gallium: add PIPE_CAP_CONSTANT_BUFFER_OFFSET_ALIGNMENT

This is required for any serious constant buffer support.
Constant buffer offsets on ATI and NVIDIA DX10 and DX11 GPUs must be
a multiple of 256.

In OpenGL, this can be queried via GL_UNIFORM_BUFFER_OFFSET_ALIGNMENT.

1 files changed, 2 insertions, 0 deletions

diff --git a/src/gallium/drivers/softpipe/sp_screen.c b/src/gallium/drivers/softpipe/sp_screen.c
index ec8acebf913..cdc78676655 100644
--- a/src/gallium/drivers/softpipe/sp_screen.c
+++ b/src/gallium/drivers/softpipe/sp_screen.c
@@ -142,6 +142,8 @@ softpipe_get_param(struct pipe_screen *screen, enum pipe_cap param)
    case PIPE_CAP_USER_INDEX_BUFFERS:
    case PIPE_CAP_USER_CONSTANT_BUFFERS:
       return 1;
+   case PIPE_CAP_CONSTANT_BUFFER_OFFSET_ALIGNMENT:
+      return 16;
    default:
       return 0;
    }