How could I make p5 work in a cartesian coordinate system?

Processing Coding Questions
1

I kind of get what I want but I still have problems using mouseX and mouseY, they don’t work propertly when I try to change it.

2

mouseX is how many pixels from the left edge the mouse is.

mouseY is how many pixels from the top edge the mouse is.

This is slightly different from a mathematical coordinate system, which usually has the positive Y direction going up from the bottom edge.

3

Yeah, I know, but I mean if I try to change it, how could I do for making those variables to work if they should in the system that I’m trying to use?

4

Just use (height-mouseY) instead of mouseY!

1 Like
5

Thank you for your answer!

7

A couple of things (be sure to comment one or the other) I have done in the past to modify what I plot to screen:

void setup() 
  {
  size(500, 500);
   }

void draw() 
  {
  background(0);
  
  //Method 1 This is one.
  //scale(1, -1);
  //translate(0, -height);
  
  for (int x=0; x<width; x++)
    {
    int y = x;
    y = height -y;  //Method 2 wherever there is a y. This is the other.
    strokeWeight(3);
    stroke(255, 255, 0);
    point(x, y);
    }  
}

:)