Add a flag to ImTextureID that disables alpha test

src/xenia/ui/gl/gl_immediate_drawer.cc

@@ -270,6 +270,16 @@ void GLImmediateDrawer::End() {
   }
 }
 
+void GLImmediateDrawer::EnableAlphaTest(bool enable) {
+  if (enable) {
+    glEnablei(GL_BLEND, 0);
+    glBlendEquationi(0, GL_FUNC_ADD);
+    glBlendFunci(0, GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+  } else {
+    glDisablei(GL_BLEND, 0);
+  }
+}
+
 }  // namespace gl
 }  // namespace ui
 }  // namespace xe

src/xenia/ui/gl/gl_immediate_drawer.h

@@ -37,6 +37,8 @@ class GLImmediateDrawer : public ImmediateDrawer {
   void EndDrawBatch() override;
   void End() override;
 
+  void EnableAlphaTest(bool enable);
+
  private:
   void InitializeShaders();
 

src/xenia/ui/imgui_drawer.cc

@@ -203,11 +203,16 @@ void ImGuiDrawer::RenderDrawLists(ImDrawData* data) {
     for (int j = 0; j < cmd_list->CmdBuffer.size(); ++j) {
       const auto& cmd = cmd_list->CmdBuffer[j];
 
+      if (reinterpret_cast<uintptr_t>(cmd.TextureId) & kIgnoreAlpha) {
+        drawer->EnableAlphaTest(false);
+      }
+
       ImmediateDraw draw;
       draw.primitive_type = ImmediatePrimitiveType::kTriangles;
       draw.count = cmd.ElemCount;
       draw.index_offset = index_offset;
-      draw.texture_handle = reinterpret_cast<uintptr_t>(cmd.TextureId);
+      draw.texture_handle =
+          reinterpret_cast<uintptr_t>(cmd.TextureId) & 0xFFFFFFFF;
       draw.scissor = true;
       draw.scissor_rect[0] = static_cast<int>(cmd.ClipRect.x);
       draw.scissor_rect[1] = static_cast<int>(height - cmd.ClipRect.w);
@@ -215,6 +220,10 @@ void ImGuiDrawer::RenderDrawLists(ImDrawData* data) {
       draw.scissor_rect[3] = static_cast<int>(cmd.ClipRect.w - cmd.ClipRect.y);
       drawer->Draw(draw);
 
+      if (reinterpret_cast<uintptr_t>(cmd.TextureId) & kIgnoreAlpha) {
+        drawer->EnableAlphaTest(true);
+      }
+
       index_offset += cmd.ElemCount;
     }
 

src/xenia/ui/imgui_drawer.h

@@ -35,6 +35,8 @@ class ImGuiDrawer : public WindowListener {
 
   ImGuiIO& GetIO();
 
+  static const uint64_t kIgnoreAlpha = (1ull << 32);
+
  protected:
   void Initialize();
   void SetupFont();

src/xenia/ui/immediate_drawer.h

@@ -113,6 +113,8 @@ class ImmediateDrawer {
   // Ends drawing in immediate mode and flushes contents.
   virtual void End() = 0;
 
+  virtual void EnableAlphaTest(bool enable) = 0;
+
  protected:
   ImmediateDrawer(GraphicsContext* graphics_context)
       : graphics_context_(graphics_context) {}