#ifdef GL_ES
precision mediump float;
precision mediump int;
#endif

uniform sampler2D u_texture;

const float round = 0.23;

varying vec4 v_color;
varying vec2 v_texCoord;

void main() {
	vec4 color = texture2D(u_texture, v_texCoord.xy);
	color.a = 1.0 - color.r;
	color.rgb = vec3(0.0);
	color.a = float(int(color.a / round)) * round;
	if(color.a >= 1.0 - round){
	    color.a = 1.0;
	}
	gl_FragColor = color * v_color;
}