update

resources/shaders/options_120.fs

@@ -0,0 +1,22 @@
+// version 120 is needed for gl_PointCoord
+#version 120
+
+uniform vec4 uniform_color;
+uniform float percent_outline_radius;
+uniform float percent_center_radius;
+
+vec4 calc_color(float radius, vec4 color)
+{
+    return ((radius < percent_center_radius) || (radius > 1.0 - percent_outline_radius)) ?
+            vec4(0.5 * color.rgb, color.a) : color;
+}
+
+void main()
+{
+    vec2 pos = (gl_PointCoord - 0.5) * 2.0;
+    float radius = length(pos);
+    if (radius > 1.0)
+        discard;
+
+    gl_FragColor = calc_color(radius, uniform_color);
+}