fix: Skip some rendering logics when the viewport width or height is zero

[ShoyuVanilla]

Objective

• Fixes Minimizing window in the irradiance_volume example causes a crash #15285

Solution

winit sends resized to zero events when the window is minimized only on Windows OS(rust-windowing/winit#2015).
This makes updating window viewport size to (0, 0) and panicking when calculating aspect ratio.

So, just skip these kinds of events - resizing to (0, 0) when the window is minimized - on Windows OS

Idially, the camera extraction excludes the cameras whose target size width or height is zero here;

bevy/crates/bevy_render/src/camera/camera.rs

Lines 1060 to 1074 in 25bfa80

	if let (
	Some(URect {
	min: viewport_origin,
	..
	}),
	Some(viewport_size),
	Some(target_size),
	) = (
	camera.physical_viewport_rect(),
	camera.physical_viewport_size(),
	camera.physical_target_size(),
	) {
	if target_size.x == 0 || target_size.y == 0 {
	continue;
	}

but it seems that winit event loop sends resize events after extraction and before post update schedule, so they might panics before the extraction filters them out.

Alternatively, it might be possible to change event loop evaluating order or defer them to the right schedule but I'm afraid that it might cause some breaking changes, so just skip rendering logics for such windows and they will be all filtered out by the extractions on the next frame and thereafter.

Testing

Running the example in the original issue and minimizing causes panic, or just running tests/window/minimising.rs with cargo run --example minimising panics without this PR and doesn't panics with this PR.

I think that we should run it in CI on Windows OS btw

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[mockersf]

This works by hiding the problem.

Would it be possible to stop rendering when the render target is (0,0)? I think this was done in a few places already

[ShoyuVanilla]

This works by hiding the problem.

Would it be possible to stop rendering when the render target is (0,0)? I think this was done in a few places already

Okay, I'll look into this more

[ShoyuVanilla]

I've changed the approach

[bushrat011899]

Simple change well executed!

[tychedelia]

This might be off base or incur other kinds of sneaky bugs in the future, but I'm wondering if the methods on camera shouldn't check and return None in the case of (0,0), is this ever a valid size that code would want to support? I guess None is different than zero sized in the context of viewports, but for some reason I feel like we should try for a fix upstream rather than hard coding the 0 checks everywhere (which will surely also be forgotten in the future).

[ShoyuVanilla]

This might be off base or incur other kinds of sneaky bugs in the future, but I'm wondering if the methods on camera shouldn't check and return None in the case of (0,0), is this ever a valid size that code would want to support? I guess None is different than zero sized in the context of viewports, but for some reason I feel like we should try for a fix upstream rather than hard coding the 0 checks everywhere (which will surely also be forgotten in the future).

On the None for viewport (0, 0), I think that it seems reasonable to do so, but I'm not so confident about it because I'm quite new to bevy 😅
In general, I agree with that the issues caused from the upstreams should be fixed from the upstream.
But I think that it's also worthwhile to handle zero-sized viewport because it might be happen by window resizing or something, other than minimizing on Windows OS. (Of course it should be better than the current hard coded way)