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dodocinho/edges.frag

Created September 25, 2022 22:58
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  1. dodocinho created this gist Sep 25, 2022.
    110 changes: 110 additions & 0 deletions edges.frag
    View file
    Original file line number Diff line number Diff line change
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    /*{
    "CREDIT": "by VIDVOX",
    "ISFVSN": "2",
    "CATEGORIES": [
    "Stylize"
    ],
    "INPUTS": [
    {
    "NAME": "inputImage",
    "TYPE": "image"
    },
    {
    "NAME": "intensity",
    "TYPE": "float",
    "MIN": 0.0,
    "MAX": 50.0,
    "DEFAULT": 50.0
    },
    {
    "NAME": "threshold",
    "TYPE": "float",
    "MIN": 0.0,
    "MAX": 1.0,
    "DEFAULT": 0.0
    },
    {
    "NAME": "sobel",
    "TYPE": "bool",
    "DEFAULT": 1.0
    },
    {
    "NAME": "opaque",
    "TYPE": "bool",
    "DEFAULT": true
    }
    ]
    }*/

    #if __VERSION__ <= 120
    varying vec2 left_coord;
    varying vec2 right_coord;
    varying vec2 above_coord;
    varying vec2 below_coord;

    varying vec2 lefta_coord;
    varying vec2 righta_coord;
    varying vec2 leftb_coord;
    varying vec2 rightb_coord;
    #else
    in vec2 left_coord;
    in vec2 right_coord;
    in vec2 above_coord;
    in vec2 below_coord;

    in vec2 lefta_coord;
    in vec2 righta_coord;
    in vec2 leftb_coord;
    in vec2 rightb_coord;
    #endif

    float gray(vec4 n)
    {
    return (n.r + n.g + n.b)/3.0;
    }

    void main()
    {

    vec4 color = IMG_THIS_PIXEL(inputImage);
    vec4 colorL = IMG_NORM_PIXEL(inputImage, left_coord);
    vec4 colorR = IMG_NORM_PIXEL(inputImage, right_coord);
    vec4 colorA = IMG_NORM_PIXEL(inputImage, above_coord);
    vec4 colorB = IMG_NORM_PIXEL(inputImage, below_coord);

    vec4 colorLA = IMG_NORM_PIXEL(inputImage, lefta_coord);
    vec4 colorRA = IMG_NORM_PIXEL(inputImage, righta_coord);
    vec4 colorLB = IMG_NORM_PIXEL(inputImage, leftb_coord);
    vec4 colorRB = IMG_NORM_PIXEL(inputImage, rightb_coord);

    float gx = (0.0);
    float gy = (0.0);
    if (sobel) {
    gx = (-1.0 * gray(colorLA)) + (-2.0 * gray(colorL)) + (-1.0 * gray(colorLB)) + (1.0 * gray(colorRA)) + (2.0 * gray(colorR)) + (1.0 * gray(colorRB));
    gy = (1.0 * gray(colorLA)) + (2.0 * gray(colorA)) + (1.0 * gray(colorRA)) + (-1.0 * gray(colorRB)) + (-2.0 * gray(colorB)) + (-1.0 * gray(colorLB));
    }
    else {
    gx = (-1.0 * gray(colorLA)) + (-1.0 * gray(colorL)) + (-1.0 * gray(colorLB)) + (1.0 * gray(colorRA)) + (1.0 * gray(colorR)) + (1.0 * gray(colorRB));
    gy = (1.0 * gray(colorLA)) + (1.0 * gray(colorA)) + (1.0 * gray(colorRA)) + (-1.0 * gray(colorRB)) + (-1.0 * gray(colorB)) + (-1.0 * gray(colorLB));
    }

    float bright = pow(gx*gx + gy*gy,0.5);
    vec4 final = color * bright;

    // if the brightness is below the threshold draw black
    if (bright < threshold) {
    if (opaque)
    final = vec4(0.0, 0.0, 0.0, 1.0);
    else
    final = vec4(0.0, 0.0, 0.0, 0.0);
    }
    else {
    final.rgb = final.rgb * intensity;
    if (opaque)
    final.a = 1.0;
    else
    final.a = color.a;
    }

    gl_FragColor = vec4(final.r * 1.2, final.g * 0.5, final.b * 0.1, final.a);
    }