spawning random objects

prestige141

hello, i have been trying to spawn ellipse below the y axis on processing but i do not know how to use "random" this is what i have, can someone help/correct my work?

void draw() {
 background(255);
  if(random(0,100)<10){
    fill(229,28,35); //Red balloon
  ellipse(width/2,530-a,30,30);
  a= a- 1;
  }

PhiLho

I have a problem of vocabulary. How do you spawn one ellipse? Do you mean to draw it multiple times? What do you call y axis, and how do you go below it?

random() allows to generate a random number between two bounds, you can use it to generate random coordinates in a given range. You can also use a for loop to draw several ellipses, if that's what you want to do.

prestige141

The size of my project is size(500,500) I am trying to spawn an ellipse with the coordinates out of the screen, below the y axis...ex:

int a= 5
ellipse(width/2,530-a,30,30); //this makes the ellipse rise(on the y axis)
a= a- 1;

I want to make the ellipse spawn at random below the y axis, and anywhere on the x axis.

koogs

use another variable (x?) for the first argument of ellipse().

set it to a random number between, roughly, 0 and width. see random() in the reference.

prestige141

ok thanks i was able to set up random spawn now. What would i have to set up for the ellipse to be deleted if it's clicked on when the mouse is over the ellipse?

PhiLho

Ah, OK. The Y axis is the vertical one, so I suppose you meant beyond the highest Y value. And spawning was in the sense of rising, appearing gradually.

To detect a mouse click within the ellipse (a circle, actually), you have to create the mouseClicked() function, and there, to check if the dist() between mouseX / mouseY coordinates and the center of the circle are below the radius of the circle.

prestige141

I set up my mouseClicked but it is not working.

void mouseClicked() {
  if (mouse) {
    ((mouseX && mouseY-7) == (x && 530+a));
  }

the second coordinates "x" and "530=a" represent the ellipse, what did i do wrong?

PhiLho

"what did i do wrong?"
Well, I fear that creating syntax isn't accepted by Processing... :-)

Again, try and explore a bit the examples in Processing, to get a feel how things work. There are a number of examples (File > Examples...) that handle mouse click on a circle.

Hint: you need the if keyword, and as said, the dist() function.