1 files changed, 13 insertions, 0 deletions
diff --git a/source/blender/compositor/operations/COM_SetAlphaReplaceOperation.cc b/source/blender/compositor/operations/COM_SetAlphaReplaceOperation.cc
index 90bfc814b09..434f5d9b63c 100644
--- a/source/blender/compositor/operations/COM_SetAlphaReplaceOperation.cc
+++ b/source/blender/compositor/operations/COM_SetAlphaReplaceOperation.cc
@@ -28,6 +28,7 @@ SetAlphaReplaceOperation::SetAlphaReplaceOperation()
 
   this->m_inputColor = nullptr;
   this->m_inputAlpha = nullptr;
+  this->flags.can_be_constant = true;
 }
 
 void SetAlphaReplaceOperation::initExecution()
@@ -54,4 +55,16 @@ void SetAlphaReplaceOperation::deinitExecution()
   this->m_inputAlpha = nullptr;
 }
 
+void SetAlphaReplaceOperation::update_memory_buffer_partial(MemoryBuffer *output,
+                                                            const rcti &area,
+                                                            Span<MemoryBuffer *> inputs)
+{
+  for (BuffersIterator<float> it = output->iterate_with(inputs, area); !it.is_end(); ++it) {
+    const float *color = it.in(0);
+    const float alpha = *it.in(1);
+    copy_v3_v3(it.out, color);
+    it.out[3] = alpha;
+  }
+}
+
 }  // namespace blender::compositor