Add get_surface() for Window class

[yunline]

• Window.get_surface()
• Window.update_from_surface()
• Auto resize

import pygame
from pygame._sdl2 import video

pygame.init()

win = video.Window()
sf = win.get_surface()

sf.fill((255,0,0))
win.update_from_surface()

while 1:
    pygame.event.get()

Screenshot

[MyreMylar]

Overall this works great on windows OS and lets me use the window class to do familiar CPU blitting and drawing.

I agree that we should remove the list of rects overload from update_from_surface() however. The realistic speed ups from this functionality on most modern platforms are too minor, and too niche, to justify continuing it and the confusion it brings when users try to use it to speed up their games. They put a bunch of effort in to maintain an accurate list of sections of the screen that have changed this loop, only to then find that it in many cases it actually makes the program run slower because they have more than 15 or so moving objects in their application and the per-rectangle-cost of updating has exceeded the saving from the reduced area updated.

See #2514 for more discussion.

[ankith26]

Just commenting because I feel this change could be independent of this PR. I think it could fix another one of those init+quit+init issues.

But I would prefer moving this to the display specific init function instead, instead of messing with base.c. The diff would also be much less I reckon

[ankith26]

My bad, I assumed the changes were happening in display.c but I now see they are in window.c. My suggestion would still be along similar lines, create an "init-quit hook" (see what display.c does) for window, and set/unset this filter from there.

[ankith26]

Yes these hooks look good, but I think they should be called from the display init/quit hook instead of the base pygame init/quit function (like how event and time are handled right now). This is so that if someone only does pygame.display.init() instead of the full pygame.init() we would still want the window hooks to run, as they are related

[yunline]

fixed

[Starbuck5]

Let's get this in. Thanks yunline!

Note from testing: window resize doesn't work properly when using a borrowed window--

import pygame
from pygame._sdl2 import Window

pygame.init()

screen = pygame.display.set_mode((500,500))
window = Window.from_display_module()

window_screen = window.get_surface()
running = True
while running:
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            running = False

        if event.type == pygame.KEYDOWN:
            if event.key == pygame.K_1:
                window.size = (500,500)
            if event.key == pygame.K_2:
                window.size = (700,700)

    window.update_from_surface()
pygame.quit()

After this is merged I have several things I'd like to do myself on this. I want to change update_from_surface() to flip(), I'd like to write some things in the docs about how it's analogous to set_mode and flip(), and I'd like to add a standalone window software rendering example.

So even though there is still improvement to we can make to this API, the way forward is not to delay this PR any longer, but to get it to main.

The way forward on this is getting this PR merged. @yunline I'm leaving it to you to merge-- I think some of the commits could be squashed down, but it's up to your discretion.