#version 400

in vec3 pos;
in float radius;

uniform mat4 mView;
uniform mat4 projection;
uniform vec2 screenSize;

out float thickness;

void main() {
    //calculate normal
    vec3 normal;
    normal.xy = gl_PointCoord * 2.0 - 1.0;
    float r2 = dot(normal.xy, normal.xy);

    if (r2 > 1.0f) {
        discard;
    }

    float nz = sqrt(1 - r2);

    //thickness = nz * 1.25 * 2.0f * exp(-r2 * 2.0f);
    //thickness = 1 - r2;
    //thickness = 1;
    thickness = 0.5f;
}