Compositor: Full frame matte nodes

Adds full frame implementation to Channel Key, Chroma Key, Color Key,
Color Spill, Cryptomatte, Difference Key, Distance Key, Keying,
Keying Screen and Luminance Key nodes. The other nodes
in "Matte" sub-menu are submitted separately.

No functional changes.

Part of T88150.

Reviewed By: jbakker

Differential Revision: https://developer.blender.org/D12220

1 files changed, 41 insertions, 1 deletions

diff --git a/source/blender/compositor/operations/COM_DistanceRGBMatteOperation.cc b/source/blender/compositor/operations/COM_DistanceRGBMatteOperation.cc
index 1b3403cbb29..8155ff769a0 100644
--- a/source/blender/compositor/operations/COM_DistanceRGBMatteOperation.cc
+++ b/source/blender/compositor/operations/COM_DistanceRGBMatteOperation.cc
@@ -29,6 +29,7 @@ DistanceRGBMatteOperation::DistanceRGBMatteOperation()
 
   this->m_inputImageProgram = nullptr;
   this->m_inputKeyProgram = nullptr;
+  flags.can_be_constant = true;
 }
 
 void DistanceRGBMatteOperation::initExecution()
@@ -43,7 +44,7 @@ void DistanceRGBMatteOperation::deinitExecution()
   this->m_inputKeyProgram = nullptr;
 }
 
-float DistanceRGBMatteOperation::calculateDistance(float key[4], float image[4])
+float DistanceRGBMatteOperation::calculateDistance(const float key[4], const float image[4])
 {
   return len_v3v3(key, image);
 }
@@ -93,4 +94,43 @@ void DistanceRGBMatteOperation::executePixelSampled(float output[4],
   }
 }
 
+void DistanceRGBMatteOperation::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 *in_image = it.in(0);
+    const float *in_key = it.in(1);
+
+    float distance = this->calculateDistance(in_key, in_image);
+    const float tolerance = this->m_settings->t1;
+    const float falloff = this->m_settings->t2;
+
+    /* Store matte(alpha) value in [0] to go with
+     * COM_SetAlphaMultiplyOperation and the Value output.
+     */
+
+    /* Make 100% transparent. */
+    if (distance < tolerance) {
+      it.out[0] = 0.0f;
+    }
+    /* In the falloff region, make partially transparent. */
+    else if (distance < falloff + tolerance) {
+      distance = distance - tolerance;
+      const float alpha = distance / falloff;
+      /* Only change if more transparent than before. */
+      if (alpha < in_image[3]) {
+        it.out[0] = alpha;
+      }
+      else { /* Leave as before. */
+        it.out[0] = in_image[3];
+      }
+    }
+    else {
+      /* Leave as before. */
+      it.out[0] = in_image[3];
+    }
+  }
+}
+
 }  // namespace blender::compositor