---

/*{
	"CREDIT": "mojovideotech",
	"DESCRIPTION": "",
	"CATEGORIES": [],
	"INPUTS": [
		{
			"MAX": [
				10,
				10
			],
			"MIN": [
				-10,
				-10
			],
			"DEFAULT": [
				0.5,
				-0.5
			],
			"NAME": "offset",
			"TYPE": "point2D"
		},
		{
			"MAX": [
				0.1,
				0.01
			],
			"MIN": [
				0.0001,
				0.00001
			],
			"DEFAULT": [
				0.005,
				0.005
			],
			"NAME": "matrix",
			"TYPE": "point2D"
		},
		{
			"NAME": "size",
			"TYPE": "float",
			"DEFAULT": 30,
			"MIN": 9,
			"MAX": 120
		},
		{
			"NAME": "speed",
			"TYPE": "float",
			"DEFAULT": 10,
			"MIN": 1.1,
			"MAX": 32
		},
		{
			"NAME": "hue",
			"TYPE": "float",
			"DEFAULT": 0,
			"MIN": -0.3,
			"MAX": 0.3
		}
	]
}
*/

// RetroTechicolorComputer by mojovideotech
// based on :
// http://glslsandbox.com/e#3613.1

#ifdef GL_ES
precision mediump float;
#endif


float round(float v)
{
	if(v - floor(v) >= 0.5) return floor(v)+1.0;
	else return floor(v);

}

vec2 round(vec2 v)
{
	vec2 ret = vec2(0.0);
	if(v.x - floor(v.x) >= 0.5) ret.x = floor(v.x)+1.0;
	else ret.x = floor(v.x);
	if(v.y - floor(v.y) >= 0.5) ret.y = floor(v.y)+1.0;
	else ret.y = floor(v.y);
	return ret;
}

float triwave(float x)
{
	return 1.0-4.0*abs(0.5-fract(0.5*x + 0.25));
}

float rand(vec2 co){
	float t = round(TIME*speed);
	float tt = round(log2(TIME));
    return fract(sin(dot(co.xy ,vec2(matrix.xy))) * tt*t);
}

float pixelsize = floor(size);

void main( void ) {

	vec2 position = ( gl_FragCoord.xy);
	
	vec3 color = vec3(0.0);
	
	vec2 rposition = round(((position-(pixelsize/2.0))/pixelsize));
	
	color = vec3(rand(rposition)-hue,rand(rposition+offset.x)-abs(hue*1.25),rand(rposition+offset.y)+hue);
	
	color *= vec3(abs(log2((position.x+size))*0.5) / abs(log2((position.y+size))*0.5));
	color *= vec3(clamp( abs(triwave(position.x/pixelsize))*3.0 , 0.125, 0.9 ));
	color *= vec3(clamp( abs(triwave(position.y/pixelsize))*3.0 , 0.125 , 0.9));
	
	
	
	gl_FragColor = vec4(color, 1.0 );
}