Mixed Gradient

// Author:Cameron Saunders 3178885
//Course:ShaderArt
// Title: Mixed Gradient/Emotions

#ifdef GL_ES
precision mediump float;
#endif

//PI needs to be declared
#define PI 3.14159265359

uniform vec2 u_resolution;
uniform vec2 u_mouse;
uniform float u_time;

//Pick 2 Colors variables to Mix
vec3 colorA = vec3(0.912,0.328,0.551);
vec3 colorB = vec3(0.767,0.090,1.000);

//Determine the points at which the Grandient will occur
float plot(vec2 st, float pct){
    return smoothstep(pct-0.194, pct, st.y) -
           smoothstep(pct, pct+-1.110, st.y);
}
void main() {
    
    //Normalize Canvas
    vec2 st = gl_FragCoord.xy/u_resolution.xy;
    //declare color variable
    vec3 color = vec3(0.297,0.320,0.910);
    //Normalize Mouse posistion
    vec2 mouseXY = u_mouse / u_resolution;
    vec3 pct = vec3(st.x);
    //Determine Posistion and Color variables for each
    //shaping fnction
    pct.r = smoothstep(-1.008,1.600,st.x);
    pct.g = sin(st.x*PI);
    pct.b = pow(st.x,0.460);
    
    //Mix vec3 selected Colors A and B
    color = mix(colorA,colorB,pct);
    
    color = mix(color,vec3(1.000,0.047,0.009),plot(st,pct.r));
    color = mix(color,vec3(1.000,0.470,0.002),plot(st,pct.g));
    
    //Alter where gradient happens using "smoothstep"
    //and GLSL shaping functions.
    
    //Alter Color Brightness
    gl_FragColor = vec4(color,2.072);