Struct PietBackend

pub struct PietBackend<'a, 'b> {
    pub size: (u32, u32),
    pub render_ctx: &'a mut Piet<'b>,
}

The piet backend.

Note that the size of the piet context has to be specified here.

Fields

size: (u32, u32)

render_ctx: &'a mut Piet<'b>

Trait Implementations

impl<'a, 'b> Debug for PietBackend<'a, 'b>

fn fmt(&self, fmt: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<'a, 'b> DrawingBackend for PietBackend<'a, 'b>

type ErrorType = Error

The error type reported by the backend

fn get_size(&self) -> (u32, u32)

Get the dimension of the drawing backend in pixels

fn ensure_prepared(&mut self) -> Result<(), DrawingErrorKind<Self::ErrorType>>

Ensure the backend is ready to draw

fn present(&mut self) -> Result<(), DrawingErrorKind<Self::ErrorType>>

Finalize the drawing step and present all the changes. This is used as the real-time rendering support. The backend may implement in the following way, when ensure_prepared is called it checks if it needs a fresh buffer and present is called rendering all the pending changes on the screen.

fn draw_pixel( &mut self, point: BackendCoord, color: BackendColor, ) -> Result<(), DrawingErrorKind<Self::ErrorType>>

Draw a pixel on the drawing backend

fn draw_line<S: BackendStyle>( &mut self, from: BackendCoord, to: BackendCoord, style: &S, ) -> Result<(), DrawingErrorKind<Self::ErrorType>>

Draw a line on the drawing backend

fn draw_rect<S: BackendStyle>( &mut self, upper_left: BackendCoord, bottom_right: BackendCoord, style: &S, fill: bool, ) -> Result<(), DrawingErrorKind<Self::ErrorType>>

Draw a rectangle on the drawing backend

fn draw_path<S: BackendStyle, I: IntoIterator<Item = BackendCoord>>( &mut self, path: I, style: &S, ) -> Result<(), DrawingErrorKind<Self::ErrorType>>

Draw a path on the drawing backend

fn draw_circle<S: BackendStyle>( &mut self, center: BackendCoord, radius: u32, style: &S, fill: bool, ) -> Result<(), DrawingErrorKind<Self::ErrorType>>

Draw a circle on the drawing backend

fn fill_polygon<S: BackendStyle, I: IntoIterator<Item = BackendCoord>>( &mut self, vert: I, style: &S, ) -> Result<(), DrawingErrorKind<Self::ErrorType>>

fn draw_text<TStyle>( &mut self, text: &str, style: &TStyle, pos: (i32, i32), ) -> Result<(), DrawingErrorKind<Self::ErrorType>>

where TStyle: BackendTextStyle,

Draw a text on the drawing backend

fn estimate_text_size<TStyle>( &self, text: &str, style: &TStyle, ) -> Result<(u32, u32), DrawingErrorKind<Self::ErrorType>>

where TStyle: BackendTextStyle,

Estimate the size of the horizontal text if rendered on this backend. This is important because some of the backend may not have font ability. Thus this allows those backend reports proper value rather than ask the font rasterizer for that.

fn blit_bitmap( &mut self, pos: (i32, i32), _: (u32, u32), src: &[u8], ) -> Result<(), DrawingErrorKind<Self::ErrorType>>

Blit a bitmap on to the backend.