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();