out vec4 FragColor;

uniform sampler2D uTexMain;
uniform sampler2D uTexDudv;
uniform vec2 uInvRes;
uniform float uTime;

in vec2 aUv;

void main()
{
   vec2 ssuv = gl_FragCoord.xy*uInvRes;
   vec4 dudva = texture( uTexDudv, aUv + vec2(uTime*0.04f,uTime*0.03f) );
   vec4 dudvb = texture( uTexDudv, aUv - vec2(uTime*0.1,uTime*0.054) );

   vec2 distortamt = (dudva.rg-0.5) * (dudvb.ba-0.5) * 2.0;

   vec4 reflected = texture( uTexMain, ssuv+distortamt );
   FragColor = vec4(reflected.rgb*0.9,reflected.a);
}