Method ColorEdit4

src/imgui/imgui_widgets.cpp:5688–5934

Edit colors components (each component in 0.0f..1.0f range). See enum ImGuiColorEditFlags_ for available options. e.g. Only access 3 floats if ImGuiColorEditFlags_NoAlpha flag is set. With typical options: Left-click on color square to open color picker. Right-click to open option menu. CTRL+Click over input fields to edit them and TAB to go to next item.

// See enum ImGuiColorEditFlags_ for available options. e.g. Only access 3 floats if ImGuiColorEditFlags_NoAlpha flag is set.
// With typical options: Left-click on color square to open color picker. Right-click to open option menu. CTRL+Click over input fields to edit them and TAB to go to next item.
bool ImGui::ColorEdit4(const char* label, float col[4], ImGuiColorEditFlags flags)
{
    ImGuiWindow* window = GetCurrentWindow();
    if (window->SkipItems)
        return false;

    ImGuiContext& g = *GImGui;
    const ImGuiStyle& style = g.Style;
    const float square_sz = GetFrameHeight();
    const char* label_display_end = FindRenderedTextEnd(label);
    float w_full = CalcItemWidth();
    g.NextItemData.ClearFlags();

    BeginGroup();
    PushID(label);
    const bool set_current_color_edit_id = (g.ColorEditCurrentID == 0);
    if (set_current_color_edit_id)
        g.ColorEditCurrentID = window->IDStack.back();

    // If we're not showing any slider there's no point in doing any HSV conversions
    const ImGuiColorEditFlags flags_untouched = flags;
    if (flags & ImGuiColorEditFlags_NoInputs)
        flags = (flags & (~ImGuiColorEditFlags_DisplayMask_)) | ImGuiColorEditFlags_DisplayRGB | ImGuiColorEditFlags_NoOptions;

    // Context menu: display and modify options (before defaults are applied)
    if (!(flags & ImGuiColorEditFlags_NoOptions))
        ColorEditOptionsPopup(col, flags);

    // Read stored options
    if (!(flags & ImGuiColorEditFlags_DisplayMask_))
        flags |= (g.ColorEditOptions & ImGuiColorEditFlags_DisplayMask_);
    if (!(flags & ImGuiColorEditFlags_DataTypeMask_))
        flags |= (g.ColorEditOptions & ImGuiColorEditFlags_DataTypeMask_);
    if (!(flags & ImGuiColorEditFlags_PickerMask_))
        flags |= (g.ColorEditOptions & ImGuiColorEditFlags_PickerMask_);
    if (!(flags & ImGuiColorEditFlags_InputMask_))
        flags |= (g.ColorEditOptions & ImGuiColorEditFlags_InputMask_);
    flags |= (g.ColorEditOptions & ~(ImGuiColorEditFlags_DisplayMask_ | ImGuiColorEditFlags_DataTypeMask_ | ImGuiColorEditFlags_PickerMask_ | ImGuiColorEditFlags_InputMask_));
    IM_ASSERT(ImIsPowerOfTwo(flags & ImGuiColorEditFlags_DisplayMask_)); // Check that only 1 is selected
    IM_ASSERT(ImIsPowerOfTwo(flags & ImGuiColorEditFlags_InputMask_));   // Check that only 1 is selected

    const bool alpha = (flags & ImGuiColorEditFlags_NoAlpha) == 0;
    const bool hdr = (flags & ImGuiColorEditFlags_HDR) != 0;
    const int components = alpha ? 4 : 3;
    const float w_button = (flags & ImGuiColorEditFlags_NoSmallPreview) ? 0.0f : (square_sz + style.ItemInnerSpacing.x);
    const float w_inputs = ImMax(w_full - w_button, 1.0f);
    w_full = w_inputs + w_button;

    // Convert to the formats we need
    float f[4] = { col[0], col[1], col[2], alpha ? col[3] : 1.0f };
    if ((flags & ImGuiColorEditFlags_InputHSV) && (flags & ImGuiColorEditFlags_DisplayRGB))
        ColorConvertHSVtoRGB(f[0], f[1], f[2], f[0], f[1], f[2]);
    else if ((flags & ImGuiColorEditFlags_InputRGB) && (flags & ImGuiColorEditFlags_DisplayHSV))
    {
        // Hue is lost when converting from grayscale rgb (saturation=0). Restore it.
        ColorConvertRGBtoHSV(f[0], f[1], f[2], f[0], f[1], f[2]);
        ColorEditRestoreHS(col, &f[0], &f[1], &f[2]);
    }