Mesa (nvfx-next-6): nvfx: use a CPU copy for up to 4 pixels, up from 0

[Luca Barbieri]

Module: Mesa
Branch: nvfx-next-6
Commit: 72027212debd0d2294e618dcb73736f15270f7cd
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=72027212debd0d2294e618dcb73736f15270f7cd

Author: Luca Barbieri <luca at luca-barbieri.com>
Date:   Sun Apr 18 16:43:19 2010 +0200

nvfx: use a CPU copy for up to 4 pixels, up from 0

Seems a reasonable threshold for now.

Significantly speeds up Piglit's 1x1 glReadPixels (but, you know,
reading pixels in 1x1 blocks is NOT a good idea, especially if you
might be running on a less-than-perfect driver).

---

 src/gallium/drivers/nvfx/nvfx_surface.c |    6 +-----
 1 files changed, 1 insertions(+), 5 deletions(-)

diff --git a/src/gallium/drivers/nvfx/nvfx_surface.c b/src/gallium/drivers/nvfx/nvfx_surface.c
index e7e68ed..ceeb6d4 100644
--- a/src/gallium/drivers/nvfx/nvfx_surface.c
+++ b/src/gallium/drivers/nvfx/nvfx_surface.c
@@ -172,11 +172,7 @@ nvfx_surface_copy(struct pipe_context* pipe, struct pipe_surface *dsts,
 
 	static int copy_threshold = -1;
 	if(copy_threshold < 0)
-	{
-		copy_threshold = debug_get_num_option("NOUVEAU_COPY_THRESHOLD", 0);
-		if(copy_threshold < 0)
-			copy_threshold = 0;
-	}
+		copy_threshold = debug_get_num_option("NOUVEAU_COPY_THRESHOLD", 4);
 
 	int dst_to_gpu = !(dsts->texture->_usage & PIPE_USAGE_DYNAMIC);;
 	int src_on_gpu = nouveau_resource_on_gpu(srcs->texture);