Cycles code internals: add support for mesh voxel grid attributes.

These are internally stored as a 3D image textures, but accessible like e.g.
UV coordinates though the attribute node and getattribute().

This is convenient for rendering e.g. smoke objects where data like density is
really a property of the mesh, and it avoids having to specify the smoke object
in a texture node, instead the material will work with any smoke domain.

2 files changed, 14 insertions, 35 deletions

diff --git a/intern/cycles/kernel/svm/svm_attribute.h b/intern/cycles/kernel/svm/svm_attribute.h
index 2592bbe575f..fd0ea7fef31 100644
--- a/intern/cycles/kernel/svm/svm_attribute.h
+++ b/intern/cycles/kernel/svm/svm_attribute.h
@@ -22,12 +22,12 @@ ccl_device void svm_node_attr_init(KernelGlobals *kg, ShaderData *sd,
 	uint4 node, NodeAttributeType *type,
 	NodeAttributeType *mesh_type, AttributeElement *elem, int *offset, uint *out_offset)
 {
-	if(sd->object != OBJECT_NONE && sd->prim != PRIM_NONE) {
+	if(sd->object != OBJECT_NONE) {
 		/* find attribute by unique id */
 		uint id = node.y;
 		uint attr_offset = sd->object*kernel_data.bvh.attributes_map_stride;
 #ifdef __HAIR__
-		attr_offset = (sd->type & PRIMITIVE_ALL_TRIANGLE)? attr_offset: attr_offset + ATTR_PRIM_CURVE;
+		attr_offset = (sd->type & PRIMITIVE_ALL_CURVE)? attr_offset + ATTR_PRIM_CURVE: attr_offset;
 #endif
 		uint4 attr_map = kernel_tex_fetch(__attributes_map, attr_offset);
 		
diff --git a/intern/cycles/kernel/svm/svm_tex_coord.h b/intern/cycles/kernel/svm/svm_tex_coord.h
index bddeac0b722..a17e4a25efe 100644
--- a/intern/cycles/kernel/svm/svm_tex_coord.h
+++ b/intern/cycles/kernel/svm/svm_tex_coord.h
@@ -70,17 +70,10 @@ ccl_device void svm_node_tex_coord(KernelGlobals *kg, ShaderData *sd, int path_f
 		case NODE_TEXCO_VOLUME_GENERATED: {
 			data = sd->P;
 
-			if(sd->object != OBJECT_NONE) {
-				AttributeElement attr_elem;
-				int attr_offset = find_attribute(kg, sd, ATTR_STD_GENERATED_TRANSFORM, &attr_elem);
-
-				object_inverse_position_transform(kg, sd, &data);
-
-				if(attr_offset != ATTR_STD_NOT_FOUND) {
-					Transform tfm = primitive_attribute_matrix(kg, sd, attr_offset);
-					data = transform_point(&tfm, data);
-				}
-			}
+#ifdef __VOLUME__
+			if(sd->object != OBJECT_NONE)
+				data = volume_normalized_position(kg, sd, data);
+#endif
 			break;
 		}
 	}
@@ -141,17 +134,10 @@ ccl_device void svm_node_tex_coord_bump_dx(KernelGlobals *kg, ShaderData *sd, in
 		case NODE_TEXCO_VOLUME_GENERATED: {
 			data = sd->P + sd->dP.dx;
 
-			if(sd->object != OBJECT_NONE) {
-				AttributeElement attr_elem;
-				int attr_offset = find_attribute(kg, sd, ATTR_STD_GENERATED_TRANSFORM, &attr_elem);
-
-				object_inverse_position_transform(kg, sd, &data);
-
-				if(attr_offset != ATTR_STD_NOT_FOUND) {
-					Transform tfm = primitive_attribute_matrix(kg, sd, attr_offset);
-					data = transform_point(&tfm, data);
-				}
-			}
+#ifdef __VOLUME__
+			if(sd->object != OBJECT_NONE)
+				data = volume_normalized_position(kg, sd, data);
+#endif
 			break;
 		}
 	}
@@ -215,17 +201,10 @@ ccl_device void svm_node_tex_coord_bump_dy(KernelGlobals *kg, ShaderData *sd, in
 		case NODE_TEXCO_VOLUME_GENERATED: {
 			data = sd->P + sd->dP.dy;
 
-			if(sd->object != OBJECT_NONE) {
-				AttributeElement attr_elem;
-				int attr_offset = find_attribute(kg, sd, ATTR_STD_GENERATED_TRANSFORM, &attr_elem);
-
-				object_inverse_position_transform(kg, sd, &data);
-
-				if(attr_offset != ATTR_STD_NOT_FOUND) {
-					Transform tfm = primitive_attribute_matrix(kg, sd, attr_offset);
-					data = transform_point(&tfm, data);
-				}
-			}
+#ifdef __VOLUME__
+			if(sd->object != OBJECT_NONE)
+				data = volume_normalized_position(kg, sd, data);
+#endif
 			break;
 		}
 	}