source/blender/compositor/realtime_compositor/COM_result.hh

@@ -72,7 +72,11 @@ enum class ResultPrecision : uint8_t {
  * the results of identity operations, that is, operations that do nothing to their inputs in
  * certain configurations. In which case, the proxy result is left as is with no extra
  * transformation on its domain whatsoever. Proxy results can be created by calling the
- * pass_through method, see that method for more details. */
+ * pass_through method, see that method for more details.
+ *
+ * A result can wrap an external texture that is not allocated nor managed by the result. This is
+ * set up by a call to the wrap_external method. In that case, when the reference count eventually
+ * reach zero, the texture will not be freed. */
 class Result {
  private:
   /* The base type of the result's texture or single value. */
@@ -120,6 +124,10 @@ class Result {
    * calling the pass_through method, which sets this result to be the master of a target result.
    * See that method for more information. */
   Result *master_ = nullptr;
+  /* If true, then the result wraps an external texture that is not allocated nor managed by the
+   * result. This is set up by a call to the wrap_external method. In that case, when the reference
+   * count eventually reach zero, the texture will not be freed. */
+  bool is_external_ = false;
 
  public:
   /* Construct a result of the given type and precision with the given texture pool that will be
@@ -203,6 +211,13 @@ class Result {
    * a practical example of use. */
   void steal_data(Result &source);
 
+  /* Set up the result to wrap an external texture that is not allocated nor managed by the result.
+   * The is_external_ member will be set to true, the domain will be set to have the same size as
+   * the texture, and the texture will be set to the given texture. See the is_external_ member for
+   * more information. The given texture should have the same format as the result and is assumed
+   * to have a lifetime that covers the evaluation of the compositor. */
+  void wrap_external(GPUTexture *texture);
+
   /* Sets the transformation of the domain of the result to the given transformation. */
   void set_transformation(const float3x3 &transformation);
 

source/blender/compositor/realtime_compositor/intern/result.cc

@@ -192,6 +192,19 @@ void Result::steal_data(Result &source)
   source.texture_pool_ = nullptr;
 }
 
+void Result::wrap_external(GPUTexture *texture)
+{
+  const eGPUTextureFormat texture_format = GPU_texture_format(texture);
+  BLI_assert(texture_format == get_texture_format());
+  BLI_assert(!is_allocated());
+  BLI_assert(!master_);
+
+  texture_ = texture;
+  is_external_ = true;
+  is_single_value_ = false;
+  domain_ = Domain(int2(GPU_texture_width(texture), GPU_texture_height(texture)));
+}
+
 void Result::set_transformation(const float3x3 &transformation)
 {
   domain_.transformation = transformation;
@@ -298,7 +311,9 @@ void Result::release()
    * texture pool. */
   reference_count_--;
   if (reference_count_ == 0) {
-    texture_pool_->release(texture_);
+    if (!is_external_) {
+      texture_pool_->release(texture_);
+    }
     texture_ = nullptr;
   }
 }

source/blender/nodes/composite/nodes/node_composite_keyingscreen.cc

@@ -108,9 +108,7 @@ class KeyingScreenOperation : public NodeOperation {
     KeyingScreen &cached_keying_screen = context().cache_manager().keying_screens.get(
         context(), get_movie_clip(), movie_tracking_object, get_smoothness());
 
-    const Domain domain = compute_domain();
-    keying_screen.allocate_texture(domain);
-    GPU_texture_copy(keying_screen.texture(), cached_keying_screen.texture());
+    keying_screen.wrap_external(cached_keying_screen.texture());
   }
 
   Domain compute_domain() override

source/blender/nodes/composite/nodes/node_composite_mask.cc

@@ -101,8 +101,7 @@ class MaskOperation : public NodeOperation {
         get_motion_blur_samples(),
         get_motion_blur_shutter());
 
-    output_mask.allocate_texture(domain);
-    GPU_texture_copy(output_mask.texture(), cached_mask.texture());
+    output_mask.wrap_external(cached_mask.texture());
   }
 
   Domain compute_domain() override

source/blender/nodes/composite/nodes/node_composite_texture.cc

@@ -63,13 +63,11 @@ class TextureOperation : public NodeOperation {
         get_input("Scale").get_vector_value_default(float4(0.0f)).xy());
 
     if (color_result.should_compute()) {
-      color_result.allocate_texture(domain);
-      GPU_texture_copy(color_result.texture(), cached_texture.color_texture());
+      color_result.wrap_external(cached_texture.color_texture());
     }
 
     if (value_result.should_compute()) {
-      value_result.allocate_texture(domain);
-      GPU_texture_copy(value_result.texture(), cached_texture.value_texture());
+      value_result.wrap_external(cached_texture.value_texture());
     }
   }