#define iChannel0 inputImageTexture
#define iChannel1 inputImageTexture2
#define texture(a,b) texture2D(a,fract(b))
#define fragColor gl_FragColor
precision highp float;

varying highp vec2 textureCoordinate;

uniform sampler2D inputImageTexture;
uniform sampler2D inputImageTexture2;

void main()
{
    highp vec2 uv = textureCoordinate;

    uv *= 2.0;

    float i = floor(uv.x) + floor(uv.y);
    i = mod(i, 2.0);

    fragColor = mix(texture(iChannel0, uv), texture(iChannel0, uv), i);
}
