Trait ItemRenderer

pub trait ItemRenderer {
    // Required methods
    fn draw_rectangle(
        &mut self,
        rect: Pin<&Rectangle>,
        _self_rc: &ItemRc,
        _size: LogicalSize,
    );
    fn draw_border_rectangle(
        &mut self,
        rect: Pin<&dyn RenderBorderRectangle>,
        _self_rc: &ItemRc,
        _size: LogicalSize,
        _cache: &CachedRenderingData,
    );
    fn draw_image(
        &mut self,
        image: Pin<&dyn RenderImage>,
        _self_rc: &ItemRc,
        _size: LogicalSize,
        _cache: &CachedRenderingData,
    );
    fn draw_text(
        &mut self,
        text: Pin<&dyn RenderText>,
        _self_rc: &ItemRc,
        _size: LogicalSize,
        _cache: &CachedRenderingData,
    );
    fn draw_text_input(
        &mut self,
        text_input: Pin<&TextInput>,
        _self_rc: &ItemRc,
        _size: LogicalSize,
    );
    fn draw_path(
        &mut self,
        path: Pin<&Path>,
        _self_rc: &ItemRc,
        _size: LogicalSize,
    );
    fn draw_box_shadow(
        &mut self,
        box_shadow: Pin<&BoxShadow>,
        _self_rc: &ItemRc,
        _size: LogicalSize,
    );
    fn combine_clip(
        &mut self,
        rect: LogicalRect,
        radius: LogicalBorderRadius,
        border_width: LogicalLength,
    ) -> bool;
    fn get_current_clip(&self) -> LogicalRect;
    fn translate(&mut self, distance: LogicalVector);
    fn rotate(&mut self, angle_in_degrees: f32);
    fn apply_opacity(&mut self, opacity: f32);
    fn save_state(&mut self);
    fn restore_state(&mut self);
    fn scale_factor(&self) -> f32;
    fn draw_cached_pixmap(
        &mut self,
        item_cache: &ItemRc,
        update_fn: &dyn Fn(&mut dyn FnMut(u32, u32, &[u8])),
    );
    fn draw_string(&mut self, string: &str, color: Color);
    fn draw_image_direct(&mut self, image: Image);
    fn window(&self) -> &WindowInner;
    fn as_any(&mut self) -> Option<&mut dyn Any>;

    // Provided methods
    fn visit_opacity(
        &mut self,
        opacity_item: Pin<&Opacity>,
        _self_rc: &ItemRc,
        _size: LogicalSize,
    ) -> RenderingResult { ... }
    fn visit_layer(
        &mut self,
        _layer_item: Pin<&Layer>,
        _self_rc: &ItemRc,
        _size: LogicalSize,
    ) -> RenderingResult { ... }
    fn visit_clip(
        &mut self,
        clip_item: Pin<&Clip>,
        item_rc: &ItemRc,
        _size: LogicalSize,
    ) -> RenderingResult { ... }
    fn translation(&self) -> LogicalVector { ... }
    fn draw_rect(&mut self, _size: LogicalSize, _brush: Brush) { ... }
    fn filter_item(&mut self, item: &ItemRc) -> (bool, LogicalRect) { ... }
    fn metrics(&self) -> RenderingMetrics { ... }
}

Trait used to render each items.

The item needs to be rendered relative to its (x,y) position. For example, draw_rectangle should draw a rectangle in (pos.x + rect.x, pos.y + rect.y)

Required Methods

fn draw_rectangle( &mut self, rect: Pin<&Rectangle>, _self_rc: &ItemRc, _size: LogicalSize, )

fn draw_border_rectangle( &mut self, rect: Pin<&dyn RenderBorderRectangle>, _self_rc: &ItemRc, _size: LogicalSize, _cache: &CachedRenderingData, )

fn draw_image( &mut self, image: Pin<&dyn RenderImage>, _self_rc: &ItemRc, _size: LogicalSize, _cache: &CachedRenderingData, )

fn draw_text( &mut self, text: Pin<&dyn RenderText>, _self_rc: &ItemRc, _size: LogicalSize, _cache: &CachedRenderingData, )

fn draw_text_input( &mut self, text_input: Pin<&TextInput>, _self_rc: &ItemRc, _size: LogicalSize, )

fn draw_path(&mut self, path: Pin<&Path>, _self_rc: &ItemRc, _size: LogicalSize)

fn draw_box_shadow( &mut self, box_shadow: Pin<&BoxShadow>, _self_rc: &ItemRc, _size: LogicalSize, )

fn combine_clip( &mut self, rect: LogicalRect, radius: LogicalBorderRadius, border_width: LogicalLength, ) -> bool

Clip the further call until restore_state. radius/border_width can be used for border rectangle clip. (FIXME: consider removing radius/border_width and have another function that take a path instead) Returns a boolean indicating the state of the new clip region: true if the clip region covers an area; false if the clip region is empty.

fn get_current_clip(&self) -> LogicalRect

Get the current clip bounding box in the current transformed coordinate.

fn translate(&mut self, distance: LogicalVector)

fn rotate(&mut self, angle_in_degrees: f32)

fn apply_opacity(&mut self, opacity: f32)

Apply the opacity (between 0 and 1) for all following items until the next call to restore_state.

fn save_state(&mut self)

fn restore_state(&mut self)

fn scale_factor(&self) -> f32

Returns the scale factor

fn draw_cached_pixmap( &mut self, item_cache: &ItemRc, update_fn: &dyn Fn(&mut dyn FnMut(u32, u32, &[u8])), )

Draw a pixmap in position indicated by the pos. The pixmap will be taken from cache if the cache is valid, otherwise, update_fn will be called with a callback that need to be called once with fn (width, height, data) where data are the RGBA premultiplied pixel values

fn draw_string(&mut self, string: &str, color: Color)

Draw the given string with the specified color at current (0, 0) with the default font. Mainly used by the performance counter overlay.

fn draw_image_direct(&mut self, image: Image)

fn window(&self) -> &WindowInner

fn as_any(&mut self) -> Option<&mut dyn Any>

Return the internal renderer

Provided Methods

fn visit_opacity( &mut self, opacity_item: Pin<&Opacity>, _self_rc: &ItemRc, _size: LogicalSize, ) -> RenderingResult

fn visit_layer( &mut self, _layer_item: Pin<&Layer>, _self_rc: &ItemRc, _size: LogicalSize, ) -> RenderingResult

fn visit_clip( &mut self, clip_item: Pin<&Clip>, item_rc: &ItemRc, _size: LogicalSize, ) -> RenderingResult

fn translation(&self) -> LogicalVector

fn draw_rect(&mut self, _size: LogicalSize, _brush: Brush)

Fills a rectangle at (0,0) with the given size. This is used for example by the Skia renderer to handle window backgrounds with a brush (gradient).

fn filter_item(&mut self, item: &ItemRc) -> (bool, LogicalRect)

This is called before it is being rendered (before the draw_* function). Returns

• if the item needs to be drawn (false means it is clipped or doesn’t need to be drawn)
• the geometry of the item

fn metrics(&self) -> RenderingMetrics

Returns any rendering metrics collecting since the creation of the renderer (typically per frame)

Implementors

impl<'a, T: ItemRenderer> ItemRenderer for PartialRenderer<'a, T>