pub trait Context<B: Backend> {
// Required methods
fn pixel_format(&self) -> PixelFormat;
fn path_builder(&self) -> Option<B::PathBuilder>;
fn raster_builder(&self) -> Option<B::RasterBuilder>;
fn new_image(&mut self, size: Size2D<u32>) -> B::Image;
fn new_image_from_png<R: Read>(
&mut self,
reader: &mut Reader<R>,
) -> Result<B::Image, Error>;
fn get_image(&mut self, image_index: u32) -> B::Image;
fn get_current_image(&mut self, context: &ViewAssistantContext) -> B::Image;
fn render_with_clip(
&mut self,
composition: &mut B::Composition,
clip: Rect<u32>,
image: B::Image,
ext: &RenderExt<B>,
);
// Provided method
fn render(
&mut self,
composition: &mut B::Composition,
clip: Option<Rect<u32>>,
image: B::Image,
ext: &RenderExt<B>,
) { ... }
}
Expand description
Rendering context and API start point.
Required Methods§
Sourcefn pixel_format(&self) -> PixelFormat
fn pixel_format(&self) -> PixelFormat
Returns the context’s pixel format.
Sourcefn path_builder(&self) -> Option<B::PathBuilder>
fn path_builder(&self) -> Option<B::PathBuilder>
Optionally returns a PathBuilder
. May return None
of old builder is still alive.
Sourcefn raster_builder(&self) -> Option<B::RasterBuilder>
fn raster_builder(&self) -> Option<B::RasterBuilder>
Optionally returns a RasterBuilder
. May return None
of old builder is still alive.
Sourcefn new_image_from_png<R: Read>(
&mut self,
reader: &mut Reader<R>,
) -> Result<B::Image, Error>
fn new_image_from_png<R: Read>( &mut self, reader: &mut Reader<R>, ) -> Result<B::Image, Error>
Creates a new image from PNG reader
.
Sourcefn get_current_image(&mut self, context: &ViewAssistantContext) -> B::Image
fn get_current_image(&mut self, context: &ViewAssistantContext) -> B::Image
Returns the context
’s current image.
Sourcefn render_with_clip(
&mut self,
composition: &mut B::Composition,
clip: Rect<u32>,
image: B::Image,
ext: &RenderExt<B>,
)
fn render_with_clip( &mut self, composition: &mut B::Composition, clip: Rect<u32>, image: B::Image, ext: &RenderExt<B>, )
Renders the composition with a clip to the image.
Provided Methods§
Dyn Compatibility§
This trait is not dyn compatible.
In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.