Kevin wiseoldduck
wiseoldduck
/ greyscale.frag
Last active
January 19, 2017 08:28
A simple glsl color -> greyscale shader, using luminosity method
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| // fragment shader | |
| // | |
| // RGBA color to RGBA greyscale | |
| // | |
| // smooth transition based on u_colorFactor: 0.0 = original, 1.0 = greyscale | |
| // | |
| // http://www.johndcook.com/blog/2009/08/24/algorithms-convert-color-grayscale/ | |
| // "The luminosity method is a more sophisticated version of the average method. | |
| // It also averages the values, but it forms a weighted average to account for human perception. | |
| // We’re more sensitive to green than other colors, so green is weighted most heavily. The formula |