piet-gpu/shader/gen/transform_leaf.msl

#pragma clang diagnostic ignored "-Wmissing-prototypes"
#pragma clang diagnostic ignored "-Wmissing-braces"

#include <metal_stdlib>
#include <simd/simd.h>

using namespace metal;

template<typename T, size_t Num>
struct spvUnsafeArray
{
    T elements[Num ? Num : 1];
    
    thread T& operator [] (size_t pos) thread
    {
        return elements[pos];
    }
    constexpr const thread T& operator [] (size_t pos) const thread
    {
        return elements[pos];
    }
    
    device T& operator [] (size_t pos) device
    {
        return elements[pos];
    }
    constexpr const device T& operator [] (size_t pos) const device
    {
        return elements[pos];
    }
    
    constexpr const constant T& operator [] (size_t pos) const constant
    {
        return elements[pos];
    }
    
    threadgroup T& operator [] (size_t pos) threadgroup
    {
        return elements[pos];
    }
    constexpr const threadgroup T& operator [] (size_t pos) const threadgroup
    {
        return elements[pos];
    }
};

struct Alloc
{
    uint offset;
};

struct TransformRef
{
    uint offset;
};

struct Transform
{
    float4 mat;
    float2 translate;
};

struct TransformSegRef
{
    uint offset;
};

struct TransformSeg
{
    float4 mat;
    float2 translate;
};

struct Memory
{
    uint mem_offset;
    uint mem_error;
    uint memory[1];
};

struct SceneBuf
{
    uint scene[1];
};

struct Alloc_1
{
    uint offset;
};

struct Config
{
    uint n_elements;
    uint n_pathseg;
    uint width_in_tiles;
    uint height_in_tiles;
    Alloc_1 tile_alloc;
    Alloc_1 bin_alloc;
    Alloc_1 ptcl_alloc;
    Alloc_1 pathseg_alloc;
    Alloc_1 anno_alloc;
    Alloc_1 trans_alloc;
    Alloc_1 path_bbox_alloc;
    Alloc_1 drawmonoid_alloc;
    Alloc_1 clip_alloc;
    Alloc_1 clip_bic_alloc;
    Alloc_1 clip_stack_alloc;
    Alloc_1 clip_bbox_alloc;
    Alloc_1 draw_bbox_alloc;
    Alloc_1 drawinfo_alloc;
    uint n_trans;
    uint n_path;
    uint n_clip;
    uint trans_offset;
    uint linewidth_offset;
    uint pathtag_offset;
    uint pathseg_offset;
    uint drawtag_offset;
    uint drawdata_offset;
};

struct ConfigBuf
{
    Config conf;
};

struct Transform_1
{
    float4 mat;
    float2 translate;
    char _m0_final_padding[8];
};

struct ParentBuf
{
    Transform_1 parent[1];
};

constant uint3 gl_WorkGroupSize [[maybe_unused]] = uint3(256u, 1u, 1u);

static inline __attribute__((always_inline))
Transform Transform_read(thread const TransformRef& ref, const device SceneBuf& v_96)
{
    uint ix = ref.offset >> uint(2);
    uint raw0 = v_96.scene[ix + 0u];
    uint raw1 = v_96.scene[ix + 1u];
    uint raw2 = v_96.scene[ix + 2u];
    uint raw3 = v_96.scene[ix + 3u];
    uint raw4 = v_96.scene[ix + 4u];
    uint raw5 = v_96.scene[ix + 5u];
    Transform s;
    s.mat = float4(as_type<float>(raw0), as_type<float>(raw1), as_type<float>(raw2), as_type<float>(raw3));
    s.translate = float2(as_type<float>(raw4), as_type<float>(raw5));
    return s;
}

static inline __attribute__((always_inline))
TransformRef Transform_index(thread const TransformRef& ref, thread const uint& index)
{
    return TransformRef{ ref.offset + (index * 24u) };
}

static inline __attribute__((always_inline))
Transform combine_monoid(thread const Transform& a, thread const Transform& b)
{
    Transform c;
    c.mat = (a.mat.xyxy * b.mat.xxzz) + (a.mat.zwzw * b.mat.yyww);
    c.translate = ((a.mat.xy * b.translate.x) + (a.mat.zw * b.translate.y)) + a.translate;
    return c;
}

static inline __attribute__((always_inline))
Transform monoid_identity()
{
    return Transform{ float4(1.0, 0.0, 0.0, 1.0), float2(0.0) };
}

static inline __attribute__((always_inline))
bool touch_mem(thread const Alloc& alloc, thread const uint& offset)
{
    return true;
}

static inline __attribute__((always_inline))
void write_mem(thread const Alloc& alloc, thread const uint& offset, thread const uint& val, device Memory& v_71)
{
    Alloc param = alloc;
    uint param_1 = offset;
    if (!touch_mem(param, param_1))
    {
        return;
    }
    v_71.memory[offset] = val;
}

static inline __attribute__((always_inline))
void TransformSeg_write(thread const Alloc& a, thread const TransformSegRef& ref, thread const TransformSeg& s, device Memory& v_71)
{
    uint ix = ref.offset >> uint(2);
    Alloc param = a;
    uint param_1 = ix + 0u;
    uint param_2 = as_type<uint>(s.mat.x);
    write_mem(param, param_1, param_2, v_71);
    Alloc param_3 = a;
    uint param_4 = ix + 1u;
    uint param_5 = as_type<uint>(s.mat.y);
    write_mem(param_3, param_4, param_5, v_71);
    Alloc param_6 = a;
    uint param_7 = ix + 2u;
    uint param_8 = as_type<uint>(s.mat.z);
    write_mem(param_6, param_7, param_8, v_71);
    Alloc param_9 = a;
    uint param_10 = ix + 3u;
    uint param_11 = as_type<uint>(s.mat.w);
    write_mem(param_9, param_10, param_11, v_71);
    Alloc param_12 = a;
    uint param_13 = ix + 4u;
    uint param_14 = as_type<uint>(s.translate.x);
    write_mem(param_12, param_13, param_14, v_71);
    Alloc param_15 = a;
    uint param_16 = ix + 5u;
    uint param_17 = as_type<uint>(s.translate.y);
    write_mem(param_15, param_16, param_17, v_71);
}

kernel void main0(device Memory& v_71 [[buffer(0)]], const device ConfigBuf& _278 [[buffer(1)]], const device SceneBuf& v_96 [[buffer(2)]], const device ParentBuf& _376 [[buffer(3)]], uint3 gl_GlobalInvocationID [[thread_position_in_grid]], uint3 gl_LocalInvocationID [[thread_position_in_threadgroup]], uint3 gl_WorkGroupID [[threadgroup_position_in_grid]])
{
    threadgroup Transform sh_scratch[256];
    uint ix = gl_GlobalInvocationID.x * 8u;
    TransformRef ref = TransformRef{ _278.conf.trans_offset + (ix * 24u) };
    TransformRef param = ref;
    Transform agg = Transform_read(param, v_96);
    spvUnsafeArray<Transform, 8> local;
    local[0] = agg;
    for (uint i = 1u; i < 8u; i++)
    {
        TransformRef param_1 = ref;
        uint param_2 = i;
        TransformRef param_3 = Transform_index(param_1, param_2);
        Transform param_4 = agg;
        Transform param_5 = Transform_read(param_3, v_96);
        agg = combine_monoid(param_4, param_5);
        local[i] = agg;
    }
    sh_scratch[gl_LocalInvocationID.x] = agg;
    for (uint i_1 = 0u; i_1 < 8u; i_1++)
    {
        threadgroup_barrier(mem_flags::mem_threadgroup);
        if (gl_LocalInvocationID.x >= (1u << i_1))
        {
            Transform other = sh_scratch[gl_LocalInvocationID.x - (1u << i_1)];
            Transform param_6 = other;
            Transform param_7 = agg;
            agg = combine_monoid(param_6, param_7);
        }
        threadgroup_barrier(mem_flags::mem_threadgroup);
        sh_scratch[gl_LocalInvocationID.x] = agg;
    }
    threadgroup_barrier(mem_flags::mem_threadgroup);
    Transform row = monoid_identity();
    if (gl_WorkGroupID.x > 0u)
    {
        uint _379 = gl_WorkGroupID.x - 1u;
        row.mat = _376.parent[_379].mat;
        row.translate = _376.parent[_379].translate;
    }
    if (gl_LocalInvocationID.x > 0u)
    {
        Transform param_8 = row;
        Transform param_9 = sh_scratch[gl_LocalInvocationID.x - 1u];
        row = combine_monoid(param_8, param_9);
    }
    Alloc param_12;
    for (uint i_2 = 0u; i_2 < 8u; i_2++)
    {
        Transform param_10 = row;
        Transform param_11 = local[i_2];
        Transform m = combine_monoid(param_10, param_11);
        TransformSeg transform = TransformSeg{ m.mat, m.translate };
        TransformSegRef trans_ref = TransformSegRef{ _278.conf.trans_alloc.offset + ((ix + i_2) * 24u) };
        param_12.offset = _278.conf.trans_alloc.offset;
        TransformSegRef param_13 = trans_ref;
        TransformSeg param_14 = transform;
        TransformSeg_write(param_12, param_13, param_14, v_71);
    }
}