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HTML

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HTML preprocessors can make writing HTML more powerful or convenient. For instance, Markdown is designed to be easier to write and read for text documents and you could write a loop in Pug.

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Insecure Resource

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CSS

About CSS Preprocessors

CSS preprocessors help make authoring CSS easier. All of them offer things like variables and mixins to provide convenient abstractions.

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CSS Base

About CSS Base

It's a common practice to apply CSS to a page that styles elements such that they are consistent across all browsers. We offer two of the most popular choices: normalize.css and a reset. Or, choose Neither and nothing will be applied.

Vendor Prefixing

About Vendor Prefixing

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JavaScript

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JavaScript preprocessors can help make authoring JavaScript easier and more convenient.

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Babel includes JSX processing.

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HTML
!

CSS 

              
                body{
  margin:0;
}
!

JS 

              
                var gaps=[];
var numGaps=100;
var showInfo=true;
var centre;
var step;
var maxW=step;

var nX=0;
var nXInc=0.005;
var nY=0;
var nYInc=0.05;

function setup() {
  createCanvas(windowWidth, windowHeight);
  step=40;
  colorMode(HSB);
  centre=createVector(width/2, height/2);
  
  for(var j=0; j<floor(height/step); j++){
    for(var i=0; i<floor(width/step); i++){
      var g=new Gap(centre, 0,0,step, step);
      g.update(-width/2+i*step+step/2, -height/2+j*step+step/2);
      g.findOuter();
      g.findOuter2();
      gaps.push(g);
    }
  }

}

function draw() {
  background(0);
  gaps.forEach(function(g){
    g.showBeam2();
    g.run();
  });
  nX+=nXInc;
  nY+=nYInc;
  push();
  fill(0,0,100,0.2);
  textAlign(CENTER);
  textSize(height/16);
  text("Move the mouse", width/2, height*0.7);
  pop();
}

function mouseDragged(){
  gaps[0].update(mouseX-centre.x, mouseY-centre.y);
  // gaps[0].findOuter();
  gaps[0].findOuter2();
}

function nomouseDragged(){
  centre.x=mouseX;
  centre.y=mouseY;
  
}

function Gap(c,x,y,ow,oh) {
  var pivot=null;
  var verts=[];
  var outVerts=[];
  var startV=null;
  var startA=TWO_PI;
  var endV=null;
  var endA=0;
  var nearV=null;
  var nearD=width*2;
  var farV=null;
  var farD=0;
  var farStartV=null;
  var farEndV=null;
  var farFarV=null;
  var w=ow;
  var h=oh;
  var lightArea=constrain(w*h/(maxW*maxW),0,1);
  var isInside=false;
  var isHalfInside=false;
  var controlSize=0.1;
  var throbA=random(TWO_PI);
  var throbInc=PI/100;
  var dynaSize=0;
  var hCol=random(360);
  
  var nearVerts=[];
  var farVerts=[];
  var drift=createVector(1, 1).mult(0.2);
  
  this.run=function(){
    var dynaSize=1-constrain(dist(x,y,mouseX-c.x,mouseY-c.y)/(width/8),0,1);
    pivot.add(drift);
    edges();
    w=dynaSize*ow;
    h=dynaSize*oh;
    lightArea=constrain(w*h/(maxW*maxW),0,1);
    this.update(pivot.x, pivot.y);
    this.findOuter2();
  }

  function edges(){
    if(pivot.x>width/2) pivot.x=-width/2;
    if(pivot.x<-width/2) pivot.x=width/2;
    if(pivot.y>height/2) pivot.y=-height/2;
    if(pivot.y<-height/2) pivot.y=height/2;
  }
  
  this.update=function(nx,ny){
    pivot=createVector(nx, ny);
    x=nx;
    y=ny;
    verts=[];
    outVerts=[];
    var v, ov;
    var inCount=0;
    var vMult=width/pivot.mag();
    v=createVector(x-w/2, y-h/2);
    verts.push(v);
    ov=v.copy().mult(vMult);
    inCount+=(v.x>ov.x && v.y>ov.y)?1:0;
    outVerts.push(ov);
    v=createVector(x+w/2, y-h/2);
    verts.push(v);
    ov=v.copy().mult(vMult)
    inCount+=(v.x<ov.x && v.y>ov.y)?1:0;
    outVerts.push(ov);v=createVector(x+w/2, y+h/2);
    verts.push(v);
    ov=v.copy().mult(vMult)
    inCount+=(v.x<ov.x && v.y<ov.y)?1:0;
    outVerts.push(ov);v=createVector(x-w/2, y+h/2);
    verts.push(v);
    ov=v.copy().mult(vMult)
    inCount+=(v.x>ov.x && v.y<ov.y)?1:0;
    outVerts.push(ov);// console.log(verts);
    isInside=inCount>=4;
    isHalfInside=(inCount>=2 && !isInside);
  }
  
  this.showBox=function(){
    var intensity=1-pivot.mag()/(width*0.71);
    rectMode(CENTER);
    push();
    translate(c.x, c.y);
    noFill();
    stroke(50,100,100,1);
    rect(x,y,w,h);
    pop();
  }
  
  this.show=function(){
    var intensity=1-pivot.mag()/(width*0.71);
    rectMode(CENTER);
    push();
    translate(c.x, c.y);
    fill(intensity*200+50,200);
    noStroke();
    beginShape();
    verts.forEach(function(v){
      vertex(v.x, v.y);
    });
    endShape(CLOSE);
    stroke(255,150,0,255);
    noFill();
    beginShape();
    outVerts.forEach(function(v){
      vertex(v.x, v.y);
    });
    endShape(CLOSE);
    pop();
  }
  
  this.findOuter2=function(){
      nearVerts=[];
      var far=0;
      var farthest=-1;
      verts.forEach(function(v,i){
        nearVerts[i]={
          v: v.copy(),
          d: v.mag(),
          h: v.heading()+TWO_PI
        }
        if(v.mag()>far){
          far=v.mag();
          farthest=i;
        }
      });
      if(isHalfInside){
        //get two points of near side by brute force
        if(pivot.x-w/2<0 && pivot.x+w/2>0){
          if(pivot.y<0){
            nearVerts.splice(0,2);
          } else {
            nearVerts=nearVerts.splice(0,2);
          }
        }
        if(pivot.y-h/2<0 && pivot.y+h/2>0){
          if(pivot.x<0){
            nearVerts=nearVerts.splice(1,2);
          } else {
            nearVerts.splice(1,2);
          }
        }
        nearVerts.sort(function(a,b){
          return a.h-b.h;
        });
      } else {
        nearVerts.splice(farthest,1);
        nearVerts.sort(function(a,b){
          return a.h-b.h;
        });
      }

      farVerts=[];
      var near=width*2;
      var nearest=-1;
      outVerts.forEach(function(v,i){
        farVerts[i]={
          v: v.copy(),
          d: v.mag(),
          h: v.heading()
        }
        if(v.mag()<near){
          near=v.mag();
          nearest=i;
        }
      });
      if(isHalfInside){
        //order by heading, reverse
        farVerts.sort(function(a,b){
          return b.h-a.h;
        });
      } else {
        farVerts.splice(nearest,1);
        farVerts.sort(function(a,b){
          return b.h-a.h;
        });
      }
  };
  
  this.showBeam=function(){
    var intensity=1-nearV.mag()/(width*0.71);
    push();
    translate(c.x, c.y);
    if(startV && endV && nearV && farStartV && farEndV && farFarV){
      fill(50+100*lightArea+intensity*100,50);
      noStroke();
      beginShape();
      vertex(startV.x, startV.y);
      vertex(nearV.x, nearV.y);
      vertex(endV.x, endV.y);
      vertex(farEndV.x, farEndV.y);
      vertex(farFarV.x, farFarV.y);
      vertex(farStartV.x, farStartV.y);
      endShape(CLOSE);
    } else {
      // console.log("not");
    }
    pop();
  }
  
  this.showBeam2=function(){
    var intensity=1-pivot.mag()/(width*0.71);
    push();
    translate(c.x, c.y);
    fill(hCol,0,lightArea*50+intensity*50,intensity);
    noStroke();
    rect(x-w/2,y-h/2,w,h);
    beginShape();
    if(isInside){
      outVerts.forEach(function(ov){
        vertex(ov.x, ov.y);
      });
    } else {
      nearVerts.forEach(function(nv){
        vertex(nv.v.x, nv.v.y);
      });
      farVerts.forEach(function(fv,i){
        vertex(fv.v.x, fv.v.y);
      });
    }
    noStroke();
    fill(hCol,0,intensity*100,intensity/2);//lightArea*35+65
    endShape(CLOSE);
    pop();
  }
  
  this.findOuter=function(){
    startA=TWO_PI;
    endA=0;
    startV=null;
    endV=null;
    nearD=width*2;
    nearV=null;
    farD=0;
    farV=null;
    farStartV=null;
    farEndV=null;
    farFarV=null;
    verts.forEach(function(v){
      if(v.heading()<startA){
        startA=v.heading();
        startV=v;
        farStartV=v.copy().setMag(width*0.71);
      }
      if(v.heading()>endA){
        endA=v.heading();
        endV=v;
        farEndV=v.copy().setMag(width*0.71);
      }
      if(v.mag()<nearD){
        nearD=v.mag();
        nearV=v;
      }
      if(v.mag()>farD){
        farD=v.mag();
        farV=v;
        farFarV=v.copy().setMag(width*0.71);
      }
    });
  }
}
!
999px

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