diff options
| -rw-r--r-- | src/gallium/auxiliary/util/u_prim.h | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/src/gallium/auxiliary/util/u_prim.h b/src/gallium/auxiliary/util/u_prim.h index ae05788702c..d80e235ffd9 100644 --- a/src/gallium/auxiliary/util/u_prim.h +++ b/src/gallium/auxiliary/util/u_prim.h @@ -327,6 +327,25 @@ u_vertices_for_prims(enum pipe_prim_type prim_type, int count) return info->min + (count - 1) * info->incr; } +/** + * Returns the number of stream out outputs for a given number of vertices and + * primitive type. + */ + +static inline unsigned +u_stream_outputs_for_vertices(enum pipe_prim_type primitive, unsigned nr) +{ + /* Extraneous vertices don't contribute to stream outputs */ + u_trim_pipe_prim(primitive, &nr); + + /* Consider how many primitives are actually generated */ + unsigned prims = u_decomposed_prims_for_vertices(primitive, nr); + + /* One output per vertex after decomposition */ + enum pipe_prim_type base = u_base_prim_type(primitive); + return u_vertices_for_prims(base, prims); +} + const char *u_prim_name(enum pipe_prim_type pipe_prim); |