[Mesa-dev] [PATCH] gallium/tests/trivial: fix viewport depth transform

[Roland Scheidegger]

I suppose that's ok (and safer), albeit I'm not sure why it wouldn't
work with nv50.
Depth clip is enabled, yes, but I can't see why the produced values
wouldn't be inside the view volume (which is defined by the near/far
values for z).
Granted values outside [0,1] are not permitted by standard GL, but
there's extensions for it (NV_depth_buffer_float), so I'm a bit confused.

Reviewed-by: Roland Scheidegger <sroland at vmware.com>


Am 01.03.2018 um 01:43 schrieb Ilia Mirkin:
> These were getting mapped off into outer space, which would cause nv50
> and nvc0 to clip the primitives (as depth_clip was enabled).
> 
> Oddly enough, it worked with nv30 and llvmpipe though. Perhaps their
> frustrum clipping rules are a bit different?
> 
> Signed-off-by: Ilia Mirkin <imirkin at alum.mit.edu>
> ---
>  src/gallium/tests/trivial/quad-tex.c | 7 ++++---
>  src/gallium/tests/trivial/tri.c      | 6 +++---
>  2 files changed, 7 insertions(+), 6 deletions(-)
> 
> diff --git a/src/gallium/tests/trivial/quad-tex.c b/src/gallium/tests/trivial/quad-tex.c
> index df0e1301f5e..1f29306ec04 100644
> --- a/src/gallium/tests/trivial/quad-tex.c
> +++ b/src/gallium/tests/trivial/quad-tex.c
> @@ -27,8 +27,8 @@
>  #define USE_TRACE 0
>  #define WIDTH 300
>  #define HEIGHT 300
> -#define NEAR 30
> -#define FAR 1000
> +#define NEAR 0
> +#define FAR 1
>  #define FLIP 0
>  
>  /* pipe_*_state structs */
> @@ -174,6 +174,7 @@ static void init_prog(struct program *p)
>  		memset(&box, 0, sizeof(box));
>  		box.width = 2;
>  		box.height = 2;
> +		box.depth = 1;
>  
>  		ptr = p->pipe->transfer_map(p->pipe, p->tex, 0, PIPE_TRANSFER_WRITE, &box, &t);
>  		ptr[0] = 0xffff0000;
> @@ -226,7 +227,7 @@ static void init_prog(struct program *p)
>  	{
>  		float x = 0;
>  		float y = 0;
> -		float z = FAR;
> +		float z = NEAR;
>  		float half_width = (float)WIDTH / 2.0f;
>  		float half_height = (float)HEIGHT / 2.0f;
>  		float half_depth = ((float)FAR - (float)NEAR) / 2.0f;
> diff --git a/src/gallium/tests/trivial/tri.c b/src/gallium/tests/trivial/tri.c
> index 71e97022752..87a335fba1e 100644
> --- a/src/gallium/tests/trivial/tri.c
> +++ b/src/gallium/tests/trivial/tri.c
> @@ -27,8 +27,8 @@
>  #define USE_TRACE 0
>  #define WIDTH 300
>  #define HEIGHT 300
> -#define NEAR 30
> -#define FAR 1000
> +#define NEAR 0
> +#define FAR 1
>  #define FLIP 0
>  
>  /* pipe_*_state structs */
> @@ -171,7 +171,7 @@ static void init_prog(struct program *p)
>  	{
>  		float x = 0;
>  		float y = 0;
> -		float z = FAR;
> +		float z = NEAR;
>  		float half_width = (float)WIDTH / 2.0f;
>  		float half_height = (float)HEIGHT / 2.0f;
>  		float half_depth = ((float)FAR - (float)NEAR) / 2.0f;
>