#version 450 core
#ifdef GL_ES
precision mediump float;
#endif

uniform vec2 resolution;
uniform float time;

uniform sampler2D images[4];
layout (binding = 0,rgba32f) uniform image2D backbuffer;
//uniform image2DArray buffers;
uniform float ratios[4];
uniform float params[32];

out vec4 fragColor;

float random (in float x) {
  return fract(sin(x)*43758.5453123)-0.5;
}

vec4 image(int i) {
	vec2 st = gl_FragCoord.xy/resolution.xy;
  st.x *= ratios[i];
  st.x += (1-ratios[i])*0.5;
  st.x += 0.5*time;
  return texture2D(images[i],st);
}

void main (void) {
	vec4 img1 = mix(image(0),image(1),sin(time));
	vec4 img2 = mix(image(2),image(3),cos(time));
  ivec2 P = ivec2(gl_FragCoord.xy);
  vec4 buf = imageLoad(backbuffer,P);
  buf.rg = buf.gr;
  //buf.b = 0.0;
  vec4 i = mix(img1,img2,0.5);
  //P = ivec2(gl_FragCoord.xy);
  imageStore(backbuffer,P,i);
  i = mix(i,buf,0.8);
  //i = image(0);
  fragColor = i;
}