Updated ImGui.

3rdparty/dear-imgui/imgui.cpp

@@ -622,6 +622,7 @@ CODE
 
  Q: How can I display an image? What is ImTextureID, how does it works?
  A: Short explanation:
+    - Please read Wiki entry for examples: https://github.com/ocornut/imgui/wiki/Image-Loading-and-Displaying-Examples
     - You may use functions such as ImGui::Image(), ImGui::ImageButton() or lower-level ImDrawList::AddImage() to emit draw calls that will use your own textures.
     - Actual textures are identified in a way that is up to the user/engine. Those identifiers are stored and passed as ImTextureID (void*) value.
     - Loading image files from the disk and turning them into a texture is not within the scope of Dear ImGui (for a good reason).
@@ -669,26 +670,9 @@ CODE
     This is by design and is actually a good thing, because it means your code has full control over your data types and how you display them.
     If you want to display an image file (e.g. PNG file) into the screen, please refer to documentation and tutorials for the graphics API you are using.
 
-    Here's a simplified OpenGL example using stb_image.h:
-
-        // Use stb_image.h to load a PNG from disk and turn it into raw RGBA pixel data:
-        #define STB_IMAGE_IMPLEMENTATION
-        #include <stb_image.h>
-        [...]
-        int my_image_width, my_image_height;
-        unsigned char* my_image_data = stbi_load("my_image.png", &my_image_width, &my_image_height, NULL, 4);
-
-        // Turn the RGBA pixel data into an OpenGL texture:
-        GLuint my_opengl_texture;
-        glGenTextures(1, &my_opengl_texture);
-        glBindTexture(GL_TEXTURE_2D, my_opengl_texture);
-        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
-        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
-        glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
-        glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, image_width, image_height, 0, GL_RGBA, GL_UNSIGNED_BYTE, image_data);
-
-        // Now that we have an OpenGL texture, assuming our imgui rendering function (imgui_impl_xxx.cpp file) takes GLuint as ImTextureID, we can display it:
-        ImGui::Image((void*)(intptr_t)my_opengl_texture, ImVec2(my_image_width, my_image_height));
+    Refer to the Wiki to find simplified examples for loading textures with OpenGL, DirectX9 and DirectX11:
+
+        https://github.com/ocornut/imgui/wiki/Image-Loading-and-Displaying-Examples
 
     C/C++ tip: a void* is pointer-sized storage. You may safely store any pointer or integer into it by casting your value to ImTextureID / void*, and vice-versa.
     Because both end-points (user code and rendering function) are under your control, you know exactly what is stored inside the ImTextureID / void*.

3rdparty/dear-imgui/imgui_internal.h

@@ -1012,6 +1012,8 @@ struct ImGuiContext
     ImFont                  InputTextPasswordFont;
     ImGuiID                 TempInputTextId;                    // Temporary text input when CTRL+clicking on a slider, etc.
     ImGuiColorEditFlags     ColorEditOptions;                   // Store user options for color edit widgets
+    float                   ColorEditLastHue;
+    float                   ColorEditLastColor[3];
     ImVec4                  ColorPickerRef;
     bool                    DragCurrentAccumDirty;
     float                   DragCurrentAccum;                   // Accumulator for dragging modification. Always high-precision, not rounded by end-user precision settings
@@ -1156,6 +1158,8 @@ struct ImGuiContext
         LastValidMousePos = ImVec2(0.0f, 0.0f);
         TempInputTextId = 0;
         ColorEditOptions = ImGuiColorEditFlags__OptionsDefault;
+        ColorEditLastHue = 0.0f;
+        ColorEditLastColor[0] = ColorEditLastColor[1] = ColorEditLastColor[2] = FLT_MAX;
         DragCurrentAccumDirty = false;
         DragCurrentAccum = 0.0f;
         DragSpeedDefaultRatio = 1.0f / 100.0f;

3rdparty/dear-imgui/imgui_widgets.cpp

@@ -4215,7 +4215,12 @@ bool ImGui::ColorEdit4(const char* label, float col[4], ImGuiColorEditFlags flag
     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 greyscale rgb (saturation=0). Restore it.
         ColorConvertRGBtoHSV(f[0], f[1], f[2], f[0], f[1], f[2]);
+        if (f[1] == 0 && memcmp(g.ColorEditLastColor, col, sizeof(float) * 3) == 0)
+            f[0] = g.ColorEditLastHue;
+    }
     int i[4] = { IM_F32_TO_INT8_UNBOUND(f[0]), IM_F32_TO_INT8_UNBOUND(f[1]), IM_F32_TO_INT8_UNBOUND(f[2]), IM_F32_TO_INT8_UNBOUND(f[3]) };
 
     bool value_changed = false;
@@ -4342,7 +4347,11 @@ bool ImGui::ColorEdit4(const char* label, float col[4], ImGuiColorEditFlags flag
             for (int n = 0; n < 4; n++)
                 f[n] = i[n] / 255.0f;
         if ((flags & ImGuiColorEditFlags_DisplayHSV) && (flags & ImGuiColorEditFlags_InputRGB))
+        {
+            g.ColorEditLastHue = f[0];
             ColorConvertHSVtoRGB(f[0], f[1], f[2], f[0], f[1], f[2]);
+            memcpy(g.ColorEditLastColor, f, sizeof(float) * 3);
+        }
         if ((flags & ImGuiColorEditFlags_DisplayRGB) && (flags & ImGuiColorEditFlags_InputHSV))
             ColorConvertRGBtoHSV(f[0], f[1], f[2], f[0], f[1], f[2]);
 
@@ -4519,9 +4528,16 @@ bool ImGui::ColorPicker4(const char* label, float col[4], ImGuiColorEditFlags fl
     float H = col[0], S = col[1], V = col[2];
     float R = col[0], G = col[1], B = col[2];
     if (flags & ImGuiColorEditFlags_InputRGB)
+    {
+        // Hue is lost when converting from greyscale rgb (saturation=0). Restore it.
         ColorConvertRGBtoHSV(R, G, B, H, S, V);
+        if (S == 0 && memcmp(g.ColorEditLastColor, col, sizeof(float) * 3) == 0)
+            H = g.ColorEditLastHue;
+    }
     else if (flags & ImGuiColorEditFlags_InputHSV)
+    {
         ColorConvertHSVtoRGB(H, S, V, R, G, B);
+    }
 
     bool value_changed = false, value_changed_h = false, value_changed_sv = false;
 
@@ -4643,6 +4659,8 @@ bool ImGui::ColorPicker4(const char* label, float col[4], ImGuiColorEditFlags fl
         if (flags & ImGuiColorEditFlags_InputRGB)
         {
             ColorConvertHSVtoRGB(H >= 1.0f ? H - 10 * 1e-6f : H, S > 0.0f ? S : 10*1e-6f, V > 0.0f ? V : 1e-6f, col[0], col[1], col[2]);
+            g.ColorEditLastHue = H;
+            memcpy(g.ColorEditLastColor, col, sizeof(float) * 3);
         }
         else if (flags & ImGuiColorEditFlags_InputHSV)
         {
@@ -4696,6 +4714,8 @@ bool ImGui::ColorPicker4(const char* label, float col[4], ImGuiColorEditFlags fl
             G = col[1];
             B = col[2];
             ColorConvertRGBtoHSV(R, G, B, H, S, V);
+            if (S == 0 && memcmp(g.ColorEditLastColor, col, sizeof(float) * 3) == 0) // Fix local Hue as display below will use it immediately.
+                H = g.ColorEditLastHue;
         }
         else if (flags & ImGuiColorEditFlags_InputHSV)
         {