let shaderBG;

​

let pointBG;

​

let secs;

​

let triangles = [];

let normals = [];

​

function preload(){

  theShader = loadShader('shader.vert','shader.frag');

}

​

function setup() {

  createCanvas(400, 400);

  shaderBG = createGraphics(width,height,WEBGL);

  pointBG = createGraphics(width,height);

  pointBG.background(255);

  const rast=30;

  for(let i=rast/2;i<width;i+=rast){

    for(let j=rast/2;j<height;j+=rast){

      pointBG.point(i,j);

    }

  }

  for(let i=0;i<30;i++){

    addTriangle(0,80);

  }

  noCursor();

  // shaderBG.noStroke();

}

​

function draw() {

  secs = millis()*0.001;

  if(mouseIsPressed){

    addTriangle(1,150);

  }

  image(pointBG,0,0,width,height);

  shaderBG.push();

  shaderBG.shader(theShader);

  theShader.setUniform('time', secs);

  shaderBG.background(255,0);

  shaderBG.rotateY(secs);

  shaderBG.rotateX(secs*0.5);

  shaderBG.translate(sin(secs)*50,cos(secs*1.1)*30)

  // shaderBG.sphere(120,24,24);

  shaderBG.beginShape(TRIANGLES);

  for(let i=0;i<triangles.length;i++){

    shaderBG.normal(normals[i])

    for(let j=0;j<3;j++){

      shaderBG.vertex(triangles[i][j].x,

                      triangles[i][j].y,

                      triangles[i][j].z);

    }

  }

  shaderBG.endShape();

​

  image(shaderBG,0,0,width,height)

  shaderBG.pop();

  rect(mouseX-12.5*cos(secs), mouseY-12.5*sin(secs*1.2), 25*cos(secs), 25*sin(secs*1.2))

}

​

​

function addTriangle(method,scalar){

  if(method==0){

    //pure random triangles

    triangles.push(

      [

        p5.Vector.random3D().mult(scalar),

        p5.Vector.random3D().mult(scalar),

        p5.Vector.random3D().mult(scalar)

      ]    

    )

  }

  if(method==1){

    //along a sphere

    let center = p5.Vector.random3D().mult(2);

    triangles.push(

      [

        p5.Vector.add(center, p5.Vector.random3D()).normalize().mult(scalar),

        p5.Vector.add(center, p5.Vector.random3D()).normalize().mult(scalar),

        p5.Vector.add(center, p5.Vector.random3D()).normalize().mult(scalar)

      ]    

    )

    normals.push(center.copy());

  }

    // theres smth wrong with my normal math lmao

    // ah motherfucker of course they can point either way depending on which one i start bc its the cross product yuck. so in this case i would want one the one pointing away fromthe center but like that shitis gona vary from case to case so idk

    let u = p5.Vector.sub(triangles[triangles.length-1][1], triangles[triangles.length-1][0]);

    let v = p5.Vector.sub(triangles[triangles.length-1][2], triangles[triangles.length-1][0]);

​

    normals.push(createVector(

      u.y*v.z - u.z*v.y,

      u.z*v.x - u.x*v.z,

      u.x*v.y - u.y*v.x).normalize()

                );

}

​