[Mesa-dev] [PATCH 2/2] mesa: Moves up error check for subtexture dimensions

[Eduardo Lima Mitev]

On 09/15/2015 09:23 PM, Jason Ekstrand wrote:
> On Tue, Sep 15, 2015 at 4:47 AM, Eduardo Lima Mitev <elima at igalia.com> wrote:
>> For consistency and efficiency, the (sub)texture dimension error check
>> should go before the validation of format, type and internal format.
> 
> You mentioned in another patch that this fixes a bug or, at the very
> least, prevents one.  What bug is that?  I ask because my personal
> inclination would be to keep them in the order they were before.
> --Jason
> 

These tests fail without this patch, because they fail the validation of
format+type+internalFormat (INVALID_OPERATION) which happens before the
check for texture dimensions (INVALID_VALUE, the expected error).

dEQP-GLES2.functional.negative_api.texture.texsubimage2d_neg_offset
dEQP-GLES2.functional.negative_api.texture.texsubimage2d_offset_allowed
dEQP-GLES2.functional.negative_api.texture.texsubimage2d_neg_wdt_hgt

In all 3, the failing combination is:

format = GL_RGB, type = GL_UNSIGNED_BYTE, internalFormat = GL_RGBA

Following the spec, the effective internal format should be GL_RGB8 (per
table 3.12, page 128 of OpenGL-ES 3.0.4). So, it is actually failing the
double-check I added in the previous patch, in which I obtain again the
base format from the effective internal format to compare it with the
original internal format in base form passed to the function. So GL_RGB8
-> GL_RGB which != GL_RGBA.

Now I'm puzzled. Is the combination above valid? As I interpret the
spec, it isn't. Which means the tests would be wrong, but that's strange
too.

>> ---
>>  src/mesa/main/teximage.c | 12 ++++++------
>>  1 file changed, 6 insertions(+), 6 deletions(-)
>>
>> diff --git a/src/mesa/main/teximage.c b/src/mesa/main/teximage.c
>> index d9453e3..09040d5 100644
>> --- a/src/mesa/main/teximage.c
>> +++ b/src/mesa/main/teximage.c
>> @@ -2117,6 +2117,12 @@ texsubimage_error_check(struct gl_context *ctx, GLuint dimensions,
>>        return GL_TRUE;
>>     }
>>
>> +   if (error_check_subtexture_dimensions(ctx, dimensions,
>> +                                         texImage, xoffset, yoffset, zoffset,
>> +                                         width, height, depth, callerName)) {
>> +      return GL_TRUE;
>> +   }
>> +
>>     err = _mesa_error_check_format_and_type(ctx, format, type);
>>     if (err != GL_NO_ERROR) {
>>        _mesa_error(ctx, err,
>> @@ -2145,12 +2151,6 @@ texsubimage_error_check(struct gl_context *ctx, GLuint dimensions,
>>        return GL_TRUE;
>>     }
>>
>> -   if (error_check_subtexture_dimensions(ctx, dimensions,
>> -                                         texImage, xoffset, yoffset, zoffset,
>> -                                         width, height, depth, callerName)) {
>> -      return GL_TRUE;
>> -   }
>> -
>>     if (_mesa_is_format_compressed(texImage->TexFormat)) {
>>        if (_mesa_format_no_online_compression(ctx, texImage->InternalFormat)) {
>>           _mesa_error(ctx, GL_INVALID_OPERATION,
>> --
>> 2.4.6
>>
>