Struct Canvas 

pub struct Canvas { /* private fields */ }

Implementations

impl Canvas

pub fn new() -> Self

pub fn background(self, fill: impl Into<Fill>) -> Self

pub fn no_background(self) -> Self

pub fn focusable(self, focusable: bool) -> Self

pub fn capture(self, capturable: bool) -> Self

pub fn cursor(self, cursor: CursorIcon) -> Self

pub fn width(self, width: impl Into<Length>) -> Self

pub fn height(self, height: impl Into<Length>) -> Self

pub fn min_width(self, v: f32) -> Self

pub fn max_width(self, v: f32) -> Self

pub fn min_height(self, v: f32) -> Self

pub fn max_height(self, v: f32) -> Self

pub fn flex(self, weight: f32) -> Self

pub fn expand(self) -> Self

pub fn fill_width(self) -> Self

pub fn fill_height(self) -> Self

pub fn fill_size(self) -> Self

pub fn on_draw(self, draw: impl Fn(&mut Painter<'_, '_>) + 'static) -> Self

pub fn with_effect<E>( self, shader: E, content: impl Fn(&mut Painter<'_, '_>) + 'static, ) -> Self

where E: SequoiShader + Copy + 'static,

Replaces the canvas draw with content piped through shader.

content renders into an offscreen target and shader is drawn over the whole canvas with that target bound as its content input. The shader must be registered (see App::shader_type).

pub fn with_shader_pass<S>(self, pass: ShaderPass<S>) -> Self

where S: SequoiShader + Copy + 'static,

Replaces the canvas draw with a configured shader pass.

The pass draws over the canvas bounds unless ShaderPass::at was used. Missing registrations log a warning and skip the draw.

pub fn with_effect_pass<S>( self, pass: ShaderPass<S>, content: impl Fn(&mut Painter<'_, '_>) + 'static, ) -> Self

where S: SequoiShader + Copy + 'static,

Replaces the canvas draw with content piped through a configured pass.

The pass’s first declared texture is bound to the captured content unless the pass already binds it explicitly. Use this instead of with_effect when the effect has extra uniforms, a blend mode, or a UV window.

pub fn with_layer_effect<S>( self, pass: ShaderPass<S>, first: impl Fn(&mut Painter<'_, '_>) + 'static, second: impl Fn(&mut Painter<'_, '_>) + 'static, ) -> Self

where S: SequoiShader + Copy + 'static,

Captures two layers and feeds them to the pass in declaration order.

This is the convenient form of a transition or a two-input composite: the first shader texture receives first, the second receives second.

pub fn with_effect_chain( self, content: impl Fn(&mut Painter<'_, '_>) + 'static, chain: ShaderChain, ) -> Self

Pipes content through every pass in chain.

Intermediate results live in offscreen targets; the final pass draws into the canvas. A pass that is not registered is skipped and its input is forwarded, so an optional effect does not blank the layer.

pub fn with_mask( self, mask: impl Fn(&mut Painter<'_, '_>) + 'static, content: impl Fn(&mut Painter<'_, '_>) + 'static, ) -> Self

Replaces the canvas draw with content masked by mask.

Both closures render into their own offscreen target; the built-in apply_mask shader keeps the layer color and multiplies its alpha by the mask alpha.

pub fn on_pointer( self, handler: impl Fn(Point, &PointerEvent, &mut EventCtx<'_>) + 'static, ) -> Self

pub fn key( self, key: Key, modifiers: Modifiers, action: impl Fn() + 'static, ) -> Self

pub fn on_key(self, handler: impl Fn(&KeyEvent) -> bool + 'static) -> Self

pub fn track(self, track: impl Fn() + 'static) -> Self

pub fn clip(self, clip: bool) -> Self

pub fn allow_overflow(self, px: f32) -> Self

pub fn overflow_px(self, px: f32) -> Self

pub fn paint_overflow(&self) -> f32

pub fn grid(self, step: f32) -> Self

pub fn grid_colored(self, step: f32, color: Color) -> Self

pub fn axes(self) -> Self

pub fn axes_colored(self, color: Color) -> Self

pub fn snap_every(self, step: f32) -> Self

pub fn snap_step(&self) -> Option<f32>

pub fn snap_value(&self, value: f32) -> f32

pub fn camera(self, pos: Vec2, zoom: f32) -> Self

pub fn no_camera(self) -> Self

pub fn camera_value(&self) -> Option<Camera>

pub fn background_fill(&self) -> Option<&Fill>

pub fn is_focusable(&self) -> bool

pub fn cursor_icon_value(&self) -> CursorIcon

pub fn binding_count(&self) -> usize

pub fn world_to_local(world: Point, cam: Vec2, zoom: f32) -> Point

pub fn local_to_world(local: Point, cam: Vec2, zoom: f32) -> Point

pub fn view_bounds(size: Size, cam: Vec2, zoom: f32) -> Rect

pub fn fit_view(content: Rect, size: Size, padding: f32) -> (Vec2, f32)

pub fn snap(value: f32, step: f32) -> f32

pub fn snap_point(p: Point, step: f32) -> Point

pub fn lod_banded(zoom: f32, breaks: &[f32]) -> usize

pub fn show_detail(zoom: f32, world: f32, min_px: f32) -> bool

pub fn detail_alpha(zoom: f32, world: f32, min_px: f32, fade_px: f32) -> f32

Trait Implementations

impl Clone for Canvas

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Default for Canvas

fn default() -> Self

Returns the “default value” for a type.

impl View for Canvas

fn body(&self) -> impl View + 'static

fn clip_self(&self) -> bool

fn layout_style_ctx(&self, _rt: &Runtime, _el: ElementId) -> LayoutStyle

fn accessibility(&self) -> Option<Accessible>

fn arrange_override( &self, _rt: &Runtime, _el: ElementId, _rect: Rect, _ctx: &mut LayoutCtx<'_>, ) -> bool

fn clip_radius(&self) -> f32

fn paint_opacity(&self) -> Option<f32>

fn cache_layer(&self) -> bool

Allows the runtime to replay this element’s painted subtree from cache while its element revision and absolute paint context stay unchanged.

fn paint_opacity_ctx(&self, _rt: &Runtime, _el: ElementId) -> Option<f32>

fn paint_offset(&self) -> Vec2

fn paint_offset_ctx(&self, _rt: &Runtime, _el: ElementId) -> Vec2

fn paint_scale(&self) -> f32

fn paint_scale_ctx(&self, _rt: &Runtime, _el: ElementId) -> f32

fn paint_rotation(&self) -> f32

fn paint_rotation_ctx(&self, _rt: &Runtime, _el: ElementId) -> f32

fn foreground_filter(&self) -> Option<Filter>

fn captures_pointer_ctx(&self, _rt: &Runtime, _el: ElementId) -> bool

fn reuse_state(&self, _old: &Self)

fn hit_testable(&self) -> bool

fn test_id(&self) -> Option<String>

fn focus_trap(&self) -> bool

fn accepts_tab(&self) -> bool

fn accepts_text_input(&self) -> bool

Whether this view edits text when focused.

fn ime_caret_rect(&self) -> Option<Rect>

Caret rectangle in window coordinates, used to place the platform IME candidate window. Widgets with a text caret return the box the caret occupies; hosts fall back to the focused element’s bounds when this is None.

fn paint_foreground(&self, _ctx: &mut PaintCtx<'_>)

fn accepts_drop(&self, _payload: &DragPayload) -> bool

fn on_drag_over(&self, _pos: DropPosition, _ctx: &mut EventCtx<'_>)

fn on_drop(&self, _pos: DropPosition, _ctx: &mut EventCtx<'_>)

fn on_drag_start(&self, _ctx: &mut EventCtx<'_>)

fn on_drag_end(&self, _end: DragEnd, _ctx: &mut EventCtx<'_>)