* \param index_bounds_valid are min_index and max_index valid?
* \param min_index lowest vertex index used
* \param max_index highest vertex index used
+ * \param num_instances instance count from ARB_draw_instanced
+ * \param base_instance base instance from ARB_base_instance
* \param tfb_vertcount if non-null, indicates which transform feedback
* object has the vertex count.
* \param tfb_stream If called via DrawTransformFeedbackStream, specifies
const struct _mesa_index_buffer *ib,
GLboolean index_bounds_valid,
GLuint min_index, GLuint max_index,
+ GLuint num_instances, GLuint base_instance,
struct gl_transform_feedback_object *tfb_vertcount,
unsigned tfb_stream);