ImDrawList: Added missing early-out in AddPolyline() and AddConvexPolyFilled() when color alpha is zero. Window: Avoid rendering shapes for hidden resize grips.

docs/CHANGELOG.txt

@@ -37,17 +37,20 @@ HOW TO UPDATE?
 
 All changes:
 
+- Window: Avoid rendering shapes for hidden resize grips.
 - Tables: Raised max Columns count from 64 to 512. (#6094, #5305, #4876, #3572)
   The previous limit was due to using 64-bit integers but we moved to bits-array
   and tweaked the system enough to ensure no performance loss.
 - Text: Fixed layouting of wrapped-text block skipping successive empty lines,
   regression from the fix in 1.89.2. (#5720, #5919)
-- Text: Fix clipping of single-character "..." ellipsis (U+2026 or U+0085) when font
+- Text: Fixed clipping of single-character "..." ellipsis (U+2026 or U+0085) when font
   is scaled. Scaling wasn't taken into account, leading to ellipsis character straying
   slightly out of its expected boundaries. (#2775)
 - Text: Tweaked rendering of three-dots "..." ellipsis variant. (#2775, #4269)
 - Menus: Fixed layout of MenuItem()/BeginMenu() when label contains a '\n'. (#6116) [@imkcy9]
 - PlotHistogram, PlotLines: Passing negative sizes honor alignment like other widgets.
+- ImDrawList: Added missing early-out in AddPolyline() and AddConvexPolyFilled() when
+  color alpha is zero.
 
 
 -----------------------------------------------------------------------

imgui.cpp

@@ -5810,12 +5810,15 @@ void ImGui::RenderWindowDecorations(ImGuiWindow* window, const ImRect& title_bar
         {
             for (int resize_grip_n = 0; resize_grip_n < resize_grip_count; resize_grip_n++)
             {
+                const ImU32 col = resize_grip_col[resize_grip_n];
+                if ((col & IM_COL32_A_MASK) == 0)
+                    continue;
                 const ImGuiResizeGripDef& grip = resize_grip_def[resize_grip_n];
                 const ImVec2 corner = ImLerp(window->Pos, window->Pos + window->Size, grip.CornerPosN);
                 window->DrawList->PathLineTo(corner + grip.InnerDir * ((resize_grip_n & 1) ? ImVec2(window_border_size, resize_grip_draw_size) : ImVec2(resize_grip_draw_size, window_border_size)));
                 window->DrawList->PathLineTo(corner + grip.InnerDir * ((resize_grip_n & 1) ? ImVec2(resize_grip_draw_size, window_border_size) : ImVec2(window_border_size, resize_grip_draw_size)));
                 window->DrawList->PathArcToFast(ImVec2(corner.x + grip.InnerDir.x * (window_rounding + window_border_size), corner.y + grip.InnerDir.y * (window_rounding + window_border_size)), window_rounding, grip.AngleMin12, grip.AngleMax12);
-                window->DrawList->PathFillConvex(resize_grip_col[resize_grip_n]);
+                window->DrawList->PathFillConvex(col);
             }
         }
 

imgui_draw.cpp

@@ -706,7 +706,7 @@ void ImDrawList::PrimQuadUV(const ImVec2& a, const ImVec2& b, const ImVec2& c, c
 // We avoid using the ImVec2 math operators here to reduce cost to a minimum for debug/non-inlined builds.
 void ImDrawList::AddPolyline(const ImVec2* points, const int points_count, ImU32 col, ImDrawFlags flags, float thickness)
 {
-    if (points_count < 2)
+    if (points_count < 2 || (col & IM_COL32_A_MASK) == 0)
         return;
 
     const bool closed = (flags & ImDrawFlags_Closed) != 0;
@@ -964,7 +964,7 @@ void ImDrawList::AddPolyline(const ImVec2* points, const int points_count, ImU32
 // - Filled shapes must always use clockwise winding order. The anti-aliasing fringe depends on it. Counter-clockwise shapes will have "inward" anti-aliasing.
 void ImDrawList::AddConvexPolyFilled(const ImVec2* points, const int points_count, ImU32 col)
 {
-    if (points_count < 3)
+    if (points_count < 3 || (col & IM_COL32_A_MASK) == 0)
         return;
 
     const ImVec2 uv = _Data->TexUvWhitePixel;