[Piglit] [RFC 1/3] framework: introduce interface for external buffers

[Chad Versace]

On 03/01/2013 10:57 AM, Chad Versace wrote:
> On 02/26/2013 05:15 AM, Topi Pohjolainen wrote:
>> In order to test the OES_EGL_image_external with planar formats such
>> as YUV420 or NV12, one needs a way for creating buffers that can be
>> passed to EGL and filling them with YUV-data for the GL-stack to
>> sample.
>> By the nature the extension in question deals with platform specific
>> buffers and hence the idea here is to push the details down into the
>> platform specific logic leaving the tests themselves platform
>> independent.
>>
>> Signed-off-by: Topi Pohjolainen <topi.pohjolainen at intel.com>
>> ---
>>  tests/util/piglit-framework-gl.c                   |   29 ++++++++++++++++++++
>>  tests/util/piglit-framework-gl.h                   |   21 ++++++++++++++
>>  .../util/piglit-framework-gl/piglit_gl_framework.h |   23 ++++++++++++++++
>>  3 files changed, 73 insertions(+)


>> +void *
>> +piglit_create_ext_420_buf(unsigned w, unsigned h, bool swap_vu,
>> +			const void *y, const void *u, const void *v)
>> +{
>> +	if (!gl_fw->create_external_420_buffer)
>> +		return NULL;
>> +
>> +	return gl_fw->create_external_420_buffer(gl_fw, w, h, swap_vu, y, u, v);
>> +}
> 
> Later, in patch 3, you write the test so that, if piglit_create_ext_420_buf()
> fails then the test reports PIGLIT_FAIL. But the convention in piglit is to report
> PIGLIT_SKIP when the platform is incapable of running the test.
> 
> There are two choices to handle this:
>   1. Here, in piglit_create_ext_420_buf(), report PIGLIT_SKIP if it fails
>      to create the buffer.
> 
>   2. In the testfile itself, report PIGLIT_SKIP if piglit_create_ext_420()
>      fails.


My opinion here has changed after I thought about it more. I think that the
piglit_gbm_framework_create() should set gl_fw->create_external_420_buffer
only if the platform is capable of creating a yuv420 buffer.

If a test calls piglit_create_ext_420_buf(), but the function is unable to create
the buffer because the platform doesn't support it (that is, because
gl_fw->create_external_420_buffer is NULL), then the test should report PIGLIT_SKIP.
That is the convention in piglit; if a test attempts to test something that the
platform is incapable of doing, then it reports PIGLIT_SKIP. In this case,
the best place to report PIGLIT_SKIP is here inside piglit_create_ext_420_buf().