#ifdef GL_ES
precision mediump float;
#endif

uniform float time;
//uniform vec2 mouse;
uniform vec2 resolution;

// bonniemathew@gmail.com

//vec3 COLOR1 = vec3(0.0, 0.0, 0.50);
//vec3 COLOR2 = vec3(0.30, .0, 0.0);

const vec3 COLOR1 = vec3(0.0, 0.0, 0.0);
vec3 COLOR2 = COLOR1;

float BLOCK_WIDTH = 0.01; 

void main( void ) {

	
	vec2 position = ( gl_FragCoord.xy / resolution.xy );
	vec3 final_color = vec3(1.0);
	
	// For creating the BG pattern
	float c1 = mod(position.x, 2.0 * BLOCK_WIDTH);
	c1 = step(position.x*0.01, c1);
	float c2 = mod(position.y, 2.0 * BLOCK_WIDTH);
	c2 = step(BLOCK_WIDTH, c2);
	
	final_color = mix( position.x * COLOR1,  position.y * COLOR2, c1 * c2);
	
	
	 // creating the wave
	position = -1.0 + 2.0 * position;
	float lineWidth = 10.0;
	vec2 sPos = position ;
	for( float i = 0.0; i < 13.; i++) {
		sPos.y += ((0.07*cos(time)) * tan(position.x + i/5.0+ sin(time*0.5)));
		
		lineWidth  =  abs(1.0 / (750.0 * sPos.y));
		final_color = final_color + vec3(lineWidth * 1.9f, lineWidth*1.9f, lineWidth * 0.); 
		
	}
	
	gl_FragColor = vec4(final_color, 1.0);
}