextDisabled]);
-    RenderTextClipped(bb_inner.Min, bb_inner.Max, label, NULL, &label_size, style.SelectableTextAlign, &bb);
+    RenderTextClipped(bb_align.Min, bb_align.Max, label, NULL, &label_size, style.SelectableTextAlign, &bb_enlarged);
     if (flags & ImGuiSelectableFlags_Disabled) PopStyleColor();
 
     // Automatically close popups
     if (pressed && (window->Flags & ImGuiWindowFlags_Popup) && !(flags & ImGuiSelectableFlags_DontClosePopups) && !(window->DC.ItemFlags & ImGuiItemFlags_SelectableDontClosePopup))
         CloseCurrentPopup();
 
+    //if (g.IO.KeyCtrl) { window->DrawList->AddRect(bb_align.Min, bb_align.Max, IM_COL32(0, 255, 0, 255)); }
     IMGUI_TEST_ENGINE_ITEM_INFO(id, label, window->DC.ItemFlags);
     return pressed;
 }