New feature improved automatic resizing

[Mohamed-Waiel-Shikfa]

Tries to address:

• Add "large canvas view" to Desktop CMU graphics #69

My approach:
if user wants cmu_graphics to handle resizing automatically for him,
then when screen resize:

• draw everything using the previous code at starting width and height size
• once the code gives back a pygame image scale that image to the new width and height
• if user want a same aspect ratio, scale to the smallest of x-scale and y-scale and offset the image so it is centred

I implemented the above faithfully but unfortunately it didn't work as I excepted and created a bug where the screen would constantly flicker.
I feel like there is a not so complicated way to fix this but I am unsure as to what it would be.
Once fixed this would be a great new feature to merge.

[linxuanm]

Hi! Are you still working on this? If not, do you mind if I continue off this PR? Thanks!

[Mohamed-Waiel-Shikfa]

I mean I don't mind but would like to stay in the loop.

My main issue is that I tried my best understanding the current drawing pipeline (from using pycairo to generate the image in the buffer and then passing that to pygame) but I am still not fully comfortable with it.

The way I tried implementing this feature until now is that if the user wants the canvas to resize automatically, we always draw to the starting size canvas with pycairo, then we transforme that to a pygame image and scale it by the (current width and height)/(starting width and height).

Does this make sense? Please let me know.