pixel wave shader

fixed2 uv = i.uv;

// for a 32x32 texture, could also be a parameter.
fixed pixelWidth = 1.0 / 32.0;
fixed pixelHeight = 1.0 / 32.0;

// make it so the UV is always a multiple of pixelWidth and pixelHeight.
uv = fixed2(round(uv.x / pixelWidth) * pixelWidth, round(uv.y / pixelHeight) * pixelHeight);

// offset the UV according to the sine value of the current time.
fixed waveSpeed = 0.0625;
fixed waveLength = 8;
fixed2 uvOffset = fixed2(sin(uv.y * waveLength + _Time.z) * waveSpeed, sin(uv.x * waveLength + _Time.z) * waveSpeed);
uv.x += uvOffset.x;
uv.y += uvOffset.y;

i.uv = uv;