Struct nannou::frame::Frame

pub struct Frame<'swap_chain> { /* fields omitted */ }

A Frame to which the user can draw graphics before it is presented to the display.

Frames are delivered to the user for drawing via the user's view function.

See the RawFrame docs for more details on how the implementation works under the hood. The Frame type differs in that rather than drawing directly to the swapchain image the user may draw to an intermediary linear sRGBA image. There are several advantages of drawing to an intermediary image.

Methods

impl<'swap_chain> Frame<'swap_chain>

pub const DEFAULT_MSAA_SAMPLES: u32

The default number of multisample anti-aliasing samples used if the window with which the Frame is associated supports it.

pub const TEXTURE_FORMAT: TextureFormat

The texture format used by the intermediary linear sRGBA image.

We use a high bit depth format in order to retain as much information as possible when converting from the linear representation to the swapchain format (normally a non-linear representation).

pub fn texture(&self) -> &Texture

The texture to which all graphics should be drawn this frame.

This is not the swapchain texture, but rather an intermediary linear sRGBA image. This intermediary image is used in order to:

• Ensure consistent MSAA resolve behaviour across platforms.
• Avoid the need for multiple implicit conversions to and from linear sRGBA for each graphics pipeline render pass that is used.
• Allow for the user's rendered image to persist between frames.

The exact format of the texture is equal to Frame::TEXTURE_FORMAT.

If the number of MSAA samples specified is greater than 1 (which it is by default if supported by the platform), this will be a multisampled texture. After the view function returns, this texture will be resolved to a non-multisampled linear sRGBA texture. After the texture has been resolved if necessary, it will then be used as a shader input within a graphics pipeline used to draw the swapchain texture.

pub fn texture_view(&self) -> &TextureView

A full view into the frame's texture.

See texture for details.

pub fn resolve_target(&self) -> Option<&TextureView>

Returns the resolve target texture in the case that MSAA is enabled.

pub fn texture_format(&self) -> TextureFormat

The color format of the Frame's intermediary linear sRGBA texture (equal to Frame::TEXTURE_FORMAT).

pub fn texture_msaa_samples(&self) -> u32

The number of MSAA samples of the Frame's intermediary linear sRGBA texture.

pub fn texture_size(&self) -> [u32; 2]

The size of the frame's texture in pixels.

pub fn color_attachment_descriptor(&self) -> RenderPassColorAttachmentDescriptor

Short-hand for constructing a wgpu::RenderPassColorAttachmentDescriptor for use within a render pass that targets this frame's texture. The returned descriptor's attachment will the same wgpu::TextureView returned by the Frame::texture method.

Note that this method will not perform any resolving. In the case that msaa_samples is greater than 1, a render pass will be automatically added after the view completes and before the texture is drawn to the swapchain.

pub fn clear<C>(&self, color: C) where
    C: IntoLinSrgba<f32>, 

Clear the texture with the given color.

pub fn submit(self)

Submit the frame to the GPU!

Note that you do not need to call this manually as submission will occur automatically when the Frame is dropped.

Before submission, the frame does the following:

• If the frame's intermediary linear sRGBA texture is multisampled, resolve it.
• Write the intermediary linear sRGBA image to the swap chain texture.

It can sometimes be useful to submit the Frame before view completes in order to read the frame's texture back to the CPU (e.g. for screen shots, recordings, etc).

Methods from Deref<Target = RawFrame<'swap_chain>>

pub fn command_encoder(&self) -> RefMut<CommandEncoder>

Access the command encoder in order to encode commands that will be submitted to the swap chain queue at the end of the call to view.

pub fn window_id(&self) -> Id

The Id of the window whose wgpu surface is associated with this frame.

pub fn rect(&self) -> Rect

A Rect representing the full surface of the frame.

The returned Rect is equivalent to the result of calling Window::rect on the window associated with this Frame.

pub fn nth(&self) -> u64

The nth frame for the associated window since the application started.

E.g. the first frame yielded will return 0, the second will return 1, and so on.

pub fn swap_chain_texture(&self) -> &TextureViewHandle

The swap chain texture that will be the target for drawing this frame.

pub fn texture_format(&self) -> TextureFormat

The texture format of the frame's swap chain texture.

pub fn device_queue_pair(&self) -> &Arc<DeviceQueuePair>

The device and queue on which the swap chain was created and which will be used to submit the RawFrame's encoded commands.

This refers to the same DeviceQueuePair as held by the window associated with this frame.

Trait Implementations

impl<'swap_chain> Deref for Frame<'swap_chain>

type Target = RawFrame<'swap_chain>

The resulting type after dereferencing.

fn deref(&self) -> &Self::Target

Dereferences the value.

impl<'swap_chain> Drop for Frame<'swap_chain>

fn drop(&mut self)

Executes the destructor for this type.