source/blender/render/hydra/render_task_delegate.cc

@@ -121,6 +121,18 @@ void RenderTaskDelegate::read_aov(pxr::TfToken const &aov_key, void *data)
   buffer->Unmap();
 }
 
+void RenderTaskDelegate::read_aov(pxr::TfToken const &aov_key, GPUTexture *texture)
+{
+  pxr::HdRenderBuffer *buffer = (pxr::HdRenderBuffer *)GetRenderIndex().GetBprim(
+      pxr::HdPrimTypeTokens->renderBuffer, buffer_id(aov_key));
+  if (!buffer) {
+    return;
+  }
+  void *buf_data = buffer->Map();
+  GPU_texture_update(texture, GPU_DATA_FLOAT, buf_data);
+  buffer->Unmap();
+}
+
 void RenderTaskDelegate::bind() {}
 
 void RenderTaskDelegate::unbind() {}
@@ -202,6 +214,27 @@ void GPURenderTaskDelegate::read_aov(pxr::TfToken const &aov_key, void *data)
   MEM_freeN(tex_data);
 }
 
+void GPURenderTaskDelegate::read_aov(pxr::TfToken const &aov_key, GPUTexture *texture)
+{
+  GPUTexture *tex = nullptr;
+  int c;
+  if (aov_key == pxr::HdAovTokens->color) {
+    tex = tex_color_;
+    c = 4;
+  }
+  else if (aov_key == pxr::HdAovTokens->depth) {
+    tex = tex_depth_;
+    c = 1;
+  }
+  if (!tex) {
+    return;
+  }
+
+  void *tex_data = GPU_texture_read(tex, GPU_DATA_FLOAT, 0);
+  GPU_texture_update(texture, GPU_DATA_FLOAT, tex_data);
+  MEM_freeN(tex_data);
+}
+
 void GPURenderTaskDelegate::bind()
 {
   if (!framebuffer_) {

source/blender/render/hydra/render_task_delegate.h

@@ -27,6 +27,7 @@ class RenderTaskDelegate : public pxr::HdSceneDelegate {
   virtual void set_viewport(pxr::GfVec4d const &viewport);
   virtual void add_aov(pxr::TfToken const &aov_key);
   virtual void read_aov(pxr::TfToken const &aov_key, void *data);
+  virtual void read_aov(pxr::TfToken const &aov_key, GPUTexture *texture);
   virtual void bind();
   virtual void unbind();
 
@@ -46,6 +47,7 @@ class GPURenderTaskDelegate : public RenderTaskDelegate {
   void set_viewport(pxr::GfVec4d const &viewport) override;
   void add_aov(pxr::TfToken const &aov_key) override;
   void read_aov(pxr::TfToken const &aov_key, void *data) override;
+  void read_aov(pxr::TfToken const &aov_key, GPUTexture *texture) override;
   void bind() override;
   void unbind() override;
 

source/blender/render/hydra/viewport_engine.cc

@@ -158,7 +158,9 @@ DrawTexture::~DrawTexture()
 void DrawTexture::write_data(int width, int height, const void *data)
 {
   if (texture_ && width == GPU_texture_width(texture_) && height == GPU_texture_height(texture_)) {
-    GPU_texture_update(texture_, GPU_DATA_FLOAT, data);
+    if (data) {
+      GPU_texture_update(texture_, GPU_DATA_FLOAT, data);
+    }
     return;
   }
 
@@ -196,6 +198,11 @@ void DrawTexture::draw(GPUShader *shader, GPUTexture *tex, const pxr::GfVec4d &v
   GPU_matrix_pop();
 }
 
+GPUTexture *DrawTexture::texture() const
+{
+  return texture_;
+}
+
 void ViewportEngine::render(Depsgraph * /* depsgraph */)
 {
   /* Empty function */
@@ -236,9 +243,8 @@ void ViewportEngine::render(Depsgraph * /* depsgraph */, bContext *context)
   engine_->Execute(render_index_.get(), &tasks);
 
   if ((bl_engine_->type->flag & RE_USE_GPU_CONTEXT) == 0) {
-    std::vector<float> data(view_settings.width() * view_settings.height() * 4, 0.0f);
+    draw_texture_.write_data(view_settings.width(), view_settings.height(), nullptr);
-    render_task_delegate_->read_aov(pxr::HdAovTokens->color, data.data());
+    render_task_delegate_->read_aov(pxr::HdAovTokens->color, draw_texture_.texture());
-    draw_texture_.write_data(view_settings.width(), view_settings.height(), data.data());
     draw_texture_.draw(shader, viewport);
   }
 

source/blender/render/hydra/viewport_engine.h

@@ -21,6 +21,7 @@ class DrawTexture {
   void write_data(int width, int height, const void *data);
   void draw(GPUShader *shader, const pxr::GfVec4d &viewport);
   void draw(GPUShader *shader, GPUTexture *tex, const pxr::GfVec4d &viewport);
+  GPUTexture *texture() const;
 
  private:
   GPUTexture *texture_ = nullptr;