Fix T63936 GPUSelect: Read depth in the end

fix T63936 introduced  in 86914e7133.

Reviewers: fclem

Reviewed By: fclem

Tags: #bf_blender

Maniphest Tasks: T63936

Differential Revision: https://developer.blender.org/D4750

source/blender/gpu/intern/gpu_select.c

@@ -120,7 +120,7 @@ bool GPU_select_load_id(uint id)
     }
     default: /* ALGO_GL_PICK */
     {
-      return gpu_select_pick_load_id(id);
+      return gpu_select_pick_load_id(id, false);
     }
   }
 }

source/blender/gpu/intern/gpu_select_pick.c

@@ -476,12 +476,12 @@ static void gpu_select_load_id_pass_nearest(const DepthBufCache *rect_prev,
   }
 }
 
-bool gpu_select_pick_load_id(uint id)
+bool gpu_select_pick_load_id(uint id, bool end)
 {
   GPUPickState *ps = &g_pick_state;
 
   if (ps->gl.is_init) {
-    if (id == ps->gl.prev_id) {
+    if (id == ps->gl.prev_id && !end) {
       /* No need to read if we are still drawing for the same id since
        * all these depths will be merged / deduplicated in the end. */
       return true;
@@ -543,7 +543,7 @@ uint gpu_select_pick_end(void)
   if (ps->is_cached == false) {
     if (ps->gl.is_init) {
       /* force finishing last pass */
-      gpu_select_pick_load_id(ps->gl.prev_id);
+      gpu_select_pick_load_id(ps->gl.prev_id, true);
     }
     gpuPopAttr();
     glColorMask(GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE);

source/blender/gpu/intern/gpu_select_private.h

@@ -28,7 +28,7 @@
 
 /* gpu_select_pick */
 void gpu_select_pick_begin(uint (*buffer)[4], uint bufsize, const rcti *input, char mode);
-bool gpu_select_pick_load_id(uint id);
+bool gpu_select_pick_load_id(uint id, bool end);
 uint gpu_select_pick_end(void);
 
 void gpu_select_pick_cache_begin(void);