two-point perspective

class Cube
{
  float y1, y2, y3, y4, x1, x2, x3, x4, y5, y6;
  float pt1, pt2, midpoint;
  float mX, mY;
  float amt;

  color light, darkLeft, darkRight;
  color left, right;

  Cube() {}

  Cube(float mouse_X, float mouse_Y, float amount, float point1, float point2, float midPoint)
  {
    amt = amount;
    mX = mouse_X;
    mY = mouse_Y;
    pt1 = point1;
    pt2 = point2;
    midpoint = midPoint;
  }

  void cubeMath()
  {
    y1 = lerp(0, mY, amt); //change this amount 0.8
    y2 = lerp(400, mY, amt);

    y3 = lerp(y1, midpoint, 0.3);
    y4 = lerp(y2, midpoint, 0.3);

    x1 = lerp(mX, pt1, 0.3);
    x2 = lerp(mX, pt2, 0.3);

    float XYdiff = lerp(x1, x2, 0.5);
    x3 = lerp(mX, XYdiff, 1.52);
    y5 = lerp(y1, midpoint, 0.46);
    y6 = lerp(y2, midpoint, 0.46);

    float diff = mX/2.35; //scale mouse to RGB range
    float diffDiff = 255 - diff;

    //println(diff + " " + diffDiff);

    darkLeft = color(diff);
    light = color(255);
    left = lerpColor(darkLeft, light, 0.5);

    darkRight = color(diffDiff);
    right = lerpColor(darkRight, light, 0.5);
  }

  void display()
  {

    stroke(200);
    strokeWeight(0.5);

    line(x1, 0, x1, height);
    line(x2, 0, x2, height);
    line(0, y1, 600, y1);
    line(0, y2, 600, y2);

    line(0, y5, 600, y5);
    line(0, y6, 600, y6);

    //front
    line(mX, 0, mX, height);
    line(x3, 0, x3, height);

    stroke(0);
    strokeWeight(1);

    //left
    line(pt1, midpoint, mX, y1);
    line(pt1, midpoint, mX, y2);

    //right
    line(pt2, midpoint, mX, y1);
    line(pt2, midpoint, mX, y2);

    //top
    line(pt1, midpoint, x2, y3);
    line(pt2, midpoint, x1, y3);

    //bottom
    line(pt1, midpoint, x2, y4);
    line(pt2, midpoint, x1, y4);

    stroke(255, 0, 0);
    strokeWeight(1);
    line(mX, y1, mX, y2);

    fill(right, 150);

    //TOP Counter clockwise
    beginShape();
    vertex(x1, y3);
    vertex(mX, y1);
    vertex(x2, y3);
    vertex(x3, y5);
    vertex(x1, y3);
    endShape();

    fill(left, 150);

    //BOTTOM Clockwise
    beginShape();
    vertex(x1, y4);
    vertex(mX, y2);
     vertex(x2, y4);
    vertex(x3, y6);
    vertex(x1, y4);
    endShape();

    line(x3, y5, x3, y6);

    //LEFT SIDE Counter clockwise
    beginShape();
    vertex(mX, y1);
    vertex(x1, y3);
    vertex(x1, y4);
    vertex(mX, y2);
    vertex(mX, y1);
    endShape();

    fill(right, 100);

    //RIGHT SIDE Clockwise
    beginShape();
    vertex(mX, y1);
    vertex(x2, y3);
    vertex(x2, y4);
    vertex(mX, y2);
    vertex(mX, y1);
    endShape();

  fill(0);
  /*
//  //Clockwise
  text(int(x1) + ", " + int(y3), x1, y3); //point 1
  text(int(x2) + ", " + int(y3), x2, y3); //point 2
  text(int(x2) + ", " + int(y4), x2, y4); //point 3
  text(int(x1) + ", " + int(y4), x1, y4); //point 4
//
  text(mX + ", " + int(y1), mX, y1);
  text(mX + ", " + int(y2), mX, y2);*/
  }
}

Cube cube;
PFont font;
float mX, mY;
float pt1, pt2;
float amt;
float midpoint;

void setup()
{
  size(600, 600);
  smooth();
  //String[] fontlist = PFont.list();
  //println(fontlist);
  amt = 1.4;
  pt1 = 3;
  pt2 = 597;
  midpoint = 300;
}

void draw()
{
  background(235, 255, 255, 255);
  fill(0);
  text("Two Point Perspective", 9, 20);
  fill(100);
  text("Drag the points to change width", 9, 40);
  text("Use the UP and DOWN arrows to change height", 9, 60);

  mX = mouseX;
  mY = mouseY;
  println(mouseX + " " + mouseY);

  fill(255,0,0);
  stroke(0);
  strokeWeight(1);

  line(0, midpoint, 600, midpoint); //horizon line

  ellipse(pt1, midpoint, 6, 6);
  ellipse(pt2, midpoint, 6, 6);

  cube = new Cube(mX, mY, amt, pt1, pt2, midpoint);
  cube.cubeMath();
  cube.display();

  fill(0);
  if(pt1 < 250)
  {
    text(pt1 + ", " + midpoint, pt1, midpoint-10);
  }
  if(pt1 > 250)
  {
    text(pt1 + ", " + midpoint, pt1-50, midpoint-10);
  }

  if(pt2 > 550)
  {
    text(pt2 + ", " + midpoint, pt2-55, midpoint-10);
  }
  if(pt2 < 550)
  {
    text(pt2 + ", " + midpoint, pt2, midpoint-10);
  }

}

void mouseDragged()
{
  if((mX > pt1-10) && (mX < (pt1+10)) && (mY > midpoint-10) && (mY < midpoint+10))
  {
    pt1 = mouseX;

    if(pt1 < 3)
    {
      pt1 = 3;
    }
    if(pt1 > 294)
    {
      pt1 = 294;
    }
  }

  if((mX > pt2-10) && (mX < (pt2+10)) && (mY > midpoint-10) && (mY < midpoint+10))
  {
    pt2 = mouseX;

    if(pt2 > 597)
    {
      pt2 = 597;
    }
    if(pt2 < 306)
    {
      pt2 = 306;
    }
  }
}

void keyReleased()
{
  if(keyCode == UP)
  {
    amt = amt + 0.1;
    if(amt > 2.0)
    {
      amt = 2.0;
    }
  }

  if(keyCode == DOWN)
  {
    amt = amt - 0.1;
    if(amt < 1.0)
    {
      amt = 1.0;
    }
  }

  println(amt);
}