Render API/Cycles: Identify Render Passes by their name instead of a type flag

Previously, every RenderPass would have a bitfield that specified its type. That limits the number of passes to 32, which was reached a while ago.
However, most of the code already supported arbitrary RenderPasses since they were also used to store Multilayer EXR images.
Therefore, this commit completely removes the passflag from RenderPass and changes all code to use the unique pass name for identification.
Since Blender Internal relies on hardcoded passes and to preserve compatibility, 32 pass names are reserved for the old hardcoded passes.

To support these arbitrary passes, the Render Result compositor node now adds dynamic sockets. For compatibility, the old hardcoded sockets are always stored and just hidden when the corresponding pass isn't available.

To use these changes, the Render Engine API now includes a function that allows render engines to add arbitrary passes to the render result. To be able to add options for these passes, addons can now add their own properties to SceneRenderLayers.
To keep the compositor input node updated, render engine plugins have to implement a callback that registers all the passes that will be generated.

From a user perspective, nothing should change with this commit.

Differential Revision: https://developer.blender.org/D2443

Differential Revision: https://developer.blender.org/D2444

3 files changed, 46 insertions, 63 deletions

diff --git a/source/blender/compositor/nodes/COM_ImageNode.cpp b/source/blender/compositor/nodes/COM_ImageNode.cpp
index facd422c217..462947f32a3 100644
--- a/source/blender/compositor/nodes/COM_ImageNode.cpp
+++ b/source/blender/compositor/nodes/COM_ImageNode.cpp
@@ -95,18 +95,10 @@ void ImageNode::convertToOperations(NodeConverter &converter, const CompositorCo
 					NodeOperation *operation = NULL;
 					socket = this->getOutputSocket(index);
 					bNodeSocket *bnodeSocket = socket->getbNodeSocket();
-					RenderPass *rpass = (RenderPass *)BLI_findstring(&rl->passes, bnodeSocket->identifier, offsetof(RenderPass, internal_name));
+					NodeImageLayer *storage = (NodeImageLayer *)bnodeSocket->storage;
+					RenderPass *rpass = (RenderPass *)BLI_findstring(&rl->passes, storage->pass_name, offsetof(RenderPass, name));
 					int view = 0;
 
-					/* Passes in the file can differ from passes stored in sockets (#36755).
-					 * Look up the correct file pass using the socket identifier instead.
-					 */
-#if 0
-					NodeImageLayer *storage = (NodeImageLayer *)bnodeSocket->storage;*/
-					int passindex = storage->pass_index;*/
-					RenderPass *rpass = (RenderPass *)BLI_findlink(&rl->passes, passindex);
-#endif
-
 					/* returns the image view to use for the current active view */
 					if (BLI_listbase_count_ex(&image->rr->views, 2) > 1) {
 						const int view_image = imageuser->view;
@@ -147,7 +139,7 @@ void ImageNode::convertToOperations(NodeConverter &converter, const CompositorCo
 						if (index == 0 && operation) {
 							converter.addPreview(operation->getOutputSocket());
 						}
-						if (rpass->passtype == SCE_PASS_COMBINED) {
+						if (STREQ(rpass->name, RE_PASSNAME_COMBINED)) {
 							BLI_assert(operation != NULL);
 							BLI_assert(index < numberOfOutputs - 1);
 							NodeOutput *outputSocket = this->getOutputSocket(index + 1);
diff --git a/source/blender/compositor/nodes/COM_RenderLayersNode.cpp b/source/blender/compositor/nodes/COM_RenderLayersNode.cpp
index 842edcf35c9..75128de2d84 100644
--- a/source/blender/compositor/nodes/COM_RenderLayersNode.cpp
+++ b/source/blender/compositor/nodes/COM_RenderLayersNode.cpp
@@ -27,76 +27,61 @@
 #include "COM_ScaleOperation.h"
 #include "COM_SetValueOperation.h"
 
-#ifdef WITH_CYCLES_DEBUG
-#  include "RE_pipeline.h"
-#endif
-
 RenderLayersNode::RenderLayersNode(bNode *editorNode) : Node(editorNode)
 {
 	/* pass */
 }
 
 void RenderLayersNode::testSocketLink(NodeConverter &converter, const CompositorContext &context,
-                                            int outputSocketNumber, RenderLayersBaseProg *operation) const
+                                      NodeOutput *output, RenderLayersProg *operation,
+                                      Scene *scene, int layerId, bool is_preview) const
 {
-	NodeOutput *outputSocket = this->getOutputSocket(outputSocketNumber);
-	Scene *scene = (Scene *)this->getbNode()->id;
-	short layerId = this->getbNode()->custom1;
-
 	operation->setScene(scene);
 	operation->setLayerId(layerId);
 	operation->setRenderData(context.getRenderData());
 	operation->setViewName(context.getViewName());
 
-	converter.mapOutputSocket(outputSocket, operation->getOutputSocket());
+	converter.mapOutputSocket(output, operation->getOutputSocket());
 	converter.addOperation(operation);
 	
-	if (outputSocketNumber == 0) /* only for image socket */
+	if (is_preview) /* only for image socket */
 		converter.addPreview(operation->getOutputSocket());
 }
 
 void RenderLayersNode::convertToOperations(NodeConverter &converter, const CompositorContext &context) const
 {
-	testSocketLink(converter, context, 0, new RenderLayersColorProg());
-	testSocketLink(converter, context, 1, new RenderLayersAlphaProg());
-	testSocketLink(converter, context, 2, new RenderLayersDepthProg());
-	testSocketLink(converter, context, 3, new RenderLayersNormalOperation());
-	testSocketLink(converter, context, 4, new RenderLayersUVOperation());
-	testSocketLink(converter, context, 5, new RenderLayersSpeedOperation());
-	testSocketLink(converter, context, 6, new RenderLayersColorOperation());
-	testSocketLink(converter, context, 7, new RenderLayersDiffuseOperation());
-	testSocketLink(converter, context, 8, new RenderLayersSpecularOperation());
-	testSocketLink(converter, context, 9, new RenderLayersShadowOperation());
-	testSocketLink(converter, context, 10, new RenderLayersAOOperation());
-	testSocketLink(converter, context, 11, new RenderLayersReflectionOperation());
-	testSocketLink(converter, context, 12, new RenderLayersRefractionOperation());
-	testSocketLink(converter, context, 13, new RenderLayersIndirectOperation());
-	testSocketLink(converter, context, 14, new RenderLayersObjectIndexOperation());
-	testSocketLink(converter, context, 15, new RenderLayersMaterialIndexOperation());
-	testSocketLink(converter, context, 16, new RenderLayersMistOperation());
-	testSocketLink(converter, context, 17, new RenderLayersEmitOperation());
-	testSocketLink(converter, context, 18, new RenderLayersEnvironmentOperation());
+	Scene *scene = (Scene *)this->getbNode()->id;
+	short layerId = this->getbNode()->custom1;
+	Render *re = (scene) ? RE_GetRender(scene->id.name) : NULL;
+	int numberOfOutputs = this->getNumberOfOutputSockets();
 	
-	// cycles passes
-	testSocketLink(converter, context, 19, new RenderLayersCyclesOperation(SCE_PASS_DIFFUSE_DIRECT));
-	testSocketLink(converter, context, 20, new RenderLayersCyclesOperation(SCE_PASS_DIFFUSE_INDIRECT));
-	testSocketLink(converter, context, 21, new RenderLayersCyclesOperation(SCE_PASS_DIFFUSE_COLOR));
-	testSocketLink(converter, context, 22, new RenderLayersCyclesOperation(SCE_PASS_GLOSSY_DIRECT));
-	testSocketLink(converter, context, 23, new RenderLayersCyclesOperation(SCE_PASS_GLOSSY_INDIRECT));
-	testSocketLink(converter, context, 24, new RenderLayersCyclesOperation(SCE_PASS_GLOSSY_COLOR));
-	testSocketLink(converter, context, 25, new RenderLayersCyclesOperation(SCE_PASS_TRANSM_DIRECT));
-	testSocketLink(converter, context, 26, new RenderLayersCyclesOperation(SCE_PASS_TRANSM_INDIRECT));
-	testSocketLink(converter, context, 27, new RenderLayersCyclesOperation(SCE_PASS_TRANSM_COLOR));
-	testSocketLink(converter, context, 28, new RenderLayersCyclesOperation(SCE_PASS_SUBSURFACE_DIRECT));
-	testSocketLink(converter, context, 29, new RenderLayersCyclesOperation(SCE_PASS_SUBSURFACE_INDIRECT));
-	testSocketLink(converter, context, 30, new RenderLayersCyclesOperation(SCE_PASS_SUBSURFACE_COLOR));
-
-#ifdef WITH_CYCLES_DEBUG
-	{
-		Scene *scene = (Scene *)this->getbNode()->id;
-		Render *re = RE_GetRender(scene->id.name);
-		int debug_pass_type = ((re != NULL) ? RE_debug_pass_type_get(re) : scene->r.debug_pass_type);
-		testSocketLink(converter, context, 31, new RenderLayersCyclesDebugOperation(SCE_PASS_DEBUG, debug_pass_type));
+	if (re) {
+		RenderResult *rr = RE_AcquireResultRead(re);
+		if (rr) {
+			SceneRenderLayer *srl = (SceneRenderLayer *)BLI_findlink(&scene->r.layers, layerId);
+			if (srl) {
+				RenderLayer *rl = RE_GetRenderLayer(rr, srl->name);
+				if (rl) {
+					for (int i = 0; i < numberOfOutputs; i++) {
+						NodeOutput *output = this->getOutputSocket(i);
+						NodeImageLayer *storage = (NodeImageLayer*) output->getbNodeSocket()->storage;
+						RenderPass *rpass = (RenderPass*) BLI_findstring(&rl->passes, storage->pass_name, offsetof(RenderPass, name));
+						if (rpass) {
+							if (STREQ(rpass->name, RE_PASSNAME_COMBINED) && STREQ(output->getbNodeSocket()->name, "Alpha")) {
+								testSocketLink(converter, context, output, new RenderLayersAlphaProg(rpass->name, COM_DT_VALUE, rpass->channels), scene, layerId, false);
+							}
+							else if (STREQ(rpass->name, RE_PASSNAME_Z)) {
+								testSocketLink(converter, context, output, new RenderLayersDepthProg(rpass->name, COM_DT_VALUE, rpass->channels), scene, layerId, false);
+							}
+							else {
+								DataType type = ((rpass->channels == 4)? COM_DT_COLOR : ((rpass->channels == 3)? COM_DT_VECTOR : COM_DT_VALUE));
+								testSocketLink(converter, context, output, new RenderLayersProg(rpass->name, type, rpass->channels), scene, layerId, STREQ(output->getbNodeSocket()->name, "Image"));
+							}
+						}
+					}
+				}
+			}
+		}
+		RE_ReleaseResult(re);
 	}
-#endif
 }
diff --git a/source/blender/compositor/nodes/COM_RenderLayersNode.h b/source/blender/compositor/nodes/COM_RenderLayersNode.h
index 5863cbb390c..1f733a9f4bb 100644
--- a/source/blender/compositor/nodes/COM_RenderLayersNode.h
+++ b/source/blender/compositor/nodes/COM_RenderLayersNode.h
@@ -33,5 +33,11 @@ public:
 	RenderLayersNode(bNode *editorNode);
 	void convertToOperations(NodeConverter &converter, const CompositorContext &context) const;
 private:
-	void testSocketLink(NodeConverter &converter, const CompositorContext &context, int outputSocketNumber, RenderLayersBaseProg *operation) const;
+	void testSocketLink(NodeConverter &converter,
+	                    const CompositorContext &context,
+	                    NodeOutput *output,
+	                    RenderLayersProg *operation,
+	                    Scene *scene,
+	                    int layerId,
+	                    bool is_preview) const;
 };