Compositor: Redesign Cryptomatte node for better usability

In the current implementation, cryptomatte passes are connected to the node
and elements are picked by using the eyedropper tool on a special pick channel.

This design has two disadvantages - both connecting all passes individually
and always having to switch to the picker channel are tedious.

With the new design, the user selects the RenderLayer or Image from which the
Cryptomatte layers are directly loaded (the type of pass is determined by an
enum). This allows the node to automatically detect all relevant passes.

Then, when using the eyedropper tool, the operator looks up the selected
coordinates from the picked Image, Node backdrop or Clip and reads the picked
object directly from the Renderlayer/Image, therefore allowing to pick in any
context (e.g. by clicking on the Combined pass in the Image Viewer). The
sampled color is looked up in the metadata and the actual name is stored
in the cryptomatte node. This also allows to remove a hash by just removing
the name from the matte id.

Technically there is some loss of flexibility because the Cryptomatte pass
inputs can no longer be connected to other nodes, but since any compositing
done on them is likely to break the Cryptomatte system anyways, this isn't
really a concern in practise.

In the future, this would also allow to automatically translate values to names
by looking up the value in the associated metadata of the input, or to get a
better visualization of overlapping areas in the Pick output since we could
blend colors now that the output doesn't have to contain the exact value.

Idea + Original patch: Lucas Stockner
Reviewed By: Brecht van Lommel

Differential Revision: https://developer.blender.org/D3959

1 files changed, 219 insertions, 36 deletions

diff --git a/source/blender/compositor/nodes/COM_CryptomatteNode.cc b/source/blender/compositor/nodes/COM_CryptomatteNode.cc
index 27ef98af8f3..4c698b5609f 100644
--- a/source/blender/compositor/nodes/COM_CryptomatteNode.cc
+++ b/source/blender/compositor/nodes/COM_CryptomatteNode.cc
@@ -17,64 +17,247 @@
  */
 
 #include "COM_CryptomatteNode.h"
-#include "COM_ConvertOperation.h"
-#include "COM_CryptomatteOperation.h"
-
+#include "BKE_node.h"
 #include "BLI_assert.h"
 #include "BLI_hash_mm3.h"
 #include "BLI_listbase.h"
 #include "BLI_string.h"
-
+#include "COM_ConvertOperation.h"
+#include "COM_CryptomatteOperation.h"
+#include "COM_MultilayerImageOperation.h"
+#include "COM_RenderLayersProg.h"
 #include "COM_SetAlphaMultiplyOperation.h"
+#include "COM_SetColorOperation.h"
 #include <iterator>
+#include <string>
+
+/** \name Cryptomatte base
+ * \{ */
 
-CryptomatteNode::CryptomatteNode(bNode *editorNode) : Node(editorNode)
+void CryptomatteBaseNode::convertToOperations(NodeConverter &converter,
+                                              const CompositorContext &context) const
 {
-  /* pass */
+  NodeOutput *output_image_socket = this->getOutputSocket(0);
+
+  bNode *node = this->getbNode();
+  NodeCryptomatte *cryptomatte_settings = static_cast<NodeCryptomatte *>(node->storage);
+
+  CryptomatteOperation *cryptomatte_operation = create_cryptomatte_operation(
+      converter, context, *node, cryptomatte_settings);
+  converter.addOperation(cryptomatte_operation);
+
+  NodeOutput *output_matte_socket = this->getOutputSocket(1);
+  SeparateChannelOperation *extract_mask_operation = new SeparateChannelOperation;
+  extract_mask_operation->setChannel(3);
+  converter.addOperation(extract_mask_operation);
+  converter.addLink(cryptomatte_operation->getOutputSocket(0),
+                    extract_mask_operation->getInputSocket(0));
+  converter.mapOutputSocket(output_matte_socket, extract_mask_operation->getOutputSocket(0));
+
+  NodeInput *input_image_socket = this->getInputSocket(0);
+  SetAlphaMultiplyOperation *apply_mask_operation = new SetAlphaMultiplyOperation();
+  converter.mapInputSocket(input_image_socket, apply_mask_operation->getInputSocket(0));
+  converter.addOperation(apply_mask_operation);
+  converter.addLink(extract_mask_operation->getOutputSocket(0),
+                    apply_mask_operation->getInputSocket(1));
+  converter.mapOutputSocket(output_image_socket, apply_mask_operation->getOutputSocket(0));
+
+  NodeOutput *output_pick_socket = this->getOutputSocket(2);
+  SetAlphaMultiplyOperation *extract_pick_operation = new SetAlphaMultiplyOperation();
+  converter.addOperation(extract_pick_operation);
+  converter.addInputValue(extract_pick_operation->getInputSocket(1), 1.0f);
+  converter.addLink(cryptomatte_operation->getOutputSocket(0),
+                    extract_pick_operation->getInputSocket(0));
+  converter.mapOutputSocket(output_pick_socket, extract_pick_operation->getOutputSocket(0));
 }
 
-void CryptomatteNode::convertToOperations(NodeConverter &converter,
-                                          const CompositorContext & /*context*/) const
+/* \} */
+
+/** \name Cryptomatte V2
+ * \{ */
+static std::string prefix_from_node(const bNode &node)
 {
-  NodeInput *inputSocketImage = this->getInputSocket(0);
-  NodeOutput *outputSocketImage = this->getOutputSocket(0);
-  NodeOutput *outputSocketMatte = this->getOutputSocket(1);
-  NodeOutput *outputSocketPick = this->getOutputSocket(2);
+  char prefix[MAX_NAME];
+  ntreeCompositCryptomatteLayerPrefix(&node, prefix, sizeof(prefix));
+  return std::string(prefix, BLI_strnlen(prefix, sizeof(prefix)));
+}
 
-  bNode *node = this->getbNode();
-  NodeCryptomatte *cryptoMatteSettings = (NodeCryptomatte *)node->storage;
+static std::string combined_layer_pass_name(RenderLayer *render_layer, RenderPass *render_pass)
+{
+  if (render_layer->name[0] == '\0') {
+    return std::string(render_pass->name,
+                       BLI_strnlen(render_pass->name, sizeof(render_pass->name)));
+  }
 
-  CryptomatteOperation *operation = new CryptomatteOperation(getNumberOfInputSockets() - 1);
-  if (cryptoMatteSettings) {
-    LISTBASE_FOREACH (CryptomatteEntry *, cryptomatte_entry, &cryptoMatteSettings->entries) {
-      operation->addObjectIndex(cryptomatte_entry->encoded_hash);
+  std::string combined_name =
+      blender::StringRef(render_layer->name,
+                         BLI_strnlen(render_layer->name, sizeof(render_layer->name))) +
+      "." +
+      blender::StringRef(render_pass->name,
+                         BLI_strnlen(render_pass->name, sizeof(render_pass->name)));
+  return combined_name;
+}
+
+void CryptomatteNode::input_operations_from_render_source(
+    const CompositorContext &context,
+    const bNode &node,
+    blender::Vector<NodeOperation *> &r_input_operations)
+{
+  Scene *scene = (Scene *)node.id;
+  if (!scene) {
+    return;
+  }
+
+  BLI_assert(GS(scene->id.name) == ID_SCE);
+  Render *render = RE_GetSceneRender(scene);
+  RenderResult *render_result = render ? RE_AcquireResultRead(render) : nullptr;
+
+  if (!render_result) {
+    return;
+  }
+
+  const short cryptomatte_layer_id = 0;
+  const std::string prefix = prefix_from_node(node);
+  LISTBASE_FOREACH (ViewLayer *, view_layer, &scene->view_layers) {
+    RenderLayer *render_layer = RE_GetRenderLayer(render_result, view_layer->name);
+    if (render_layer) {
+      LISTBASE_FOREACH (RenderPass *, render_pass, &render_layer->passes) {
+        const std::string combined_name = combined_layer_pass_name(render_layer, render_pass);
+        if (blender::StringRef(combined_name).startswith(prefix)) {
+          RenderLayersProg *op = new RenderLayersProg(
+              render_pass->name, COM_DT_COLOR, render_pass->channels);
+          op->setScene(scene);
+          op->setLayerId(cryptomatte_layer_id);
+          op->setRenderData(context.getRenderData());
+          op->setViewName(context.getViewName());
+          r_input_operations.append(op);
+        }
+      }
     }
   }
+  RE_ReleaseResult(render);
+}
 
-  converter.addOperation(operation);
+void CryptomatteNode::input_operations_from_image_source(
+    const CompositorContext &context,
+    const bNode &node,
+    blender::Vector<NodeOperation *> &r_input_operations)
+{
+  NodeCryptomatte *cryptomatte_settings = (NodeCryptomatte *)node.storage;
+  Image *image = (Image *)node.id;
+  if (!image) {
+    return;
+  }
 
-  for (int i = 0; i < getNumberOfInputSockets() - 1; i++) {
-    converter.mapInputSocket(this->getInputSocket(i + 1), operation->getInputSocket(i));
+  BLI_assert(GS(image->id.name) == ID_IM);
+  if (image->type != IMA_TYPE_MULTILAYER) {
+    return;
   }
 
-  SeparateChannelOperation *separateOperation = new SeparateChannelOperation;
-  separateOperation->setChannel(3);
-  converter.addOperation(separateOperation);
+  ImageUser *iuser = &cryptomatte_settings->iuser;
+  BKE_image_user_frame_calc(image, iuser, context.getFramenumber());
+  ImBuf *ibuf = BKE_image_acquire_ibuf(image, iuser, nullptr);
 
-  SetAlphaMultiplyOperation *operationAlpha = new SetAlphaMultiplyOperation();
-  converter.addOperation(operationAlpha);
+  if (image->rr) {
+    int view = 0;
+    if (BLI_listbase_count_at_most(&image->rr->views, 2) > 1) {
+      if (iuser->view == 0) {
+        /* Heuristic to match image name with scene names, check if the view name exists in the
+         * image. */
+        view = BLI_findstringindex(
+            &image->rr->views, context.getViewName(), offsetof(RenderView, name));
+        if (view == -1) {
+          view = 0;
+        }
+      }
+      else {
+        view = iuser->view - 1;
+      }
+    }
 
-  converter.addLink(operation->getOutputSocket(0), separateOperation->getInputSocket(0));
-  converter.addLink(separateOperation->getOutputSocket(0), operationAlpha->getInputSocket(1));
+    const std::string prefix = prefix_from_node(node);
+    LISTBASE_FOREACH (RenderLayer *, render_layer, &image->rr->layers) {
+      LISTBASE_FOREACH (RenderPass *, render_pass, &render_layer->passes) {
+        const std::string combined_name = combined_layer_pass_name(render_layer, render_pass);
+        if (blender::StringRef(combined_name).startswith(prefix)) {
+          MultilayerColorOperation *op = new MultilayerColorOperation(
+              render_layer, render_pass, view);
+          op->setImage(image);
+          op->setImageUser(iuser);
+          op->setFramenumber(context.getFramenumber());
+          r_input_operations.append(op);
+        }
+      }
+    }
+  }
+  BKE_image_release_ibuf(image, ibuf, nullptr);
+}
 
-  SetAlphaMultiplyOperation *clearAlphaOperation = new SetAlphaMultiplyOperation();
-  converter.addOperation(clearAlphaOperation);
-  converter.addInputValue(clearAlphaOperation->getInputSocket(1), 1.0f);
+blender::Vector<NodeOperation *> CryptomatteNode::create_input_operations(
+    const CompositorContext &context, const bNode &node)
+{
+  blender::Vector<NodeOperation *> input_operations;
+  switch (node.custom1) {
+    case CMP_CRYPTOMATTE_SRC_RENDER:
+      input_operations_from_render_source(context, node, input_operations);
+      break;
+    case CMP_CRYPTOMATTE_SRC_IMAGE:
+      input_operations_from_image_source(context, node, input_operations);
+      break;
+  }
 
-  converter.addLink(operation->getOutputSocket(0), clearAlphaOperation->getInputSocket(0));
+  if (input_operations.is_empty()) {
+    SetColorOperation *op = new SetColorOperation();
+    op->setChannel1(0.0f);
+    op->setChannel2(1.0f);
+    op->setChannel3(0.0f);
+    op->setChannel4(0.0f);
+    input_operations.append(op);
+  }
+  return input_operations;
+}
+CryptomatteOperation *CryptomatteNode::create_cryptomatte_operation(
+    NodeConverter &converter,
+    const CompositorContext &context,
+    const bNode &node,
+    const NodeCryptomatte *cryptomatte_settings) const
+{
+  blender::Vector<NodeOperation *> input_operations = create_input_operations(context, node);
+  CryptomatteOperation *operation = new CryptomatteOperation(input_operations.size());
+  LISTBASE_FOREACH (CryptomatteEntry *, cryptomatte_entry, &cryptomatte_settings->entries) {
+    operation->addObjectIndex(cryptomatte_entry->encoded_hash);
+  }
+  for (int i = 0; i < input_operations.size(); ++i) {
+    converter.addOperation(input_operations[i]);
+    converter.addLink(input_operations[i]->getOutputSocket(), operation->getInputSocket(i));
+  }
+  return operation;
+}
+
+/* \} */
+
+/** \name Cryptomatte legacy
+ * \{ */
 
-  converter.mapInputSocket(inputSocketImage, operationAlpha->getInputSocket(0));
-  converter.mapOutputSocket(outputSocketMatte, separateOperation->getOutputSocket(0));
-  converter.mapOutputSocket(outputSocketImage, operationAlpha->getOutputSocket(0));
-  converter.mapOutputSocket(outputSocketPick, clearAlphaOperation->getOutputSocket(0));
+CryptomatteOperation *CryptomatteLegacyNode::create_cryptomatte_operation(
+    NodeConverter &converter,
+    const CompositorContext &UNUSED(context),
+    const bNode &UNUSED(node),
+    const NodeCryptomatte *cryptomatte_settings) const
+{
+  const int num_inputs = getNumberOfInputSockets() - 1;
+  CryptomatteOperation *operation = new CryptomatteOperation(num_inputs);
+  if (cryptomatte_settings) {
+    LISTBASE_FOREACH (CryptomatteEntry *, cryptomatte_entry, &cryptomatte_settings->entries) {
+      operation->addObjectIndex(cryptomatte_entry->encoded_hash);
+    }
+  }
+
+  for (int i = 0; i < num_inputs; i++) {
+    converter.mapInputSocket(this->getInputSocket(i + 1), operation->getInputSocket(i));
+  }
+
+  return operation;
 }
+
+/* \} */
\ No newline at end of file