GeomRayserverInstancer User Attributes per instance

[jbvfx]

Hi,

I'm using the GeomRayserverInstancer to generate millions of instances. Everything works except I can't get user attributes to work.
I want to assign a user attribute to each instance. ie "rand= (random number from 0 to 1)"

In the documentation there's different functions for setting user attributes, but it looks like "set_user_attributes_bin", is the one to use.
The argument for this function is an intList, so I guess I need to convert my CharString to a byte int?
The documentation also says to refer to "BinUserAttributesWriter". Where can I find information about that?

[bdancer]

If you have access to V-Ray SDK it's defined in user_attributes.h.
It's basically a simple binary packer.

const char attrRand[] = "rand";
const int atttrRandLen = COUNT_OF(attrRand)-1;

VUtils::BinUserAttributesWriter userAttrBin;

// Instance 1.
userAttrBin.add(attrRand, atttrRandLen, 0.5f);
userAttrBin.close();

// Instance 2 no attributes.
userAttrBin.close();

// Instance 3.
userAttrBin.add(attrRand, atttrRandLen, 0.1f);
userAttrBin.close();

const VUtils::IntRefList uaBin = userAttrBin.toRefList();
const VRay::VUtils::IntRefList attributes = *reinterpret_cast<const VRay::VUtils::IntRefList*>(&uaBin)

plugin.set_user_attributes_bin(attributes)

[jbvfx]

Works like a charm.

Thanks!

[jbvfx]

Another question.

Is it possible to switch geometry source per instance? Similar to the shaders/shader_indexes.

[hypotheticalinc]

I'm trying to do the same thing in the 5.10.01 SDK and I don't see

VUtils::BinUserAttributesWriter

anywhere. Is there a new recommended way of packing the binary data into an IntList?

[hypotheticalinc]

Ahhhh, never mind. I didn't catch that it is in the VRay SDK, not the AppSDK. Carry on.

[stanislav.kirilov]

BinUserAttributesWriter is available for testing now in V-Ray AppSDK nightly builds (currently in C++ only).