wgpu/tests/out/msl/shadow.msl

// language: metal1.1
#include <metal_stdlib>
#include <simd/simd.h>

struct _mslBufferSizes {
    metal::uint size1;
};

constexpr constant unsigned c_max_lights = 10u;
struct Globals {
    metal::uint4 num_lights;
};
struct Light {
    metal::float4x4 proj;
    metal::float4 pos;
    metal::float4 color;
};
typedef Light type3[1];
struct Lights {
    type3 data;
};
constant metal::float3 c_ambient = {0.05, 0.05, 0.05};

float fetch_shadow(
    metal::uint light_id,
    metal::float4 homogeneous_coords,
    metal::depth2d_array<float, metal::access::sample> t_shadow,
    metal::sampler sampler_shadow
) {
    if (homogeneous_coords.w <= 0.0) {
        return 1.0;
    }
    metal::float2 flip_correction = metal::float2(0.5, -0.5);
    metal::float2 light_local = ((homogeneous_coords.xy * flip_correction) / metal::float2(homogeneous_coords.w)) + metal::float2(0.5, 0.5);
    float _e26 = t_shadow.sample_compare(sampler_shadow, light_local, static_cast<int>(light_id), homogeneous_coords.z / homogeneous_coords.w);
    return _e26;
}

struct fs_mainInput {
    metal::float3 raw_normal [[user(loc0), center_perspective]];
    metal::float4 position [[user(loc1), center_perspective]];
};
struct fs_mainOutput {
    metal::float4 member [[color(0)]];
};
fragment fs_mainOutput fs_main(
  fs_mainInput varyings [[stage_in]]
, constant Globals& u_globals [[user(fake0)]]
, constant Lights& s_lights [[user(fake0)]]
, metal::depth2d_array<float, metal::access::sample> t_shadow [[user(fake0)]]
, metal::sampler sampler_shadow [[user(fake0)]]
) {
    const auto raw_normal = varyings.raw_normal;
    const auto position = varyings.position;
    metal::float3 color = c_ambient;
    metal::uint i = 0u;
    metal::float3 normal = metal::normalize(raw_normal);
    bool loop_init = true;
    while(true) {
        if (!loop_init) {
            metal::uint _e40 = i;
            i = _e40 + 1u;
        }
        loop_init = false;
        metal::uint _e12 = i;
        metal::uint4 _e14 = u_globals.num_lights;
        if (_e12 >= metal::min(_e14.x, c_max_lights)) {
            break;
        }
        metal::uint _e19 = i;
        Light light = s_lights.data[_e19];
        metal::uint _e22 = i;
        float _e25 = fetch_shadow(_e22, light.proj * position, t_shadow, sampler_shadow);
        metal::float3 light_dir = metal::normalize(light.pos.xyz - position.xyz);
        float diffuse = metal::max(0.0, metal::dot(normal, light_dir));
        metal::float3 _e34 = color;
        color = _e34 + ((_e25 * diffuse) * light.color.xyz);
    }
    metal::float3 _e43 = color;
    return fs_mainOutput { metal::float4(_e43, 1.0) };
}