oculus1
diff sdr.glsl @ 13:464e1d135d68
hurraaaay!
author | John Tsiombikas <nuclear@member.fsf.org> |
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date | Sat, 21 Sep 2013 03:00:47 +0300 |
parents | |
children | cceffea995a4 |
line diff
1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000 1.2 +++ b/sdr.glsl Sat Sep 21 03:00:47 2013 +0300 1.3 @@ -0,0 +1,44 @@ 1.4 +uniform sampler2D tex; 1.5 +uniform float aspect, scale; 1.6 +uniform float lens_center_offset; 1.7 +uniform vec4 dist_factors; 1.8 + 1.9 +vec2 distort_texcoords(in vec2 tc, out float dbgrad); 1.10 +float barrel_scale(float x, in vec4 k); 1.11 + 1.12 +void main() 1.13 +{ 1.14 + float dbgrad; 1.15 + vec2 tc = distort_texcoords(gl_TexCoord[0].xy, dbgrad); 1.16 + 1.17 + gl_FragColor.rgb = texture2D(tex, tc).rgb; 1.18 + gl_FragColor.rgb += mix(vec3(1.0, 1.0, 0.0), vec3(0.0), smoothstep(0.01, 0.05, dbgrad)); 1.19 + gl_FragColor.a = 1.0; 1.20 +} 1.21 + 1.22 +vec2 distort_texcoords(in vec2 tc, out float dbgrad) 1.23 +{ 1.24 + // map tc [0, 1] -> [-1, 1] 1.25 + vec2 pt = tc * 2.0 - 1.0; 1.26 + 1.27 + pt.x += lens_center_offset * 2.0; 1.28 + pt.y /= aspect; // correct for aspect ratio 1.29 + 1.30 + float rad = barrel_scale(dot(pt, pt), dist_factors); 1.31 + pt *= rad; // scale the point by the computer distortion radius 1.32 + 1.33 + dbgrad = length(pt) * rad; 1.34 + 1.35 + pt.y *= aspect; 1.36 + pt.x -= lens_center_offset * 2.0; 1.37 + 1.38 + // map back to range [0, 1] 1.39 + return pt * 0.5 + 0.5; 1.40 +} 1.41 + 1.42 +float barrel_scale(float rad, in vec4 k) 1.43 +{ 1.44 + float radsq = rad * rad; 1.45 + float radquad = radsq * radsq; 1.46 + return k.x + k.y * radsq + k.z * radquad + k.w * radquad * radsq; 1.47 +}