Pixel-Composer/shaders/sh_twirl/sh_twirl.fsh
2022-09-21 11:09:40 +07:00

22 lines
567 B
GLSL

//
// 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 + vec2(cos(ang), sin(ang)) * distance(center, pixelPos);
gl_FragColor = v_vColour * texture2D( gm_BaseTexture, tex / dimension );
}