Outside the canvas

When I'm placing things randomly on the canvas. How can I make shore that nothing gets placed outside the screen?

I'm pretty shore there is a silly simple solution to this that just are to simple to think of.

It depends on the type of shape you're placing, but for simple rects or ovals, this will do:

size(200, 200)
 
for i in range(100):
    fill(random(), 0, 0)
    rect(random(WIDTH-30), random(HEIGHT-30), 30, 30)

As an alternative, if you want to use any shape, and compare it to any other shape, consider the following approach. Here, we use boolean operations to check if paths don't intersect eachother. This is the most generic and powerful way to do shape-in-shape placement.

size(200, 200)
 
canvas_rect = rect(0, 0, WIDTH, HEIGHT, draw=False)
 
path = textpath("A", 10, 10)
path.fit(0, 0, WIDTH, HEIGHT)
 
# As an alternative, you can use any shape, such as this oval.
# Comment out this line to use an oval instead of a letter.
# path = oval(0,0,WIDTH,HEIGHT, draw=False)
 
# We need to check if the shape falls fully within the bounds
# of the shape. To do that, we check if it *doesn't* intersect
# with the negative of this shape. So we take a shape as big as
# the canvas, and punch our path out of that, resulting in the
# negative shape.
negative = canvas_rect.difference(path)
 
# Now we place shapes by brute-force. We want 200 shapes,
# so we run a loop that doesn't finish until we have 200 shapes.
shapes = []
while len(shapes) < 200:
    # Place a random shape somewhere. This can be any shape.
    # Just don't make it too big, or it will never fit,
    # resulting in an infinite loop.
    r = rect(random(WIDTH), random(HEIGHT), 4, 4, draw=False)
    # If this path doesn't intersect with the negative of the 
    # original path, append it to the list of shapes.
    if not negative.intersects(r):
        shapes.append(r)
 
# Now, draw each of the shapes.
for shape in shapes:
    fill(random(), 0, 0)
    drawpath(shape)

Nice! Thank you both of you :)