Question about a simple code using lines and rectangles

[JamesP]

Why is it that I have to use (100,40,400,210) to make the rectangle the same size as the lines? I would have thought I could use (100,40,500,250). It doesn’t make sense to me that 400, 210 is at the same spot as where my line ends but it is at 500, 250.

[Chrisir]

The reason is this

Line works with x1,y1 and x2,y2

rect works with x,y and w,h

Hence the difference

[JamesP]

Oh I understand now. Thank you!

[quark]

You can use the rectMode function to change how the parameters are interpreted, for instance rectMode(CORNERS) works with x1,y1 and x2,y2

void setup(){
  size(640, 480);
}

void draw(){
  background(200);
  rectMode(CORNERS);
  
  noStroke();
  fill(128,128,255);
  rect(100, 40, 500, 250);
  
  stroke(0);
  strokeWeight(5);
  line(100, 40, 500, 250);
  
  strokeWeight(3);
  line(500,40,100,250);
}

gives you

[JamesP]

Thank you! I see how that works now. I’m literally just starting as you can tell.

[quark]

@JamesP

I’m literally just starting

Every expert starts as a novice, enjoy the journey