---

/*{
	"CREDIT": "mojovideotech",
	"CATEGORIES": [
		"color",
		"gradient",
		"rainbow"
	],
	"DESCRIPTION": "mod of https://www.shadertoy.com/view/ltVXW3 by Loeizd.  cheap rainbow using mix",
	"INPUTS": [
		{
			"NAME": "blend",
			"TYPE": "float",
			"DEFAULT": 0.33,
			"MIN": -0.5,
			"MAX": 1
		},
		{
			"NAME": "Rx",
			"TYPE": "float",
			"MIN": 0,
			"MAX": 6,
			"DEFAULT": 2
		},
		{
			"NAME": "Gx",
			"TYPE": "float",
			"MIN": 0,
			"MAX": 6,
			"DEFAULT": 3
		},
		{
			"NAME": "Bx",
			"TYPE": "float",
			"MIN": 0,
			"MAX": 6,
			"DEFAULT": 1
		},
		{
			"NAME": "vertical",
			"TYPE": "bool",
			"DEFAULT": false
		}
	]
}
*/

////////////////////////////////////////////////////////////
// RainbowGradientMixer   by mojovideotech
//
// mod of
// shadertoy.com\/ltVXW3  by Loeizd
//
// Creative Commons Attribution-NonCommercial-ShareAlike 3.0
////////////////////////////////////////////////////////////


void main()
{
	vec2 uv = isf_FragNormCoord.xy;
	if (vertical) uv.xy = uv.yx;
    float a = blend / 2.0 - 0.25;
    vec3 m = abs(uv.x * 2.0 - vec3(Rx,Gx,Bx) / 3.0);
    m.gb = 1.0 - m.gb;
    m += a;
    m = smoothstep(0.0, 1.0, m);

    gl_FragColor = sqrt(vec4(m, 1.0));
}