1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/mbrot.glsl	Sat Nov 18 20:04:16 2017 +0200
     1.3 @@ -0,0 +1,30 @@
     1.4 +// vi:ft=glsl:
     1.5 +#define ITER	96
     1.6 +
     1.7 +uniform float view_scale;
     1.8 +uniform vec2 view_center;
     1.9 +
    1.10 +float mbrot_dist_point(in vec2 c, in vec2 p)
    1.11 +{
    1.12 +	vec2 z = c;
    1.13 +	float mindist_sq = 8192.0;
    1.14 +
    1.15 +	for(int i=0; i<ITER; i++) {
    1.16 +		float x = (z.x * z.x - z.y * z.y) + c.x;
    1.17 +		float y = (z.x * z.y + z.x * z.y) + c.y;
    1.18 +
    1.19 +		z = vec2(x, y);
    1.20 +		mindist_sq = min(mindist_sq, dot(z, z)); 
    1.21 +	}
    1.22 +
    1.23 +	return sqrt(mindist_sq);
    1.24 +}
    1.25 +
    1.26 +void main()
    1.27 +{
    1.28 +	vec2 c = gl_TexCoord[0].xy * view_scale - view_center;
    1.29 +	float m = 1.0 - mbrot_dist_point(c, vec2(0.0, 0.0));
    1.30 +
    1.31 +	gl_FragColor.rgb = vec3(m, m, m);
    1.32 +	gl_FragColor.a = 1.0;
    1.33 +}