fix(sdl) update monitor texture pointer during resize

[ReimuNotMoe]

Texture pointer in monitor struct should be updated during SDL window resize, otherwise the old texture pointer will still be in use and result in invalid memory accesses.

[embeddedt]

This seems like a good fix to me. @mariotaku do you also agree?

[mariotaku]

Indeed. Not sure if we should do anything to old texture pointer though.

[ReimuNotMoe]

I want to add some more improvements to enable the end user to access SDL contexts, handle more SDL events, etc. These are necessary to:

• Specify window attribute, e.g. resizable, full screen, etc
• Specify renderer attribute, e.g. accelerated or not, vsync, etc
• Edit window title
• Change window size and position programmatically
• Resize window by mouse
• Adding IME support
• and many more

So is including SDL headers allowed in sdl_gpu.h?

[mariotaku]

IMO for advanced configuration, we can ask users to create their own window and renderer, and configure the disp driver by themselves. That how I did in my project: https://github.com/mariotaku/moonlight-tv/tree/main/app/lvgl

Handle display resize: https://github.com/mariotaku/moonlight-tv/blob/main/app/lvgl/lv_disp_drv_app.c IME support: https://github.com/mariotaku/moonlight-tv/blob/main/app/lvgl/lv_sdl_drv_key_input.c (CJK input is perfectly fine)

[ReimuNotMoe]

Thanks you for the suggestions. I won't make more changes. You can merge the existing two commits if you want.

[mariotaku]

LGTM!

[embeddedt]

Thank you; merged.