varying vec2 vUv;

uniform sampler2D uTarget;
uniform float aspectRatio;
uniform vec3 uColor;
uniform vec2 uPointer;
uniform float uRadius;

void main() {
    vec2 p = vUv - uPointer.xy;

    p.x *= aspectRatio;

    vec3 splat = exp(-dot(p, p) / uRadius) * uColor;

    vec3 base = texture2D(uTarget, vUv).xyz;

    gl_FragColor = vec4(base + splat, 1.0);
}