gallium: add facilities for indirect drawing

v2:
Added comments to util_draw_indirect, clarified and fixed map size.
Removed unlikely().

2 files changed, 23 insertions, 0 deletions

diff --git a/src/gallium/include/pipe/p_defines.h b/src/gallium/include/pipe/p_defines.h
index 0c958cf050a..166391d6988 100644
--- a/src/gallium/include/pipe/p_defines.h
+++ b/src/gallium/include/pipe/p_defines.h
@@ -561,6 +561,7 @@ enum pipe_cap {
    PIPE_CAP_TEXTURE_GATHER_OFFSETS = 98,
    PIPE_CAP_TGSI_VS_WINDOW_SPACE_POSITION = 99,
    PIPE_CAP_MAX_VERTEX_STREAMS = 100,
+   PIPE_CAP_DRAW_INDIRECT = 101,
 };
 
 #define PIPE_QUIRK_TEXTURE_BORDER_COLOR_SWIZZLE_NV50 (1 << 0)
diff --git a/src/gallium/include/pipe/p_state.h b/src/gallium/include/pipe/p_state.h
index 6e6f88e6133..a82686b23a4 100644
--- a/src/gallium/include/pipe/p_state.h
+++ b/src/gallium/include/pipe/p_state.h
@@ -570,6 +570,28 @@ struct pipe_draw_info
     * be set via set_vertex_buffers manually.
     */
    struct pipe_stream_output_target *count_from_stream_output;
+
+   /* Indirect parameters resource: If not NULL, most values are taken
+    * from this buffer instead, which is laid out as follows:
+    *
+    * if indexed is TRUE:
+    *  struct {
+    *     uint32_t count;
+    *     uint32_t instance_count;
+    *     uint32_t start;
+    *     int32_t index_bias;
+    *     uint32_t start_instance;
+    *  };
+    * otherwise:
+    *  struct {
+    *     uint32_t count;
+    *     uint32_t instance_count;
+    *     uint32_t start;
+    *     uint32_t start_instance;
+    *  };
+    */
+   struct pipe_resource *indirect;
+   unsigned indirect_offset; /**< must be 4 byte aligned */
 };