SPIRV-Cross/tests-other/msl_ycbcr_conversion_test.cpp
Chip Davis 39dce88d3b MSL: Add support for sampler Y'CbCr conversion.
This change introduces functions and in one case, a class, to support
the `VK_KHR_sampler_ycbcr_conversion` extension. Except in the case of
GBGR8 and BGRG8 formats, for which Metal natively supports implicit
chroma reconstruction, we're on our own here. We have to do everything
ourselves. Much of the complexity comes from the need to support
multiple planes, which must now be passed to functions that use the
corresponding combined image-samplers. The rest is from the actual
Y'CbCr conversion itself, which requires additional post-processing of
the sample retrieved from the image.

Passing sampled images to a function was a particular problem. To
support this, I've added a new class which is emitted to MSL shaders
that pass sampled images with Y'CbCr conversions attached around. It
can handle sampled images with or without Y'CbCr conversion. This is an
awful abomination that should not exist, but I'm worried that there's
some shader out there which does this. This support requires Metal 2.0
to work properly, because it uses default-constructed texture objects,
which were only added in MSL 2. I'm not even going to get into arrays of
combined image-samplers--that's a whole other can of worms.  They are
deliberately unsupported in this change.

I've taken the liberty of refactoring the support for texture swizzling
while I'm at it. It's now treated as a post-processing step similar to
Y'CbCr conversion. I'd like to think this is cleaner than having
everything in `to_function_name()`/`to_function_args()`. It still looks
really hairy, though. I did, however, get rid of the explicit type
arguments to `spvGatherSwizzle()`/`spvGatherCompareSwizzle()`.

Update the C API. In addition to supporting this new functionality, add
some compiler options that I added in previous changes, but for which I
neglected to update the C API.
2019-09-01 18:35:53 -05:00

104 lines
2.9 KiB
C++

// Testbench for MSL constexpr samplers, with Y'CbCr conversion.
// It does not validate output, but it's useful for ad-hoc testing.
#ifdef _MSC_VER
#define _CRT_SECURE_NO_WARNINGS
#endif
#include <spirv_cross_c.h>
#include <stdlib.h>
#include <stdio.h>
#include <vector>
#define SPVC_CHECKED_CALL(x) do { \
if ((x) != SPVC_SUCCESS) { \
fprintf(stderr, "Failed at line %d.\n", __LINE__); \
exit(1); \
} \
} while(0)
#define SPVC_CHECKED_CALL_NEGATIVE(x) do { \
g_fail_on_error = SPVC_FALSE; \
if ((x) == SPVC_SUCCESS) { \
fprintf(stderr, "Failed at line %d.\n", __LINE__); \
exit(1); \
} \
g_fail_on_error = SPVC_TRUE; \
} while(0)
static std::vector<SpvId> read_file(const char *path)
{
long len;
FILE *file = fopen(path, "rb");
if (!file)
return {};
fseek(file, 0, SEEK_END);
len = ftell(file);
rewind(file);
std::vector<SpvId> buffer(len / sizeof(SpvId));
if (fread(buffer.data(), 1, len, file) != (size_t)len)
{
fclose(file);
return {};
}
fclose(file);
return buffer;
}
int main(int argc, char **argv)
{
if (argc != 2)
return EXIT_FAILURE;
auto buffer = read_file(argv[1]);
if (buffer.empty())
return EXIT_FAILURE;
spvc_context ctx;
spvc_parsed_ir parsed_ir;
spvc_compiler compiler;
spvc_compiler_options options;
SPVC_CHECKED_CALL(spvc_context_create(&ctx));
SPVC_CHECKED_CALL(spvc_context_parse_spirv(ctx, buffer.data(), buffer.size(), &parsed_ir));
SPVC_CHECKED_CALL(spvc_context_create_compiler(ctx, SPVC_BACKEND_MSL, parsed_ir, SPVC_CAPTURE_MODE_TAKE_OWNERSHIP, &compiler));
SPVC_CHECKED_CALL(spvc_compiler_create_compiler_options(compiler, &options));
SPVC_CHECKED_CALL(spvc_compiler_options_set_uint(options, SPVC_COMPILER_OPTION_MSL_VERSION, SPVC_MAKE_MSL_VERSION(2, 0, 0)));
SPVC_CHECKED_CALL(spvc_compiler_install_compiler_options(compiler, options));
spvc_msl_resource_binding binding;
spvc_msl_resource_binding_init(&binding);
binding.desc_set = 1;
binding.binding = 2;
binding.stage = SpvExecutionModelFragment;
binding.msl_texture = 0;
binding.msl_sampler = 0;
SPVC_CHECKED_CALL(spvc_compiler_msl_add_resource_binding(compiler, &binding));
spvc_msl_constexpr_sampler samp;
spvc_msl_sampler_ycbcr_conversion conv;
spvc_msl_constexpr_sampler_init(&samp);
spvc_msl_sampler_ycbcr_conversion_init(&conv);
conv.planes = 3;
conv.resolution = SPVC_MSL_FORMAT_RESOLUTION_422;
conv.chroma_filter = SPVC_MSL_SAMPLER_FILTER_LINEAR;
conv.x_chroma_offset = SPVC_MSL_CHROMA_LOCATION_MIDPOINT;
conv.ycbcr_model = SPVC_MSL_SAMPLER_YCBCR_MODEL_CONVERSION_YCBCR_BT_2020;
conv.ycbcr_range = SPVC_MSL_SAMPLER_YCBCR_RANGE_ITU_NARROW;
conv.bpc = 8;
SPVC_CHECKED_CALL(spvc_compiler_msl_remap_constexpr_sampler_by_binding_ycbcr(compiler, 1, 2, &samp, &conv));
const char *str;
SPVC_CHECKED_CALL(spvc_compiler_compile(compiler, &str));
// Should be marked, as a sanity check.
if (!spvc_compiler_msl_is_resource_used(compiler, SpvExecutionModelFragment, 1, 2))
return EXIT_FAILURE;
fprintf(stderr, "Output:\n%s\n", str);
}