#version 120 uniform vec3 uniform_color; void main() { vec2 pos = gl_PointCoord - vec2(0.5, 0.5); float sq_radius = pos.x * pos.x + pos.y * pos.y; if (sq_radius > 0.25) discard; else if (sq_radius > 0.180625) gl_FragColor = vec4(0.5 * uniform_color, 1.0); else gl_FragColor = vec4(uniform_color, 1.0); }