Added ImGuiColorEditFlagsFlags_InputHSV. (#2383, #2384)

docs/CHANGELOG.txt

@@ -62,6 +62,9 @@ Other Changes:
 - InputText: Fixed various display corruption related to swapping the underlying buffer while
   a input widget is active (both for writable and read-only paths). Often they would manifest
   when manipulating the scrollbar of a multi-line input text.
+- ColorEdit, ColorPicker, ColorButton: Added ImGuiColorEditFlags_InputHSV to manipulate color
+  values encoded as HSV (in order to avoid HSV<>RGB round trips and associated singularities).
+  (#2383, #2384) [@haldean]
 - ColorPicker: Fixed a bug/assertion when displaying a color picker in a collapsed window
   while dragging its title bar. (#2389)
 - ColorEdit: Fixed tooltip not honoring the ImGuiColorEditFlags_NoAlpha contract of never

imgui.h

@@ -1117,8 +1117,7 @@ enum ImGuiColorEditFlags_
     ImGuiColorEditFlags_NoSidePreview   = 1 << 8,   //              // ColorPicker: disable bigger color preview on right side of the picker, use small colored square preview instead.
     ImGuiColorEditFlags_NoDragDrop      = 1 << 9,   //              // ColorEdit: disable drag and drop target. ColorButton: disable drag and drop source.
 
-    // User Options (right-click on widget to change some of them). You can set application defaults using SetColorEditOptions(). 
-    // The intent is that you probably don't want to override them in most of your calls, let the user choose via the option menu and/or call SetColorEditOptions() during startup.
+    // User Options (right-click on widget to change some of them). 
     ImGuiColorEditFlags_AlphaBar        = 1 << 16,  //              // ColorEdit, ColorPicker: show vertical alpha bar/gradient in picker.
     ImGuiColorEditFlags_AlphaPreview    = 1 << 17,  //              // ColorEdit, ColorPicker, ColorButton: display preview as a transparent color over a checkerboard, instead of opaque.
     ImGuiColorEditFlags_AlphaPreviewHalf= 1 << 18,  //              // ColorEdit, ColorPicker, ColorButton: display half opaque / half checkerboard, instead of opaque.
@@ -1128,14 +1127,20 @@ enum ImGuiColorEditFlags_
     ImGuiColorEditFlags_DisplayHex      = 1 << 22,  // [Display]    // "
     ImGuiColorEditFlags_Uint8           = 1 << 23,  // [DataType]   // ColorEdit, ColorPicker, ColorButton: _display_ values formatted as 0..255.
     ImGuiColorEditFlags_Float           = 1 << 24,  // [DataType]   // ColorEdit, ColorPicker, ColorButton: _display_ values formatted as 0.0f..1.0f floats instead of 0..255 integers. No round-trip of value via integers.
-    ImGuiColorEditFlags_PickerHueBar    = 1 << 25,  // [PickerMode] // ColorPicker: bar for Hue, rectangle for Sat/Value.
-    ImGuiColorEditFlags_PickerHueWheel  = 1 << 26,  // [PickerMode] // ColorPicker: wheel for Hue, triangle for Sat/Value.
+    ImGuiColorEditFlags_PickerHueBar    = 1 << 25,  // [Picker]     // ColorPicker: bar for Hue, rectangle for Sat/Value.
+    ImGuiColorEditFlags_PickerHueWheel  = 1 << 26,  // [Picker]     // ColorPicker: wheel for Hue, triangle for Sat/Value.
+    ImGuiColorEditFlags_InputRGB        = 1 << 27,  // [Input]      // ColorEdit, ColorPicker: input and output data in RGB format.
+    ImGuiColorEditFlags_InputHSV        = 1 << 28,  // [Input]      // ColorEdit, ColorPicker: input and output data in HSV format.
+
+    // Defaults Options. You can set application defaults using SetColorEditOptions(). The intent is that you probably don't want to
+    // override them in most of your calls. Let the user choose via the option menu and/or call SetColorEditOptions() once during startup.
+    ImGuiColorEditFlags__OptionsDefault = ImGuiColorEditFlags_Uint8|ImGuiColorEditFlags_DisplayRGB|ImGuiColorEditFlags_InputRGB|ImGuiColorEditFlags_PickerHueBar,
 
     // [Internal] Masks
     ImGuiColorEditFlags__DisplayMask    = ImGuiColorEditFlags_DisplayRGB|ImGuiColorEditFlags_DisplayHSV|ImGuiColorEditFlags_DisplayHex,
     ImGuiColorEditFlags__DataTypeMask   = ImGuiColorEditFlags_Uint8|ImGuiColorEditFlags_Float,
     ImGuiColorEditFlags__PickerMask     = ImGuiColorEditFlags_PickerHueWheel|ImGuiColorEditFlags_PickerHueBar,
-    ImGuiColorEditFlags__OptionsDefault = ImGuiColorEditFlags_Uint8|ImGuiColorEditFlags_DisplayRGB|ImGuiColorEditFlags_PickerHueBar    // Change application default using SetColorEditOptions()
+    ImGuiColorEditFlags__InputMask      = ImGuiColorEditFlags_InputRGB|ImGuiColorEditFlags_InputHSV
 
     // Obsolete names (will be removed)
 #ifndef IMGUI_DISABLE_OBSOLETE_FUNCTIONS

imgui_demo.cpp

@@ -1171,6 +1171,16 @@ static void ShowDemoWindowWidgets()
         if (ImGui::Button("Default: Float + HDR + Hue Wheel"))
             ImGui::SetColorEditOptions(ImGuiColorEditFlags_Float | ImGuiColorEditFlags_HDR | ImGuiColorEditFlags_PickerHueWheel);
 
+        // HSV encoded support (to avoid RGB<>HSV round trips and singularities when S==0 or V==0)
+        static ImVec4 color_stored_as_hsv(0.23f, 1.0f, 1.0f, 1.0f);
+        ImGui::Spacing();
+        ImGui::Text("HSV encoded colors");
+        ImGui::SameLine(); HelpMarker("By default, colors are given to ColorEdit and ColorPicker in RGB, but ImGuiColorEditFlags_InputHSV allows you to store colors as HSV and pass them to ColorEdit and ColorPicker as HSV. This comes with the added benefit that you can manipulate hue values with the picker even when saturation or value are zero.");
+        ImGui::Text("Color widget with InputHSV:");
+        ImGui::ColorEdit4("HSV shown as HSV##1", (float*)&color_stored_as_hsv, ImGuiColorEditFlags_DisplayRGB | ImGuiColorEditFlags_InputHSV | ImGuiColorEditFlags_Float);
+        ImGui::ColorEdit4("HSV shown as RGB##1", (float*)&color_stored_as_hsv, ImGuiColorEditFlags_DisplayHSV | ImGuiColorEditFlags_InputHSV | ImGuiColorEditFlags_Float);
+        ImGui::DragFloat4("Raw HSV values", (float*)&color_stored_as_hsv, 0.01f, 0.0f, 1.0f);
+
         ImGui::TreePop();
     }