ColorEdit4, ColorPicker4: added support for ImGuiItemFlags_MixedValue. (#5518, #5677, #6865)

docs/CHANGELOG.txt

@@ -74,8 +74,9 @@ Other Changes:
     hasn't been owned by another items. This is more correct and also necessary
     to avoid Drags/Sliders cancelling also triggering a cancel menu. (#8564, #9534)
 - Misc:
-  - Added `ImGuiItemFlags_MixedValue` flag for representing mixed/indeterminate values
+  - Added `ImGuiItemFlags_MixedValue` flag for representing mixed/indeterminate values.
-    in Checkbox(), RadioButton(), DragXXX(), SliderXXX(), InputXXX(), Combo() functions.
+    Supported by: Checkbox(), RadioButton(), DragXXX(), SliderXXX(), InputXXX(), ColorXXX()
+    and Combo() functions.
     The scoped flag is designed for usage by advanced property editors. (#5518, #5677, #6865)
   - Fixed `GetBackgroundDrawList()`/`GetForegroundDrawList()` not being properly reset
     every frame when cumulated session time is very large (e.g. a few days). [@lailoken]

imgui_demo.cpp

@@ -2085,9 +2085,9 @@ static void DemoWindowWidgetsMixedValues()
         ImGui::InputFloat("item 1", &items[1]);
         ImGui::InputFloat("item 2", &items[2]);
 
-        // Demonstrate Checkbox()
+        // Demonstrate Checkbox(), RadioButton(), Combo(), ColorEdit4()
-        // (this is automatically used by e.g. CheckboxFlags())
         ImGui::SeparatorText("Others Widgets");
+        ImGui::Text("(note: edits are not applied in this demo)"); // <-- Would need more state tracking.
         bool b_on = true, b_off = false;
         ImGui::Checkbox("Checkbox On", &b_on);
         ImGui::Checkbox("Checkbox Off", &b_off);
@@ -2098,6 +2098,8 @@ static void DemoWindowWidgetsMixedValues()
         ImGui::RadioButton("RadioButton Mixed##2", true); // Showing 2 radio buttons makes the example more clear
         int combo_idx = 0;
         ImGui::Combo("Combo", &combo_idx, "One\0Two\0Three\0");
+        ImVec4 color(0.5f, 0.5f, 0.5f, 0.5f);
+        ImGui::ColorEdit4("ColorEdit4", &color.x);
         ImGui::PopItemFlag();
 
         ImGui::TreePop();

imgui_widgets.cpp

@@ -6058,7 +6058,9 @@ bool ImGui::ColorEdit4(const char* label, float col[4], ImGuiColorEditFlags flag
                 ImGuiColorEditFlags picker_flags_to_forward = ImGuiColorEditFlags_DataTypeMask_ | ImGuiColorEditFlags_PickerMask_ | ImGuiColorEditFlags_InputMask_ | ImGuiColorEditFlags_HDR | ImGuiColorEditFlags_NoAlpha | ImGuiColorEditFlags_AlphaBar;
                 ImGuiColorEditFlags picker_flags = (flags_untouched & picker_flags_to_forward) | ImGuiColorEditFlags_DisplayMask_ | ImGuiColorEditFlags_NoLabel | ImGuiColorEditFlags_AlphaPreviewHalf;
                 SetNextItemWidth(square_sz * 12.0f); // Use 256 + bar sizes?
+                PushItemFlag(ImGuiItemFlags_MixedValue, false);
                 value_changed |= ColorPicker4("##picker", col, picker_flags, &g.ColorPickerRef.x);
+                PopItemFlag();
             }
             EndPopup();
         }
@@ -6333,6 +6335,7 @@ bool ImGui::ColorPicker4(const char* label, float col[4], ImGuiColorEditFlags fl
     if (!(flags & ImGuiColorEditFlags_NoSidePreview))
     {
         PushItemFlag(ImGuiItemFlags_NoNavDefaultFocus, true);
+        PushItemFlag(ImGuiItemFlags_MixedValue, false);
         ImVec4 col_v4(col[0], col[1], col[2], (flags & ImGuiColorEditFlags_NoAlpha) ? 1.0f : col[3]);
         if ((flags & ImGuiColorEditFlags_NoLabel))
             Text("Current");
@@ -6350,6 +6353,7 @@ bool ImGui::ColorPicker4(const char* label, float col[4], ImGuiColorEditFlags fl
             }
         }
         PopItemFlag();
+        PopItemFlag();
         EndGroup();
     }
 
@@ -6568,14 +6572,20 @@ bool ImGui::ColorButton(const char* desc_id, const ImVec4& col, ImGuiColorEditFl
     if (flags & ImGuiColorEditFlags_InputHSV)
         ColorConvertHSVtoRGB(col_rgb.x, col_rgb.y, col_rgb.z, col_rgb.x, col_rgb.y, col_rgb.z);
 
-    ImVec4 col_rgb_without_alpha(col_rgb.x, col_rgb.y, col_rgb.z, 1.0f);
+    const ImVec4 col_rgb_without_alpha(col_rgb.x, col_rgb.y, col_rgb.z, 1.0f);
-    float grid_step = ImMin(size.x, size.y) / 2.99f;
+    const float grid_step = ImMin(size.x, size.y) / 2.99f;
-    float rounding = ImMin(g.Style.FrameRounding, grid_step * 0.5f);
+    const float rounding = ImMin(g.Style.FrameRounding, grid_step * 0.5f);
+    const bool is_mixed = (g.LastItemData.ItemFlags & ImGuiItemFlags_MixedValue) != 0;
 
     const float backup_alpha = g.Style.Alpha;
     if (g.DisabledStackSize > 0)
         g.Style.Alpha = g.DisabledAlphaBackup; // Cancel out effect of BeginDisabled() for color swatches.
-    if ((flags & ImGuiColorEditFlags_AlphaPreviewHalf) && col_rgb.w < 1.0f)
+    if (is_mixed)
+    {
+        window->DrawList->AddRectFilled(bb.Min, bb.Max, GetColorU32(ImGuiCol_FrameBg), rounding);
+        RenderTextClipped(ImVec2(bb.Min.x, bb.Min.y + g.Style.FramePadding.y), bb.Max, g.MixedValueLabel, NULL, NULL, ImVec2(0.5f, 0.0f));
+    }
+    else if ((flags & ImGuiColorEditFlags_AlphaPreviewHalf) && col_rgb.w < 1.0f)
     {
         float mid_x = IM_ROUND((bb.Min.x + bb.Max.x) * 0.5f);
         if ((flags & ImGuiColorEditFlags_AlphaNoBg) == 0)
@@ -6612,7 +6622,9 @@ bool ImGui::ColorButton(const char* desc_id, const ImVec4& col, ImGuiColorEditFl
             SetDragDropPayload(IMGUI_PAYLOAD_TYPE_COLOR_3F, &col_rgb, sizeof(float) * 3, ImGuiCond_Once);
         else
             SetDragDropPayload(IMGUI_PAYLOAD_TYPE_COLOR_4F, &col_rgb, sizeof(float) * 4, ImGuiCond_Once);
+        PushItemFlag(ImGuiItemFlags_MixedValue, false);
         ColorButton(desc_id, col, flags);
+        PopItemFlag();
         SameLine();
         TextEx("Color");
         EndDragDropSource();
@@ -6656,7 +6668,9 @@ void ImGui::ColorTooltip(const char* text, const float* col, ImGuiColorEditFlags
     ImVec4 cf(col[0], col[1], col[2], (flags & ImGuiColorEditFlags_NoAlpha) ? 1.0f : col[3]);
     int cr = IM_F32_TO_INT8_SAT(col[0]), cg = IM_F32_TO_INT8_SAT(col[1]), cb = IM_F32_TO_INT8_SAT(col[2]), ca = (flags & ImGuiColorEditFlags_NoAlpha) ? 255 : IM_F32_TO_INT8_SAT(col[3]);
     ImGuiColorEditFlags flags_to_forward = ImGuiColorEditFlags_InputMask_ | ImGuiColorEditFlags_AlphaMask_;
+    PushItemFlag(ImGuiItemFlags_MixedValue, false);
     ColorButton("##preview", cf, (flags & flags_to_forward) | ImGuiColorEditFlags_NoTooltip, sz);
+    PopItemFlag();
     SameLine();
     if ((flags & ImGuiColorEditFlags_InputRGB) || !(flags & ImGuiColorEditFlags_InputMask_))
     {