#version 140 in mediump vec2 var_texcoord0; out vec4 out_fragColor; uniform mediump sampler2D tex0; uniform fs_uniforms { mediump vec4 resolution; }; // https://www.shadertoy.com/view/XdXXD4 void main() { vec2 uv = var_texcoord0.xy; vec4 col = texture(tex0, uv ); // scanline float scanline = sin(uv.y*resolution.y)*0.04; col -= scanline; out_fragColor = col; }