What renders over what

engines/render_gl/h3r_renderengine.cpp

@@ -58,9 +58,7 @@ static bool global_render_gl_init {false};
 RenderEngine::RenderEngine() : RenderEngine {H3R_MAX_SPRITE_NUM} {}
 RenderEngine::RenderEngine(GLsizeiptr max_sprite_frames)
 {
-    //TODO then figure out little z-offsets (relative) for each control
-    //     (f(z-order) so the entire UI shall be rendered in one gl call
-    //     GL_DEPTH_TEST; and compare to the above; choose the less-code one
+    //LATER RenderEngine::UI ().ChangeZOrder ()
 
     H3R_ENSURE(global_render_gl_init, "You forgot to call RenderEngine::Init()")
 

engines/render_gl/h3r_renderengine.h

@@ -74,9 +74,12 @@ using H3Rfloat = GLfloat;
 // project shall be able to use some of the best renderers out there - I know
 // you want to play multi-dimensional "Heroes III"; patience.
 //
-// Right now the z-order equals the order of UploadFrame() it seems; although
-// I'm not sure how Open GL orders things, with equal z coordinates, inside VBO.
-//TODO R&D the topic.
+// Right now the z-order equals the order of UploadFrame(), because that's what
+// glMultiDrawArrays passes to the pipeline.
+// The z-order, if it becomes a requirement, shall be implemented via a z
+// coordinate: {x,y,u,v} shall become {x,y,z,u,v}; with the ability to modify
+// said z coordinate per key. The map window: the map control shall be defined
+// 1st by the map window, so it will be rendered prior everything else.
 class RenderEngine final
 {
     // Bind texture id to glMultiDrawArrays. Because frame0 could be at

project

@@ -79,8 +79,8 @@ should they've just published the original source code.
 A few things:
  * UI - there are a few forms and dialogs - nothing to re-discover because most
         of them are pre-rendered pictures that just need hit rectangles
- * rendering - z-order, shadow and opacity maps, sprite atlases - nothing new
-               here; alpha blending is nowhere to be found yet
+ * done: rendering - z-order, shadow and opacity maps, sprite atlases - nothing
+         new here; alpha blending was "found" :) (at fonts)
  * game: a 3D table of quad patches: n*n*l, where n=18,36,72,144 and l=1,2
     - quad: layered: terrain, river, road, objects, visibility (per kingdom);
       also, the game does some kind of patch blending:

ui/h3r_control.h

@@ -66,8 +66,8 @@ class Control
     private: Box _bb; // bounding box
     private: bool _enabled {true}; // whether the user can interact with it
 
-    private: List<Control *> _z;   // z-order; render: from 0 to count-1
-    private: List<Control *> _n;   //LATER non-visible ones; if any
+    //LATER RenderEngine::UI ().ChangeZOrder ()
+    private: List<Control *> _n;   // Sub-controls; could be useless
     private: void Add(Control *);
 
     public: Control(Control * = nullptr);