From 9e7a576ceed473dea031262f9d19489b9e841cbf Mon Sep 17 00:00:00 2001
From: Miguel Pozo <pragma37@gmail.com>
Date: Fri, 13 Oct 2023 19:18:46 +0200
Subject: [PATCH] Workbench: Fix: depth_in_front not being copied after the
 first sample

---
 .../workbench/workbench_effect_antialiasing.cc     | 14 +++++++++-----
 .../draw/engines/workbench/workbench_engine.cc     |  4 ++--
 .../draw/engines/workbench/workbench_private.hh    | 12 ++++++++----
 3 files changed, 19 insertions(+), 11 deletions(-)

diff --git a/source/blender/draw/engines/workbench/workbench_effect_antialiasing.cc b/source/blender/draw/engines/workbench/workbench_effect_antialiasing.cc
index f21e2cbd3cc..c8e01c58261 100644
--- a/source/blender/draw/engines/workbench/workbench_effect_antialiasing.cc
+++ b/source/blender/draw/engines/workbench/workbench_effect_antialiasing.cc
@@ -166,8 +166,6 @@ void AntiAliasingPass::sync(const SceneState &scene_state, SceneResources &resou
   sample0_depth_tx_.ensure_2d(GPU_DEPTH24_STENCIL8,
                               scene_state.resolution,
                               GPU_TEXTURE_USAGE_SHADER_READ | GPU_TEXTURE_USAGE_ATTACHMENT);
-  sample0_depth_in_front_tx_.ensure_2d(
-      GPU_DEPTH24_STENCIL8, scene_state.resolution, GPU_TEXTURE_USAGE_ATTACHMENT);
 
   taa_accumulation_ps_.init();
   taa_accumulation_ps_.state_set(scene_state.sample == 0 ?
@@ -257,7 +255,8 @@ void AntiAliasingPass::setup_view(View &view, const SceneState &scene_state)
 void AntiAliasingPass::draw(Manager &manager,
                             View &view,
                             const SceneState &scene_state,
-                            SceneResources &resources)
+                            SceneResources &resources,
+                            GPUTexture *depth_in_front_tx)
 {
   if (resources.depth_in_front_tx.is_valid() && scene_state.sample == 0 &&
       scene_state.overlays_enabled)
@@ -278,14 +277,19 @@ void AntiAliasingPass::draw(Manager &manager,
     if (scene_state.sample == 0) {
       GPU_texture_copy(sample0_depth_tx_, resources.depth_tx);
       if (resources.depth_in_front_tx.is_valid()) {
+        sample0_depth_in_front_tx_.ensure_2d(
+            GPU_DEPTH24_STENCIL8, scene_state.resolution, GPU_TEXTURE_USAGE_ATTACHMENT);
         GPU_texture_copy(sample0_depth_in_front_tx_, resources.depth_in_front_tx);
       }
+      else {
+        sample0_depth_in_front_tx_.free();
+      }
     }
     else if (!DRW_state_is_scene_render() || last_sample) {
       /* Copy back the saved depth buffer for correct overlays. */
       GPU_texture_copy(resources.depth_tx, sample0_depth_tx_);
-      if (resources.depth_in_front_tx.is_valid()) {
-        GPU_texture_copy(resources.depth_in_front_tx, sample0_depth_in_front_tx_);
+      if (sample0_depth_in_front_tx_.is_valid()) {
+        GPU_texture_copy(depth_in_front_tx, sample0_depth_in_front_tx_);
       }
     }
   }
diff --git a/source/blender/draw/engines/workbench/workbench_engine.cc b/source/blender/draw/engines/workbench/workbench_engine.cc
index 416941269c0..667a381d2f5 100644
--- a/source/blender/draw/engines/workbench/workbench_engine.cc
+++ b/source/blender/draw/engines/workbench/workbench_engine.cc
@@ -446,7 +446,7 @@ class Instance {
 
     if (scene_state.render_finished) {
       /* Just copy back the already rendered result */
-      anti_aliasing_ps.draw(manager, view, scene_state, resources);
+      anti_aliasing_ps.draw(manager, view, scene_state, resources, depth_in_front_tx);
       return;
     }
 
@@ -476,7 +476,7 @@ class Instance {
     volume_ps.draw(manager, view, resources);
     outline_ps.draw(manager, resources);
     dof_ps.draw(manager, view, resources, resolution);
-    anti_aliasing_ps.draw(manager, view, scene_state, resources);
+    anti_aliasing_ps.draw(manager, view, scene_state, resources, depth_in_front_tx);
 
     resources.object_id_tx.release();
   }
diff --git a/source/blender/draw/engines/workbench/workbench_private.hh b/source/blender/draw/engines/workbench/workbench_private.hh
index eead3b2049b..eadaac8d85f 100644
--- a/source/blender/draw/engines/workbench/workbench_private.hh
+++ b/source/blender/draw/engines/workbench/workbench_private.hh
@@ -563,10 +563,14 @@ class AntiAliasingPass {
   void init(const SceneState &scene_state);
   void sync(const SceneState &scene_state, SceneResources &resources);
   void setup_view(View &view, const SceneState &scene_state);
-  void draw(Manager &manager,
-            View &view,
-            const SceneState &scene_state,
-            SceneResources &resources);
+  void draw(
+      Manager &manager,
+      View &view,
+      const SceneState &scene_state,
+      SceneResources &resources,
+      /** Passed directly since we may need to copy back the results from the first sample,
+       * and resources.depth_in_front_tx is only valid when mesh passes have to draw to it. */
+      GPUTexture *depth_in_front_tx);
 };
 
 }  // namespace blender::workbench