How to scale a list of 2D coordinates to a desired size

Question

I have a list of 2D coordinates that draw a shape, e.g. [{12, 14}, {22, 44}, {59, 33}, ...]

I'd like to be able to take this shape, and center it in a canvas of arbitrary size (let's say 400x400) and have it take as much space as possible.

I've figured out how to normalize the list so it's in the 0-1 range, but ended up being stuck there when trying to then scale it up to the desired size.

Any help would be appreciated!

Answer 1

Find minimal and maximal values for X and Y coordinates xmin, xmax, ymin, ymax

Calculate point cloud width and height, and middle coordinates

cw = xmax - xmin
ch = ymax - ymin
mx = (xmax + xmin) / 2
my = (ymax + ymin) / 2

Now find coefficient

if cw * canvas.height >= ch * canvas.width
   coeff = canvas.width / cw   
else
   coeff = canvas.height / ch  

Now get canvas center

centerx = canvas.width / 2 
centery = canvas.height / 2 

and apply the next transformation to every point (x,y):

screenx = centerx + coeff * (x - mx)
screeny = centery + coeff * (y - my)