summaryrefslogtreecommitdiffstats
path: root/src/video_core/shader/shader.h
blob: 38ea717ab62f5f43e28fb5b003e96dbcd567c57d (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
// Copyright 2015 Citra Emulator Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.

#pragma once

#include <array>
#include <cstddef>
#include <type_traits>
#include <nihstro/shader_bytecode.h>
#include "common/assert.h"
#include "common/common_funcs.h"
#include "common/common_types.h"
#include "common/vector_math.h"
#include "video_core/pica_types.h"
#include "video_core/regs_rasterizer.h"
#include "video_core/regs_shader.h"

using nihstro::RegisterType;
using nihstro::SourceRegister;
using nihstro::DestRegister;

namespace Pica {

namespace Shader {

struct AttributeBuffer {
    alignas(16) Math::Vec4<float24> attr[16];
};

struct OutputVertex {
    Math::Vec4<float24> pos;
    Math::Vec4<float24> quat;
    Math::Vec4<float24> color;
    Math::Vec2<float24> tc0;
    Math::Vec2<float24> tc1;
    float24 tc0_w;
    INSERT_PADDING_WORDS(1);
    Math::Vec3<float24> view;
    INSERT_PADDING_WORDS(1);
    Math::Vec2<float24> tc2;

    static OutputVertex FromAttributeBuffer(const RasterizerRegs& regs, AttributeBuffer& output);
};
#define ASSERT_POS(var, pos)                                                                       \
    static_assert(offsetof(OutputVertex, var) == pos * sizeof(float24), "Semantic at wrong "       \
                                                                        "offset.")
ASSERT_POS(pos, RasterizerRegs::VSOutputAttributes::POSITION_X);
ASSERT_POS(quat, RasterizerRegs::VSOutputAttributes::QUATERNION_X);
ASSERT_POS(color, RasterizerRegs::VSOutputAttributes::COLOR_R);
ASSERT_POS(tc0, RasterizerRegs::VSOutputAttributes::TEXCOORD0_U);
ASSERT_POS(tc1, RasterizerRegs::VSOutputAttributes::TEXCOORD1_U);
ASSERT_POS(tc0_w, RasterizerRegs::VSOutputAttributes::TEXCOORD0_W);
ASSERT_POS(view, RasterizerRegs::VSOutputAttributes::VIEW_X);
ASSERT_POS(tc2, RasterizerRegs::VSOutputAttributes::TEXCOORD2_U);
#undef ASSERT_POS
static_assert(std::is_pod<OutputVertex>::value, "Structure is not POD");
static_assert(sizeof(OutputVertex) == 24 * sizeof(float), "OutputVertex has invalid size");

/**
 * This structure contains the state information that needs to be unique for a shader unit. The 3DS
 * has four shader units that process shaders in parallel. At the present, Citra only implements a
 * single shader unit that processes all shaders serially. Putting the state information in a struct
 * here will make it easier for us to parallelize the shader processing later.
 */
struct UnitState {
    struct Registers {
        // The registers are accessed by the shader JIT using SSE instructions, and are therefore
        // required to be 16-byte aligned.
        alignas(16) Math::Vec4<float24> input[16];
        alignas(16) Math::Vec4<float24> temporary[16];
        alignas(16) Math::Vec4<float24> output[16];
    } registers;
    static_assert(std::is_pod<Registers>::value, "Structure is not POD");

    bool conditional_code[2];

    // Two Address registers and one loop counter
    // TODO: How many bits do these actually have?
    s32 address_registers[3];

    static size_t InputOffset(const SourceRegister& reg) {
        switch (reg.GetRegisterType()) {
        case RegisterType::Input:
            return offsetof(UnitState, registers.input) +
                   reg.GetIndex() * sizeof(Math::Vec4<float24>);

        case RegisterType::Temporary:
            return offsetof(UnitState, registers.temporary) +
                   reg.GetIndex() * sizeof(Math::Vec4<float24>);

        default:
            UNREACHABLE();
            return 0;
        }
    }

    static size_t OutputOffset(const DestRegister& reg) {
        switch (reg.GetRegisterType()) {
        case RegisterType::Output:
            return offsetof(UnitState, registers.output) +
                   reg.GetIndex() * sizeof(Math::Vec4<float24>);

        case RegisterType::Temporary:
            return offsetof(UnitState, registers.temporary) +
                   reg.GetIndex() * sizeof(Math::Vec4<float24>);

        default:
            UNREACHABLE();
            return 0;
        }
    }

    /**
     * Loads the unit state with an input vertex.
     *
     * @param config Shader configuration registers corresponding to the unit.
     * @param input Attribute buffer to load into the input registers.
     */
    void LoadInput(const ShaderRegs& config, const AttributeBuffer& input);

    void WriteOutput(const ShaderRegs& config, AttributeBuffer& output);
};

struct ShaderSetup {
    struct {
        // The float uniforms are accessed by the shader JIT using SSE instructions, and are
        // therefore required to be 16-byte aligned.
        alignas(16) Math::Vec4<float24> f[96];

        std::array<bool, 16> b;
        std::array<Math::Vec4<u8>, 4> i;
    } uniforms;

    static size_t GetFloatUniformOffset(unsigned index) {
        return offsetof(ShaderSetup, uniforms.f) + index * sizeof(Math::Vec4<float24>);
    }

    static size_t GetBoolUniformOffset(unsigned index) {
        return offsetof(ShaderSetup, uniforms.b) + index * sizeof(bool);
    }

    static size_t GetIntUniformOffset(unsigned index) {
        return offsetof(ShaderSetup, uniforms.i) + index * sizeof(Math::Vec4<u8>);
    }

    std::array<u32, 1024> program_code;
    std::array<u32, 1024> swizzle_data;

    /// Data private to ShaderEngines
    struct EngineData {
        unsigned int entry_point;
        /// Used by the JIT, points to a compiled shader object.
        const void* cached_shader = nullptr;
    } engine_data;
};

class ShaderEngine {
public:
    virtual ~ShaderEngine() = default;

    /**
     * Performs any shader unit setup that only needs to happen once per shader (as opposed to once
     * per vertex, which would happen within the `Run` function).
     */
    virtual void SetupBatch(ShaderSetup& setup, unsigned int entry_point) = 0;

    /**
     * Runs the currently setup shader.
     *
     * @param setup Shader engine state, must be setup with SetupBatch on each shader change.
     * @param state Shader unit state, must be setup with input data before each shader invocation.
     */
    virtual void Run(const ShaderSetup& setup, UnitState& state) const = 0;
};

// TODO(yuriks): Remove and make it non-global state somewhere
ShaderEngine* GetEngine();
void Shutdown();

} // namespace Shader

} // namespace Pica