#version 430

layout(quads, equal_spacing, ccw) in;  // Define the type of patch (e.g., quads)

out vec3 frag_position;  // Ensure this matches the input in fragment.glsl

void main()
{
    // Interpolate the position using the barycentric coordinates from tessellation
    vec3 pos = mix(mix(gl_in[0].gl_Position.xyz, gl_in[1].gl_Position.xyz, gl_TessCoord.x),
                   mix(gl_in[3].gl_Position.xyz, gl_in[2].gl_Position.xyz, gl_TessCoord.x),
                   gl_TessCoord.y);
    
    frag_position = pos;

    gl_Position = vec4(pos, 1.0);
}