gallium: Add PIPE_BUFFER_USAGE_DISCARD.

When passed to map() signals that the buffer's previous contents are
not required, allowing the driver to allocate a new buffer if the
current buffer can not be mapped immediately.

diff --git a/src/gallium/include/pipe/p_defines.h b/src/gallium/include/pipe/p_defines.h
index 5c6a92b53bc5bb39d6454b496b9e17770c3b5eb1..4f0b301f3173fa64b8d5fcb14b1264aee656d267 100644 (file)
--- a/src/gallium/include/pipe/p_defines.h
+++ b/src/gallium/include/pipe/p_defines.h
@@ -204,6 +204,7 @@ enum pipe_texture_target {
 #define PIPE_BUFFER_USAGE_VERTEX    (1 << 5)
 #define PIPE_BUFFER_USAGE_INDEX     (1 << 6)
 #define PIPE_BUFFER_USAGE_CONSTANT  (1 << 7)
+#define PIPE_BUFFER_USAGE_DISCARD   (1 << 8)
 /** Pipe driver custom usage flags should be greater or equal to this value */
 #define PIPE_BUFFER_USAGE_CUSTOM    (1 << 16)