vello/piet-gpu/shader/gen/transform_reduce.msl

#pragma clang diagnostic ignored "-Wmissing-prototypes"

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

using namespace metal;

struct TransformRef
{
    uint offset;
};

struct Transform
{
    float4 mat;
    float2 translate;
};

struct SceneBuf
{
    uint scene[1];
};

struct Alloc
{
    uint offset;
};

struct Config
{
    uint n_elements;
    uint n_pathseg;
    uint width_in_tiles;
    uint height_in_tiles;
    Alloc tile_alloc;
    Alloc bin_alloc;
    Alloc ptcl_alloc;
    Alloc pathseg_alloc;
    Alloc anno_alloc;
    Alloc trans_alloc;
    Alloc bbox_alloc;
    uint n_trans;
    uint trans_offset;
    uint pathtag_offset;
    uint linewidth_offset;
    uint pathseg_offset;
};

struct ConfigBuf
{
    Config conf;
};

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

struct OutBuf
{
    Transform_1 outbuf[1];
};

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

constant uint3 gl_WorkGroupSize [[maybe_unused]] = uint3(512u, 1u, 1u);

static inline __attribute__((always_inline))
Transform Transform_read(thread const TransformRef& ref, const device SceneBuf& v_49)
{
    uint ix = ref.offset >> uint(2);
    uint raw0 = v_49.scene[ix + 0u];
    uint raw1 = v_49.scene[ix + 1u];
    uint raw2 = v_49.scene[ix + 2u];
    uint raw3 = v_49.scene[ix + 3u];
    uint raw4 = v_49.scene[ix + 4u];
    uint raw5 = v_49.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;
}

kernel void main0(const device ConfigBuf& _161 [[buffer(1)]], const device SceneBuf& v_49 [[buffer(2)]], device OutBuf& _251 [[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[512];
    uint ix = gl_GlobalInvocationID.x * 8u;
    TransformRef ref = TransformRef{ _161.conf.trans_offset + (ix * 24u) };
    TransformRef param = ref;
    Transform agg = Transform_read(param, v_49);
    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_49);
        agg = combine_monoid(param_4, param_5);
    }
    sh_scratch[gl_LocalInvocationID.x] = agg;
    for (uint i_1 = 0u; i_1 < 9u; i_1++)
    {
        threadgroup_barrier(mem_flags::mem_threadgroup);
        if ((gl_LocalInvocationID.x + (1u << i_1)) < 512u)
        {
            Transform other = sh_scratch[gl_LocalInvocationID.x + (1u << i_1)];
            Transform param_6 = agg;
            Transform param_7 = other;
            agg = combine_monoid(param_6, param_7);
        }
        threadgroup_barrier(mem_flags::mem_threadgroup);
        sh_scratch[gl_LocalInvocationID.x] = agg;
    }
    if (gl_LocalInvocationID.x == 0u)
    {
        _251.outbuf[gl_WorkGroupID.x].mat = agg.mat;
        _251.outbuf[gl_WorkGroupID.x].translate = agg.translate;
    }
}