| attr | The vertex data attribute to check for. |
int Stream index of the data attribute, or -1 if it is not present.
Get the vertex buffer stream index of a specific vertex data attribute on this MeshData.
Meshes usually use a single vertex buffer stream, but it is possible to set up a vertex layout where attributes
use different vertex buffers (see SetVertexBufferParams). When you use such a layout, use this function to query which vertex buffer stream a given attribute is part of.
Note that this function returns the index of the stream, without specifying where the attribute is within the stream. To identify the location of a given attribute in the stream, use GetVertexAttributeOffset.
Additional resources: GetVertexAttributeOffset, vertexBufferCount, GetVertexBufferStride, Mesh.GetVertexAttributeStream.