// SPDX-FileCopyrightText: Copyright 2021 yuzu Emulator Project
// SPDX-License-Identifier: GPL-2.0-or-later
#include <algorithm>
#include <array>
#include <vector>
#include "common/alignment.h"
#include "common/assert.h"
#include "shader_recompiler/shader_info.h"
#include "video_core/transform_feedback.h"
namespace VideoCommon {
std::vector<Shader::TransformFeedbackVarying> MakeTransformFeedbackVaryings(
const TransformFeedbackState& state) {
static constexpr std::array VECTORS{
28, // gl_Position
32, // Generic 0
36, // Generic 1
40, // Generic 2
44, // Generic 3
48, // Generic 4
52, // Generic 5
56, // Generic 6
60, // Generic 7
64, // Generic 8
68, // Generic 9
72, // Generic 10
76, // Generic 11
80, // Generic 12
84, // Generic 13
88, // Generic 14
92, // Generic 15
96, // Generic 16
100, // Generic 17
104, // Generic 18
108, // Generic 19
112, // Generic 20
116, // Generic 21
120, // Generic 22
124, // Generic 23
128, // Generic 24
132, // Generic 25
136, // Generic 26
140, // Generic 27
144, // Generic 28
148, // Generic 29
152, // Generic 30
156, // Generic 31
160, // gl_FrontColor
164, // gl_FrontSecondaryColor
160, // gl_BackColor
164, // gl_BackSecondaryColor
192, // gl_TexCoord[0]
196, // gl_TexCoord[1]
200, // gl_TexCoord[2]
204, // gl_TexCoord[3]
208, // gl_TexCoord[4]
212, // gl_TexCoord[5]
216, // gl_TexCoord[6]
220, // gl_TexCoord[7]
};
std::vector<Shader::TransformFeedbackVarying> xfb(256);
for (size_t buffer = 0; buffer < state.layouts.size(); ++buffer) {
const auto& locations = state.varyings[buffer];
const auto& layout = state.layouts[buffer];
const u32 varying_count = layout.varying_count;
u32 highest = 0;
for (u32 offset = 0; offset < varying_count; ++offset) {
const u32 base_offset = offset;
const u8 location = locations[offset];
UNIMPLEMENTED_IF_MSG(layout.stream != 0, "Stream is not zero: {}", layout.stream);
Shader::TransformFeedbackVarying varying{
.buffer = static_cast<u32>(buffer),
.stride = layout.stride,
.offset = offset * 4,
.components = 1,
};
if (std::ranges::find(VECTORS, Common::AlignDown(location, 4)) != VECTORS.end()) {
UNIMPLEMENTED_IF_MSG(location % 4 != 0, "Unaligned TFB");
const u8 base_index = location / 4;
while (offset + 1 < varying_count && base_index == locations[offset + 1] / 4) {
++offset;
++varying.components;
}
}
xfb[location] = varying;
highest = std::max(highest, (base_offset + varying.components) * 4);
}
UNIMPLEMENTED_IF(highest != layout.stride);
}
return xfb;
}
} // namespace VideoCommon
