Usability methods for RenderTargets and image handles

[torsteingrindvik]

Objective

In my code I use a lot of images as render targets.
I'd like some convenience methods for working with this type.

Solution

• Allow .into() to construct a RenderTarget
• Add .as_image()

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Changelog

Added

• RenderTarget can be constructed via .into() on a Handle<Image>
• RenderTarget new method: as_image

[alice-i-cecile]

Not totally sold on having an infallible version here, but that's fine.

[torsteingrindvik]

Not totally sold on having an infallible version here, but that's fine.

I was on the fence myself but included it due to Bevy having several APIs which panic if user assumptions fail: get_resource vs resource, get_sub_app vs sub_app etc.

But it's not that important to have so let me know if you'd rather have me remove it.

[alice-i-cecile]

Yeah let's remove it. We tend to include them only in cases where it's a) very hard to accidentally panic b) the API is very high-traffic.

[torsteingrindvik]

Yeah let's remove it. We tend to include them only in cases where it's a) very hard to accidentally panic b) the API is very high-traffic.

That makes sense to me.
Changed it now

[thepackett]

Looks good to me.