#!amber

DEVICE_EXTENSION VK_KHR_acceleration_structure
DEVICE_EXTENSION VK_KHR_ray_tracing_pipeline
DEVICE_EXTENSION VK_KHR_buffer_device_address
DEVICE_FEATURE   RayTracingPipelineFeaturesKHR.rayTracingPipeline
DEVICE_FEATURE   AccelerationStructureFeaturesKHR.accelerationStructure
DEVICE_FEATURE   BufferDeviceAddressFeatures.bufferDeviceAddress

SHADER ray_generation raygeneration1 GLSL
  #version 460 core
  #extension GL_EXT_ray_tracing : require
  layout(location = 0) rayPayloadEXT int payload;
  layout(set = 0, binding = 0) uniform accelerationStructureEXT gScene;

  void main()
  {
    float TMin      = 0.1;
    float TMax      = 10;
    vec3  Origin;
    vec3  Direction = vec3(0, 0, 1);

    // Ray origin at -1, 0: front facing opaque first (at z = 1)
    Origin    = vec3(-1, 0, -2);

    payload = 0;
    traceRayEXT(gScene, gl_RayFlagsNoneEXT, 0xff, 0, 0, 0, Origin, TMin, Direction, TMax, 0);

    payload = 1;
    traceRayEXT(gScene, gl_RayFlagsCullFrontFacingTrianglesEXT, 0xff, 0, 0, 0, Origin, TMin, Direction, TMax, 0);

    payload = 2;
    traceRayEXT(gScene, gl_RayFlagsCullOpaqueEXT, 0xff, 0, 0, 0, Origin, TMin, Direction, TMax, 0);

    Origin    = vec3(1, 0, -2);

    payload = 3;
    traceRayEXT(gScene, gl_RayFlagsNoneEXT, 0xff, 0, 0, 0, Origin, TMin, Direction, TMax, 0);

    payload = 4;
    traceRayEXT(gScene, gl_RayFlagsCullBackFacingTrianglesEXT, 0xff, 0, 0, 0, Origin, TMin, Direction, TMax, 0);

    payload = 5;
    traceRayEXT(gScene, gl_RayFlagsCullNoOpaqueEXT, 0xff, 0, 0, 0, Origin, TMin, Direction, TMax, 0);
}
END

SHADER closest_hit closesthit1 GLSL
  #version 460 core
  #extension GL_EXT_ray_tracing : require
  layout(location = 0) rayPayloadInEXT int payload;
  layout(set = 0, binding = 1, r32f) uniform image1D result;

  void main()
  {
    imageStore(result, payload, vec4(round(gl_HitTEXT), 0, 0, 0));
  }
END

ACCELERATION_STRUCTURE BOTTOM_LEVEL triangle_blas
  # Front facing opaque triangle at -1, 0, 1
  GEOMETRY TRIANGLES
    FLAGS OPAQUE
    -1.0 -0.75 1.0
    -1.75 0.75 1.0
    -0.25 0.75 1.0
  END
  # Back facing triangle at -1, 0, 2
  GEOMETRY TRIANGLES
    -1.0 -0.75 2.0
    -0.25 0.75 2.0
    -1.75 0.75 2.0
  END
  # Back facing triangle at 1, 0, 1
  GEOMETRY TRIANGLES
    1.0 -0.75 1.0
    1.75 0.75 1.0
    0.25 0.75 1.0
  END
  # Front facing opaque triangle at 1, 0, 2
  GEOMETRY TRIANGLES
    FLAGS OPAQUE
    1.0 -0.75 2.0
    0.25 0.75 2.0
    1.75 0.75 2.0
  END
END

ACCELERATION_STRUCTURE TOP_LEVEL triangle_tlas
  BOTTOM_LEVEL_INSTANCE triangle_blas
  END
END

IMAGE outbuf FORMAT R32_SFLOAT DIM_1D WIDTH 6 FILL 0

PIPELINE raytracing my_rtpipeline
  MAX_RAY_PAYLOAD_SIZE 16
  MAX_RAY_HIT_ATTRIBUTE_SIZE 8
  MAX_RAY_RECURSION_DEPTH 1
  BIND ACCELERATION_STRUCTURE triangle_tlas DESCRIPTOR_SET 0 BINDING 0
  BIND BUFFER outbuf AS storage_image DESCRIPTOR_SET 0 BINDING 1
  SHADER_GROUP group_rgen raygeneration1
  SHADER_GROUP group_hits closesthit1
  SHADER_BINDING_TABLE sbt_raygen
    group_rgen
  END
  SHADER_BINDING_TABLE sbt_hit
    group_hits
  END
END

RUN my_rtpipeline RAYGEN sbt_raygen HIT sbt_hit 1 1 1

EXPECT outbuf IDX 0 EQ 3 4 4 3 4 4