keep aspect ratio option for spriterenderer

[Shadowblitz16]

Summary

Add keep aspect ratio for sprite renderer
this would basically make sure the rect is always centered and and has the same size as the current texture frame.

Analysis

Pros

• we would no longer need to make a script to adjust the rect on the sprite renderer.

Cons

• none

Attachments

-Now

-What it could be

[SirePi]

Maybe it would make sense to add a method that sets a SpriteRenderer's Rect to the values obtained from the currently assigned Material/BatchInfo.

Something like a public void UseNativeSize(Alignment alignment) where Alignment is used to define the origin of the Rect.
Possibly add a button to call it from the editor as well, defaulting to Centered?

[Shadowblitz16]

idk though I do think that it being centered and the aspect ratio mode should be separate.