Pixel-Composer/shaders/sh_twirl/sh_twirl.fsh

22 lines
582 B
Plaintext
Raw Normal View History

2022-01-13 05:24:03 +01:00
//
// Simple passthrough fragment shader
//
varying vec2 v_vTexcoord;
varying vec4 v_vColour;
uniform vec2 dimension;
uniform vec2 center;
uniform float strength;
uniform float radius;
void main() {
vec2 pixelPos = v_vTexcoord * dimension;
vec2 to = pixelPos - center;
float dis = distance(center, pixelPos);
float eff = 1. - clamp(dis / radius, 0., 1.);
float ang = atan(to.y, to.x) + eff * strength;
vec2 tex = center / dimension + vec2(cos(ang), sin(ang)) * distance(center / dimension, v_vTexcoord);
gl_FragColor = v_vColour * texture2D( gm_BaseTexture, tex );
}