Files
Xenia-Canary/src/xenia/gpu/shaders/apply_gamma_pwl.xesli
2022-06-24 23:24:30 +03:00

108 lines
4.4 KiB
Plaintext

/**
******************************************************************************
* Xenia : Xbox 360 Emulator Research Project *
******************************************************************************
* Copyright 2022 Ben Vanik. All rights reserved. *
* Released under the BSD license - see LICENSE in the root for more details. *
******************************************************************************
*/
#include "../../ui/shaders/xesl.xesli"
float XeApplyPWLGamma(uint input_value, xesl_uint2 ramp_value) {
// output = base + (multiplier * delta) / increment
// https://developer.amd.com/wordpress/media/2012/10/RRG-216M56-03oOEM.pdf
// The lower 6 bits of the base and the delta are 0 (though enforcing that in
// the shader is not necessary).
// The `(multiplier * delta) / increment` part may result in a nonzero value
// in the lower 6 bits of the result, however, so doing `* (1.0f / 64.0f)`
// instead of `>> 6` to preserve them (if the render target is 16bpc rather
// than 10bpc, for instance).
return xesl_saturate(
(float(ramp_value.x) +
float((input_value & 7u) * ramp_value.y) * (1.0 / 8.0)) *
(1.0 / (64.0 * 1023.0)));
}
#ifdef XE_APPLY_GAMMA_COMPUTE
#ifdef XE_APPLY_GAMMA_FXAA_LUMA
#define XE_APPLY_GAMMA_DEST_FORMAT xesl_imageFormat_rgba16f
#else
#define XE_APPLY_GAMMA_DEST_FORMAT xesl_imageFormat_rgb10_a2
#endif
xesl_pushConstants_begin(b0, space0)
xesl_uint2 xe_apply_gamma_size;
xesl_pushConstants_end
#define xesl_localSize_x 16
#define xesl_localSize_y 8
#define xesl_localSize_z 1
xesl_entry_bindings_begin_compute
xesl_pushConstants_binding(buffer(0))
xesl_entry_binding_next
xesl_texture(xesl_utextureBuffer, xe_apply_gamma_ramp, set=0, binding=0, t0,
space0, texture(0))
xesl_entry_binding_next
xesl_texture(xesl_texture2D, xe_apply_gamma_source, set=1, binding=0, t1,
space0, texture(1))
xesl_entry_binding_next
xesl_writeImage(xesl_image2D, XE_APPLY_GAMMA_DEST_FORMAT, xe_apply_gamma_dest,
set=2, binding=0, u0, space0, texture(2))
xesl_entry_bindings_end_inputs_begin_compute
xesl_entry_input_globalInvocationID
xesl_entry_inputs_end_code_begin_compute
xesl_uint2 pixel_index = xesl_GlobalInvocationID.xy;
xesl_dont_flatten
if (any(xesl_greaterThanEqual(pixel_index,
xesl_pushConstant(xe_apply_gamma_size)))) {
return;
}
#else
xesl_entry_outputs_begin
xesl_entry_output_target(xesl_float4, xe_apply_gamma_dest, 0)
xesl_entry_outputs_end_stageInputs_begin
xesl_entry_stageInputs_end_bindings_begin_pixel
xesl_texture(xesl_utextureBuffer, xe_apply_gamma_ramp, set=0, binding=0, t0,
space0, texture(0))
xesl_entry_binding_next
xesl_texture(xesl_texture2D, xe_apply_gamma_source, set=1, binding=0, t1,
space0, texture(1))
xesl_entry_bindings_end_inputs_begin
xesl_entry_input_fragCoord
xesl_entry_inputs_end_code_begin
xesl_uint2 pixel_index = xesl_uint2(xesl_FragCoord.xy);
#endif // XE_APPLY_GAMMA_COMPUTE
// UNORM conversion according to the Direct3D 10+ rules.
xesl_uint3 apply_gamma_input = xesl_uint3(
xesl_texelFetch2D(xe_apply_gamma_source, pixel_index, 0).rgb * 1023.0 +
0.5);
// TODO(Triang3l): If this is ever used for gamma other than 128 entries for a
// 10bpc front buffer, handle the increment from DC_LUTA/B_CONTROL. Currently
// assuming it's 2^3 = 8, or 1024 / 128.
xesl_float4 apply_gamma_output;
apply_gamma_output.r = XeApplyPWLGamma(
apply_gamma_input.r,
xesl_texelFetchBuffer(xe_apply_gamma_ramp,
(apply_gamma_input.r >> 3u) * 3u).rg);
apply_gamma_output.g = XeApplyPWLGamma(
apply_gamma_input.g,
xesl_texelFetchBuffer(xe_apply_gamma_ramp,
(apply_gamma_input.g >> 3u) * 3u + 1u).rg);
apply_gamma_output.b = XeApplyPWLGamma(
apply_gamma_input.b,
xesl_texelFetchBuffer(xe_apply_gamma_ramp,
(apply_gamma_input.b >> 3u) * 3u + 2u).rg);
#ifdef XE_APPLY_GAMMA_FXAA_LUMA
// Perceptual luma.
apply_gamma_output.a =
dot(apply_gamma_output.rgb, xesl_float3(0.299, 0.587, 0.114));
#else
apply_gamma_output.a = 1.0;
#endif
#ifdef XE_APPLY_GAMMA_COMPUTE
xesl_imageStore2DRGBA(xe_apply_gamma_dest, pixel_index, apply_gamma_output);
xesl_entry_code_end_compute
#else
xesl_Output(xe_apply_gamma_dest) = apply_gamma_output;
xesl_entry_code_end
#endif