Cycles: Fix wrong closure counter in feature adaptive kernel

Some closures were missing from calculation, leading to an array
under-allocation, presumable causing memory corruption issues with
emission shaders on OpenCL and was causing issues with Volume 3D
textures with CUDA.

The issue was identified by Thomas Dinges, the patch is different
from the original D2006. See the brief discussion there. Current
approach is similar (or the same) as Brecht suggested.

4 files changed, 24 insertions, 11 deletions

diff --git a/intern/cycles/kernel/svm/svm_types.h b/intern/cycles/kernel/svm/svm_types.h
index 8c69c589ebb..be87e35326e 100644
--- a/intern/cycles/kernel/svm/svm_types.h
+++ b/intern/cycles/kernel/svm/svm_types.h
@@ -370,6 +370,9 @@ typedef enum ShaderType {
 /* Closure */
 
 typedef enum ClosureType {
+	/* Special type, flags generic node as a non-BSDF. */
+	CLOSURE_NONE_ID,
+
 	CLOSURE_BSDF_ID,
 
 	/* Diffuse */
diff --git a/intern/cycles/render/graph.cpp b/intern/cycles/render/graph.cpp
index 15c89cc4b51..24e4c9f33d5 100644
--- a/intern/cycles/render/graph.cpp
+++ b/intern/cycles/render/graph.cpp
@@ -984,17 +984,18 @@ int ShaderGraph::get_num_closures()
 {
 	int num_closures = 0;
 	foreach(ShaderNode *node, nodes) {
-		if(node->special_type == SHADER_SPECIAL_TYPE_CLOSURE) {
-			BsdfNode *bsdf_node = static_cast<BsdfNode*>(node);
-			/* TODO(sergey): Make it more generic approach, maybe some utility
-			 * macros like CLOSURE_IS_FOO()?
-			 */
-			if(CLOSURE_IS_BSSRDF(bsdf_node->closure))
-				num_closures = num_closures + 3;
-			else if(CLOSURE_IS_GLASS(bsdf_node->closure))
-				num_closures = num_closures + 2;
-			else
-				num_closures = num_closures + 1;
+		ClosureType closure_type = node->get_closure_type();
+		if(closure_type == CLOSURE_NONE_ID) {
+			continue;
+		}
+		else if(CLOSURE_IS_BSSRDF(closure_type)) {
+			num_closures += 3;
+		}
+		else if(CLOSURE_IS_GLASS(closure_type)) {
+			num_closures += 2;
+		}
+		else {
+			++num_closures;
 		}
 	}
 	return num_closures;
diff --git a/intern/cycles/render/graph.h b/intern/cycles/render/graph.h
index b1ebdbfd51d..bd3f5ca689a 100644
--- a/intern/cycles/render/graph.h
+++ b/intern/cycles/render/graph.h
@@ -237,6 +237,9 @@ public:
 	 */
 	virtual int get_feature() { return bump == SHADER_BUMP_NONE ? 0 : NODE_FEATURE_BUMP; }
 
+	/* Get closure ID to which the node compiles into. */
+	virtual ClosureType get_closure_type() { return CLOSURE_NONE_ID; }
+
 	/* Check whether settings of the node equals to another one.
 	 *
 	 * This is mainly used to check whether two nodes can be merged
diff --git a/intern/cycles/render/nodes.h b/intern/cycles/render/nodes.h
index 54a5220dcef..5df34a84559 100644
--- a/intern/cycles/render/nodes.h
+++ b/intern/cycles/render/nodes.h
@@ -387,6 +387,7 @@ public:
 
 	bool has_spatial_varying() { return true; }
 	void compile(SVMCompiler& compiler, ShaderInput *param1, ShaderInput *param2, ShaderInput *param3 = NULL, ShaderInput *param4 = NULL);
+	virtual ClosureType get_closure_type() { return closure; }
 
 	ClosureType closure;
 	bool scattering;
@@ -484,6 +485,7 @@ class EmissionNode : public ShaderNode {
 public:
 	SHADER_NODE_CLASS(EmissionNode)
 	bool constant_fold(ShaderGraph *graph, ShaderOutput *socket, float3 *optimized_value);
+	virtual ClosureType get_closure_type() { return CLOSURE_EMISSION_ID; }
 
 	bool has_surface_emission() { return true; }
 };
@@ -492,12 +494,14 @@ class BackgroundNode : public ShaderNode {
 public:
 	SHADER_NODE_CLASS(BackgroundNode)
 	bool constant_fold(ShaderGraph *graph, ShaderOutput *socket, float3 *optimized_value);
+	virtual ClosureType get_closure_type() { return CLOSURE_BACKGROUND_ID; }
 };
 
 class HoldoutNode : public ShaderNode {
 public:
 	SHADER_NODE_CLASS(HoldoutNode)
 	virtual int get_group() { return NODE_GROUP_LEVEL_1; }
+	virtual ClosureType get_closure_type() { return CLOSURE_HOLDOUT_ID; }
 };
 
 class AmbientOcclusionNode : public ShaderNode {
@@ -506,6 +510,7 @@ public:
 
 	bool has_spatial_varying() { return true; }
 	virtual int get_group() { return NODE_GROUP_LEVEL_1; }
+	virtual ClosureType get_closure_type() { return CLOSURE_AMBIENT_OCCLUSION_ID; }
 };
 
 class VolumeNode : public ShaderNode {
@@ -517,6 +522,7 @@ public:
 	virtual int get_feature() {
 		return ShaderNode::get_feature() | NODE_FEATURE_VOLUME;
 	}
+	virtual ClosureType get_closure_type() { return closure; }
 
 	ClosureType closure;