[Mesa-dev] [PATCH 07/14] mesa: Create the default (name==0) buffer texture.

[Kenneth Graunke]

On 03/28/2012 10:58 AM, Eric Anholt wrote:
> All that should be needed is that it exists.  Fixes segfaults on first
> _mesa_update_context() with a samplerBuffer-using shader active but
> without a particular buffer texture enabled.
> ---
>   src/glsl/builtins/tools/texture_builtins.py |    4 +---
>   src/mesa/main/texobj.c                      |    5 +++++
>   2 files changed, 6 insertions(+), 3 deletions(-)
>
> diff --git a/src/glsl/builtins/tools/texture_builtins.py b/src/glsl/builtins/tools/texture_builtins.py
> index 3a4943a..bbbbd0b 100755
> --- a/src/glsl/builtins/tools/texture_builtins.py
> +++ b/src/glsl/builtins/tools/texture_builtins.py
> @@ -73,9 +73,7 @@ def generate_sigs(g, tex_inst, sampler_type, variant = 0, unused_fields = 0):
>           print "\n       (declare (in) " + vec_type("i" if tex_inst == "txf" else "", coord_dim + extra_dim) + " P)",
>       if tex_inst == "txl":
>           print "\n       (declare (in) float lod)",
> -    elif (tex_inst == "txf" and "Buffer" not in sampler_type):
> -        print "\n       (declare (in) int lod)",
> -    elif (tex_inst == "txs" and "Rect" not in sampler_type):
> +    elif ((tex_inst == "txf" or tex_inst == "txs") and "Buffer" not in sampler_type and "Rect" not in sampler_type):
>           print "\n       (declare (in) int lod)",
>       elif tex_inst == "txd":
>           grad_type = vec_type("", coord_dim)

You meant to squash this into patch 6, not this one.  I'm fine with the 
change.

> diff --git a/src/mesa/main/texobj.c b/src/mesa/main/texobj.c
> index d7dee4f..88dc3b1 100644
> --- a/src/mesa/main/texobj.c
> +++ b/src/mesa/main/texobj.c
> @@ -756,6 +756,9 @@ _mesa_get_fallback_texture(struct gl_context *ctx, gl_texture_index tex)
>            target = GL_TEXTURE_1D;
>            break;
>         case TEXTURE_BUFFER_INDEX:
> +         dims = 0;
> +         target = GL_TEXTURE_BUFFER;
> +         break;
>         case TEXTURE_EXTERNAL_INDEX:
>         default:
>            /* no-op */
> @@ -794,6 +797,8 @@ _mesa_get_fallback_texture(struct gl_context *ctx, gl_texture_index tex)
>                                       GL_RGBA, texFormat);
>
>            switch (dims) {
> +	 case 0:
> +	    break;
>            case 1:
>               ctx->Driver.TexImage1D(ctx, texImage, GL_RGBA,
>                                      width, 0,