Move Msaa to a component, instead of a resource

[JMS55]

No description provided.

[alice-i-cecile]

I take it this should be a component on individual cameras?

[JMS55]

Yes, aligning with how all the other rendering stuff is now per-camera.

[mockersf]

from #7215, msaa configuration should not be on the camera but on the window

[Aceeri]

Also ideally it shouldn't be another component, but just added to the Window component here:

bevy/crates/bevy_window/src/window.rs

Lines 96 to 163 in 884ebbf

	pub struct Window {
	/// The cursor of this window.
	pub cursor: Cursor,
	/// What presentation mode to give the window.
	pub present_mode: PresentMode,
	/// Which fullscreen or windowing mode should be used?
	pub mode: WindowMode,
	/// Where the window should be placed.
	pub position: WindowPosition,
	/// What resolution the window should have.
	pub resolution: WindowResolution,
	/// Stores the title of the window.
	pub title: String,
	/// How the alpha channel of textures should be handled while compositing.
	pub composite_alpha_mode: CompositeAlphaMode,
	/// Which size limits to give the window.
	pub resize_constraints: WindowResizeConstraints,
	/// Should the window be resizable?
	///
	/// Note: This does not stop the program from fullscreening/setting
	/// the size programmatically.
	pub resizable: bool,
	/// Should the window have decorations enabled?
	///
	/// (Decorations are the minimize, maximize, and close buttons on desktop apps)
	///
	// ## Platform-specific
	//
	// **`iOS`**, **`Android`**, and the **`Web`** do not have decorations.
	pub decorations: bool,
	/// Should the window be transparent?
	///
	/// Defines whether the background of the window should be transparent.
	///
	/// ## Platform-specific
	/// - iOS / Android / Web: Unsupported.
	/// - macOS X: Not working as expected.
	/// - Windows 11: Not working as expected
	/// macOS X transparent works with winit out of the box, so this issue might be related to: <https://github.com/gfx-rs/wgpu/issues/687>
	/// Windows 11 is related to <https://github.com/rust-windowing/winit/issues/2082>
	pub transparent: bool,
	/// Should the window start focused?
	pub focused: bool,
	/// Should the window always be on top of other windows?
	///
	/// ## Platform-specific
	///
	/// - iOS / Android / Web / Wayland: Unsupported.
	pub always_on_top: bool,
	/// The "html canvas" element selector.
	///
	/// If set, this selector will be used to find a matching html canvas element,
	/// rather than creating a new one.
	/// Uses the [CSS selector format](https://developer.mozilla.org/en-US/docs/Web/API/Document/querySelector).
	///
	/// This value has no effect on non-web platforms.
	pub canvas: Option<String>,
	/// Whether or not to fit the canvas element's size to its parent element's size.
	///
	/// **Warning**: this will not behave as expected for parents that set their size according to the size of their
	/// children. This creates a "feedback loop" that will result in the canvas growing on each resize. When using this
	/// feature, ensure the parent's size is not affected by its children.
	///
	/// This value has no effect on non-web platforms.
	pub fit_canvas_to_parent: bool,
	/// Stores internal state that isn't directly accessible.
	pub internal: InternalWindowState,
	}

[lain-dono]

A real world example where MSAA can be used in the camera, but not in the whole window:

The portraits at the top left are a separate realtime scene. Sometimes you may want a better quality for them than the world map.

Using separate MSAA settings for each camera makes it easier to reimplement something like this in bevy.

[alice-i-cecile]

@JMS55 can you polish up the description and migration guide for this?