#extension GL_EXT_buffer_reference : require

#if VERTEX_SHADER

layout(buffer_reference, std430) readonly buffer CameraMatrices {
  mat4 view_projection;
  mat4 projection;
  mat4 view;
};

layout(push_constant) uniform constants {
  CameraMatrices camera_matrices;
} PushConstants;

vec2 positions[3] = vec2[](
    vec2(-0.5, 0.5),
    vec2(0.5, 0.5),
    vec2(0.0, -0.5)
);

vec3 colors[3] = vec3[](
    vec3(1.0, 0.0, 0.0),
    vec3(0.0, 1.0, 0.0),
    vec3(0.0, 0.0, 1.0)
);

layout(location = 0) out vec3 VertexColor;

void main() {
  VertexColor = colors[gl_VertexIndex];
  
  gl_Position = PushConstants.camera_matrices.view_projection * vec4(positions[gl_VertexIndex], 0.0, 1.0);
}

#endif

#if FRAGMENT_SHADER

layout(location = 0) in vec3 VertexColor;

layout(location = 0) out vec4 FragColor;

void main() {
  FragColor = vec4(VertexColor, 1.0);
}

#endif