ColorPicker: Fixed shading of S/V triangle in Hue Wheel mode. (#6254, #5200)

Amend f6460970

docs/CHANGELOG.txt

@@ -46,6 +46,7 @@ Other changes:
   be desirable to take advantage of this trick. (#4714)
 - Drag, Sliders: Fixed parsing of text input when '+' or '#' format flags are used
   in the format string. (#6259) [@idbrii]
+- ColorEdit: Fixed shading of S/V triangle in Hue Wheel mode. (#5200, #6254) [@jamesthomasgriffin]
 - IO: Fixed support for calling io.AddXXXX functions fron inactive context (wrongly
   advertised as supported in 1.89.4). (#6199, #6256, #5856) [@cfillion]
 - Backends: OpenGL3: Fixed GL loader crash when GL_VERSION returns NULL. (#6154, #4445, #3530)

imgui_widgets.cpp

@@ -5624,13 +5624,10 @@ bool ImGui::ColorPicker4(const char* label, float col[4], ImGuiColorEditFlags fl
         ImVec2 trb = wheel_center + ImRotate(triangle_pb, cos_hue_angle, sin_hue_angle);
         ImVec2 trc = wheel_center + ImRotate(triangle_pc, cos_hue_angle, sin_hue_angle);
         ImVec2 uv_white = GetFontTexUvWhitePixel();
-        draw_list->PrimReserve(6, 6);
+        draw_list->PrimReserve(3, 3);
         draw_list->PrimVtx(tra, uv_white, hue_color32);
-        draw_list->PrimVtx(trb, uv_white, hue_color32);
-        draw_list->PrimVtx(trc, uv_white, col_white);
-        draw_list->PrimVtx(tra, uv_white, 0);
         draw_list->PrimVtx(trb, uv_white, col_black);
-        draw_list->PrimVtx(trc, uv_white, 0);
+        draw_list->PrimVtx(trc, uv_white, col_white);
         draw_list->AddTriangle(tra, trb, trc, col_midgrey, 1.5f);
         sv_cursor_pos = ImLerp(ImLerp(trc, tra, ImSaturate(S)), trb, ImSaturate(1 - V));
     }