[Piglit] [PATCH] glx-swap-pixmap: Expect alpha = 1.0 if there is no alpha in the pixmap

[Brian Paul]

On 01/28/2013 05:39 PM, Ian Romanick wrote:
> From: Ian Romanick<ian.d.romanick at intel.com>
>
> Signed-off-by: Ian Romanick<ian.d.romanick at intel.com>
> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=59833
> ---
>   tests/glx/glx-swap-pixmap.c | 16 ++++++++++++++--
>   1 file changed, 14 insertions(+), 2 deletions(-)
>
> diff --git a/tests/glx/glx-swap-pixmap.c b/tests/glx/glx-swap-pixmap.c
> index 1a91578..855396a 100644
> --- a/tests/glx/glx-swap-pixmap.c
> +++ b/tests/glx/glx-swap-pixmap.c
> @@ -44,9 +44,11 @@ main(int argc, char **argv)
>   {
>   	Pixmap p;
>   	GLXPixmap g;
> -	float green[4] = {0.0, 1.0, 0.0, 0.0};
> +	static const float green_alpha_zero[4] = {0.0, 1.0, 0.0, 0.0};
> +	static const float green_alpha_one[4] = {0.0, 1.0, 0.0, 1.0};
>   	GLXContext ctx;
>   	bool pass;
> +	GLint alpha_bits;
>
>   	dpy = XOpenDisplay(NULL);
>   	if (dpy == NULL) {
> @@ -80,7 +82,17 @@ main(int argc, char **argv)
>   	 */
>   	XSync(dpy, False);
>
> -	pass = piglit_probe_rect_rgba(0, 0, piglit_width, piglit_height, green);
> +	/* If the visual has no alpha, then the GL spec requires that 1.0 be
> +	 * read back.  Otherwise, we should read back the 0.0 that we wrote.
> +	 */
> +	glGetIntegerv(GL_ALPHA_BITS,&alpha_bits);
> +	if (alpha_bits == 0) {
> +		pass = piglit_probe_rect_rgba(0, 0, piglit_width, piglit_height,
> +					      green_alpha_one);
> +	} else {
> +		pass = piglit_probe_rect_rgba(0, 0, piglit_width, piglit_height,
> +					      green_alpha_zero);
> +	}
>
>   	glXDestroyPixmap(dpy, g);
>

Reviewed-by: Brian Paul <brianp at vmware.com>