raylib/examples/shaders/resources/shaders/glsl120/pixelizer.fs

#version 120

// Input vertex attributes (from vertex shader)
varying vec2 fragTexCoord;
varying vec4 fragColor;

// Input uniform values
uniform sampler2D texture0;
uniform vec4 colDiffuse;

// NOTE: Add here your custom variables 

// NOTE: Render size values must be passed from code
const float renderWidth = 800.0;
const float renderHeight = 450.0;

float pixelWidth = 5.0;
float pixelHeight = 5.0;

void main() 
{ 
    float dx = pixelWidth*(1.0/renderWidth);
    float dy = pixelHeight*(1.0/renderHeight);
    
    vec2 coord = vec2(dx*floor(fragTexCoord.x/dx), dy*floor(fragTexCoord.y/dy));
    
    vec3 tc = texture2D(texture0, coord).rgb;

    gl_FragColor = vec4(tc, 1.0);
}