Fix T87194: custom attributes not accessible with Cycles Volume

Custom properties defined on objects are not accessible from the
attribute node when rendering a volume in Cycles. This is because
this case is not handled.

To handle it, added a primitive type for volumes in the kernel,
which is then used in the initialization of ShaderData and to
check whether an attribute lookup is for a volume.

`volume_attribute_float4` is also now checking the attribute
element type to dispatch to the right lookup function.

Reviewed By: #cycles, brecht

Maniphest Tasks: T87194

Differential Revision: https://developer.blender.org/D11728

1 files changed, 1 insertions, 1 deletions

diff --git a/intern/cycles/kernel/geom/geom_primitive.h b/intern/cycles/kernel/geom/geom_primitive.h
index 2c31e5cee03..aeb044c9ad3 100644
--- a/intern/cycles/kernel/geom/geom_primitive.h
+++ b/intern/cycles/kernel/geom/geom_primitive.h
@@ -138,7 +138,7 @@ ccl_device_inline float4 primitive_surface_attribute_float4(KernelGlobals *kg,
 ccl_device_inline bool primitive_is_volume_attribute(const ShaderData *sd,
                                                      const AttributeDescriptor desc)
 {
-  return (sd->object != OBJECT_NONE && desc.element == ATTR_ELEMENT_VOXEL);
+  return sd->type == PRIMITIVE_VOLUME;
 }
 
 ccl_device_inline float primitive_volume_attribute_float(KernelGlobals *kg,