diff options
Diffstat (limited to 'tiny_skia/src/backend.rs')
-rw-r--r-- | tiny_skia/src/backend.rs | 856 |
1 files changed, 856 insertions, 0 deletions
diff --git a/tiny_skia/src/backend.rs b/tiny_skia/src/backend.rs new file mode 100644 index 00000000..a8add70b --- /dev/null +++ b/tiny_skia/src/backend.rs @@ -0,0 +1,856 @@ +use crate::core::text; +use crate::core::Gradient; +use crate::core::{Background, Color, Font, Point, Rectangle, Size, Vector}; +use crate::graphics::backend; +use crate::graphics::{Damage, Viewport}; +use crate::primitive::{self, Primitive}; +use crate::Settings; + +use std::borrow::Cow; + +pub struct Backend { + default_font: Font, + default_text_size: f32, + text_pipeline: crate::text::Pipeline, + + #[cfg(feature = "image")] + raster_pipeline: crate::raster::Pipeline, + + #[cfg(feature = "svg")] + vector_pipeline: crate::vector::Pipeline, +} + +impl Backend { + pub fn new(settings: Settings) -> Self { + Self { + default_font: settings.default_font, + default_text_size: settings.default_text_size, + text_pipeline: crate::text::Pipeline::new(), + + #[cfg(feature = "image")] + raster_pipeline: crate::raster::Pipeline::new(), + + #[cfg(feature = "svg")] + vector_pipeline: crate::vector::Pipeline::new(), + } + } + + pub fn draw<T: AsRef<str>>( + &mut self, + pixels: &mut tiny_skia::PixmapMut<'_>, + clip_mask: &mut tiny_skia::Mask, + primitives: &[Primitive], + viewport: &Viewport, + damage: &[Rectangle], + background_color: Color, + overlay: &[T], + ) { + let physical_size = viewport.physical_size(); + let scale_factor = viewport.scale_factor() as f32; + + if !overlay.is_empty() { + let path = tiny_skia::PathBuilder::from_rect( + tiny_skia::Rect::from_xywh( + 0.0, + 0.0, + physical_size.width as f32, + physical_size.height as f32, + ) + .expect("Create damage rectangle"), + ); + + pixels.fill_path( + &path, + &tiny_skia::Paint { + shader: tiny_skia::Shader::SolidColor(into_color(Color { + a: 0.1, + ..background_color + })), + anti_alias: false, + ..Default::default() + }, + tiny_skia::FillRule::default(), + tiny_skia::Transform::identity(), + None, + ); + } + + for ®ion in damage { + let path = tiny_skia::PathBuilder::from_rect( + tiny_skia::Rect::from_xywh( + region.x, + region.y, + region.width, + region.height, + ) + .expect("Create damage rectangle"), + ); + + pixels.fill_path( + &path, + &tiny_skia::Paint { + shader: tiny_skia::Shader::SolidColor(into_color( + background_color, + )), + anti_alias: false, + blend_mode: tiny_skia::BlendMode::Source, + ..Default::default() + }, + tiny_skia::FillRule::default(), + tiny_skia::Transform::identity(), + None, + ); + + adjust_clip_mask(clip_mask, region); + + for primitive in primitives { + self.draw_primitive( + primitive, + pixels, + clip_mask, + region, + scale_factor, + Vector::ZERO, + ); + } + + if !overlay.is_empty() { + pixels.stroke_path( + &path, + &tiny_skia::Paint { + shader: tiny_skia::Shader::SolidColor(into_color( + Color::from_rgb(1.0, 0.0, 0.0), + )), + anti_alias: false, + ..tiny_skia::Paint::default() + }, + &tiny_skia::Stroke { + width: 1.0, + ..tiny_skia::Stroke::default() + }, + tiny_skia::Transform::identity(), + None, + ); + } + } + + self.text_pipeline.trim_cache(); + + #[cfg(feature = "image")] + self.raster_pipeline.trim_cache(); + + #[cfg(feature = "svg")] + self.vector_pipeline.trim_cache(); + } + + fn draw_primitive( + &mut self, + primitive: &Primitive, + pixels: &mut tiny_skia::PixmapMut<'_>, + clip_mask: &mut tiny_skia::Mask, + clip_bounds: Rectangle, + scale_factor: f32, + translation: Vector, + ) { + match primitive { + Primitive::Quad { + bounds, + background, + border_radius, + border_width, + border_color, + } => { + let physical_bounds = (*bounds + translation) * scale_factor; + + if !clip_bounds.intersects(&physical_bounds) { + return; + } + + let clip_mask = (!physical_bounds.is_within(&clip_bounds)) + .then_some(clip_mask as &_); + + let transform = tiny_skia::Transform::from_translate( + translation.x, + translation.y, + ) + .post_scale(scale_factor, scale_factor); + + // Make sure the border radius is not larger than the bounds + let border_width = border_width + .min(bounds.width / 2.0) + .min(bounds.height / 2.0); + + let mut fill_border_radius = *border_radius; + for radius in &mut fill_border_radius { + *radius = (*radius) + .min(bounds.width / 2.0) + .min(bounds.height / 2.0); + } + let path = rounded_rectangle(*bounds, fill_border_radius); + + pixels.fill_path( + &path, + &tiny_skia::Paint { + shader: match background { + Background::Color(color) => { + tiny_skia::Shader::SolidColor(into_color( + *color, + )) + } + Background::Gradient(Gradient::Linear(linear)) => { + let (start, end) = + linear.angle.to_distance(bounds); + + let stops: Vec<tiny_skia::GradientStop> = + linear + .stops + .into_iter() + .flatten() + .map(|stop| { + tiny_skia::GradientStop::new( + stop.offset, + tiny_skia::Color::from_rgba( + stop.color.b, + stop.color.g, + stop.color.r, + stop.color.a, + ) + .expect("Create color"), + ) + }) + .collect(); + + tiny_skia::LinearGradient::new( + tiny_skia::Point { + x: start.x, + y: start.y, + }, + tiny_skia::Point { x: end.x, y: end.y }, + if stops.is_empty() { + vec![tiny_skia::GradientStop::new( + 0.0, + tiny_skia::Color::BLACK, + )] + } else { + stops + }, + tiny_skia::SpreadMode::Pad, + tiny_skia::Transform::identity(), + ) + .expect("Create linear gradient") + } + }, + anti_alias: true, + ..tiny_skia::Paint::default() + }, + tiny_skia::FillRule::EvenOdd, + transform, + clip_mask, + ); + + if border_width > 0.0 { + // Border path is offset by half the border width + let border_bounds = Rectangle { + x: bounds.x + border_width / 2.0, + y: bounds.y + border_width / 2.0, + width: bounds.width - border_width, + height: bounds.height - border_width, + }; + + // Make sure the border radius is correct + let mut border_radius = *border_radius; + let mut is_simple_border = true; + + for radius in &mut border_radius { + *radius = if *radius == 0.0 { + // Path should handle this fine + 0.0 + } else if *radius > border_width / 2.0 { + *radius - border_width / 2.0 + } else { + is_simple_border = false; + 0.0 + } + .min(border_bounds.width / 2.0) + .min(border_bounds.height / 2.0); + } + + // Stroking a path works well in this case + if is_simple_border { + let border_path = + rounded_rectangle(border_bounds, border_radius); + + pixels.stroke_path( + &border_path, + &tiny_skia::Paint { + shader: tiny_skia::Shader::SolidColor( + into_color(*border_color), + ), + anti_alias: true, + ..tiny_skia::Paint::default() + }, + &tiny_skia::Stroke { + width: border_width, + ..tiny_skia::Stroke::default() + }, + transform, + clip_mask, + ); + } else { + // Draw corners that have too small border radii as having no border radius, + // but mask them with the rounded rectangle with the correct border radius. + let mut temp_pixmap = tiny_skia::Pixmap::new( + bounds.width as u32, + bounds.height as u32, + ) + .unwrap(); + + let mut quad_mask = tiny_skia::Mask::new( + bounds.width as u32, + bounds.height as u32, + ) + .unwrap(); + + let zero_bounds = Rectangle { + x: 0.0, + y: 0.0, + width: bounds.width, + height: bounds.height, + }; + let path = + rounded_rectangle(zero_bounds, fill_border_radius); + + quad_mask.fill_path( + &path, + tiny_skia::FillRule::EvenOdd, + true, + transform, + ); + let path_bounds = Rectangle { + x: border_width / 2.0, + y: border_width / 2.0, + width: bounds.width - border_width, + height: bounds.height - border_width, + }; + + let border_radius_path = + rounded_rectangle(path_bounds, border_radius); + + temp_pixmap.stroke_path( + &border_radius_path, + &tiny_skia::Paint { + shader: tiny_skia::Shader::SolidColor( + into_color(*border_color), + ), + anti_alias: true, + ..tiny_skia::Paint::default() + }, + &tiny_skia::Stroke { + width: border_width, + ..tiny_skia::Stroke::default() + }, + transform, + Some(&quad_mask), + ); + + pixels.draw_pixmap( + bounds.x as i32, + bounds.y as i32, + temp_pixmap.as_ref(), + &tiny_skia::PixmapPaint::default(), + transform, + clip_mask, + ); + } + } + } + Primitive::Text { + content, + bounds, + color, + size, + line_height, + font, + horizontal_alignment, + vertical_alignment, + shaping, + } => { + let physical_bounds = + (primitive.bounds() + translation) * scale_factor; + + if !clip_bounds.intersects(&physical_bounds) { + return; + } + + let clip_mask = (!physical_bounds.is_within(&clip_bounds)) + .then_some(clip_mask as &_); + + self.text_pipeline.draw( + content, + *bounds + translation, + *color, + *size, + *line_height, + *font, + *horizontal_alignment, + *vertical_alignment, + *shaping, + scale_factor, + pixels, + clip_mask, + ); + } + #[cfg(feature = "image")] + Primitive::Image { handle, bounds } => { + let physical_bounds = (*bounds + translation) * scale_factor; + + if !clip_bounds.intersects(&physical_bounds) { + return; + } + + let clip_mask = (!physical_bounds.is_within(&clip_bounds)) + .then_some(clip_mask as &_); + + let transform = tiny_skia::Transform::from_translate( + translation.x, + translation.y, + ) + .post_scale(scale_factor, scale_factor); + + self.raster_pipeline + .draw(handle, *bounds, pixels, transform, clip_mask); + } + #[cfg(not(feature = "image"))] + Primitive::Image { .. } => { + log::warn!( + "Unsupported primitive in `iced_tiny_skia`: {:?}", + primitive + ); + } + #[cfg(feature = "svg")] + Primitive::Svg { + handle, + bounds, + color, + } => { + let physical_bounds = (*bounds + translation) * scale_factor; + + if !clip_bounds.intersects(&physical_bounds) { + return; + } + + let clip_mask = (!physical_bounds.is_within(&clip_bounds)) + .then_some(clip_mask as &_); + + self.vector_pipeline.draw( + handle, + *color, + (*bounds + translation) * scale_factor, + pixels, + clip_mask, + ); + } + #[cfg(not(feature = "svg"))] + Primitive::Svg { .. } => { + log::warn!( + "Unsupported primitive in `iced_tiny_skia`: {:?}", + primitive + ); + } + Primitive::Custom(primitive::Custom::Fill { + path, + paint, + rule, + transform, + }) => { + let bounds = path.bounds(); + + let physical_bounds = (Rectangle { + x: bounds.x(), + y: bounds.y(), + width: bounds.width(), + height: bounds.height(), + } + translation) + * scale_factor; + + if !clip_bounds.intersects(&physical_bounds) { + return; + } + + let clip_mask = (!physical_bounds.is_within(&clip_bounds)) + .then_some(clip_mask as &_); + + pixels.fill_path( + path, + paint, + *rule, + transform + .post_translate(translation.x, translation.y) + .post_scale(scale_factor, scale_factor), + clip_mask, + ); + } + Primitive::Custom(primitive::Custom::Stroke { + path, + paint, + stroke, + transform, + }) => { + let bounds = path.bounds(); + + let physical_bounds = (Rectangle { + x: bounds.x(), + y: bounds.y(), + width: bounds.width(), + height: bounds.height(), + } + translation) + * scale_factor; + + if !clip_bounds.intersects(&physical_bounds) { + return; + } + + let clip_mask = (!physical_bounds.is_within(&clip_bounds)) + .then_some(clip_mask as &_); + + pixels.stroke_path( + path, + paint, + stroke, + transform + .post_translate(translation.x, translation.y) + .post_scale(scale_factor, scale_factor), + clip_mask, + ); + } + Primitive::Group { primitives } => { + for primitive in primitives { + self.draw_primitive( + primitive, + pixels, + clip_mask, + clip_bounds, + scale_factor, + translation, + ); + } + } + Primitive::Translate { + translation: offset, + content, + } => { + self.draw_primitive( + content, + pixels, + clip_mask, + clip_bounds, + scale_factor, + translation + *offset, + ); + } + Primitive::Clip { bounds, content } => { + let bounds = (*bounds + translation) * scale_factor; + + if bounds == clip_bounds { + self.draw_primitive( + content, + pixels, + clip_mask, + bounds, + scale_factor, + translation, + ); + } else if let Some(bounds) = clip_bounds.intersection(&bounds) { + if bounds.x + bounds.width <= 0.0 + || bounds.y + bounds.height <= 0.0 + || bounds.x as u32 >= pixels.width() + || bounds.y as u32 >= pixels.height() + || bounds.width <= 1.0 + || bounds.height <= 1.0 + { + return; + } + + adjust_clip_mask(clip_mask, bounds); + + self.draw_primitive( + content, + pixels, + clip_mask, + bounds, + scale_factor, + translation, + ); + + adjust_clip_mask(clip_mask, clip_bounds); + } + } + Primitive::Cache { content } => { + self.draw_primitive( + content, + pixels, + clip_mask, + clip_bounds, + scale_factor, + translation, + ); + } + } + } +} + +fn into_color(color: Color) -> tiny_skia::Color { + tiny_skia::Color::from_rgba(color.b, color.g, color.r, color.a) + .expect("Convert color from iced to tiny_skia") +} + +fn rounded_rectangle( + bounds: Rectangle, + border_radius: [f32; 4], +) -> tiny_skia::Path { + let [top_left, top_right, bottom_right, bottom_left] = border_radius; + + if top_left == 0.0 + && top_right == 0.0 + && bottom_right == 0.0 + && bottom_left == 0.0 + { + return tiny_skia::PathBuilder::from_rect( + tiny_skia::Rect::from_xywh( + bounds.x, + bounds.y, + bounds.width, + bounds.height, + ) + .expect("Build quad rectangle"), + ); + } + + if top_left == top_right + && top_left == bottom_right + && top_left == bottom_left + && top_left == bounds.width / 2.0 + && top_left == bounds.height / 2.0 + { + return tiny_skia::PathBuilder::from_circle( + bounds.x + bounds.width / 2.0, + bounds.y + bounds.height / 2.0, + top_left, + ) + .expect("Build circle path"); + } + + let mut builder = tiny_skia::PathBuilder::new(); + + builder.move_to(bounds.x + top_left, bounds.y); + builder.line_to(bounds.x + bounds.width - top_right, bounds.y); + + if top_right > 0.0 { + arc_to( + &mut builder, + bounds.x + bounds.width - top_right, + bounds.y, + bounds.x + bounds.width, + bounds.y + top_right, + top_right, + ); + } + + maybe_line_to( + &mut builder, + bounds.x + bounds.width, + bounds.y + bounds.height - bottom_right, + ); + + if bottom_right > 0.0 { + arc_to( + &mut builder, + bounds.x + bounds.width, + bounds.y + bounds.height - bottom_right, + bounds.x + bounds.width - bottom_right, + bounds.y + bounds.height, + bottom_right, + ); + } + + maybe_line_to( + &mut builder, + bounds.x + bottom_left, + bounds.y + bounds.height, + ); + + if bottom_left > 0.0 { + arc_to( + &mut builder, + bounds.x + bottom_left, + bounds.y + bounds.height, + bounds.x, + bounds.y + bounds.height - bottom_left, + bottom_left, + ); + } + + maybe_line_to(&mut builder, bounds.x, bounds.y + top_left); + + if top_left > 0.0 { + arc_to( + &mut builder, + bounds.x, + bounds.y + top_left, + bounds.x + top_left, + bounds.y, + top_left, + ); + } + + builder.finish().expect("Build rounded rectangle path") +} + +fn maybe_line_to(path: &mut tiny_skia::PathBuilder, x: f32, y: f32) { + if path.last_point() != Some(tiny_skia::Point { x, y }) { + path.line_to(x, y); + } +} + +fn arc_to( + path: &mut tiny_skia::PathBuilder, + x_from: f32, + y_from: f32, + x_to: f32, + y_to: f32, + radius: f32, +) { + let svg_arc = kurbo::SvgArc { + from: kurbo::Point::new(f64::from(x_from), f64::from(y_from)), + to: kurbo::Point::new(f64::from(x_to), f64::from(y_to)), + radii: kurbo::Vec2::new(f64::from(radius), f64::from(radius)), + x_rotation: 0.0, + large_arc: false, + sweep: true, + }; + + match kurbo::Arc::from_svg_arc(&svg_arc) { + Some(arc) => { + arc.to_cubic_beziers(0.1, |p1, p2, p| { + path.cubic_to( + p1.x as f32, + p1.y as f32, + p2.x as f32, + p2.y as f32, + p.x as f32, + p.y as f32, + ); + }); + } + None => { + path.line_to(x_to, y_to); + } + } +} + +fn adjust_clip_mask(clip_mask: &mut tiny_skia::Mask, bounds: Rectangle) { + clip_mask.clear(); + + let path = { + let mut builder = tiny_skia::PathBuilder::new(); + builder.push_rect( + tiny_skia::Rect::from_xywh( + bounds.x, + bounds.y, + bounds.width, + bounds.height, + ) + .unwrap(), + ); + + builder.finish().unwrap() + }; + + clip_mask.fill_path( + &path, + tiny_skia::FillRule::EvenOdd, + false, + tiny_skia::Transform::default(), + ); +} + +impl iced_graphics::Backend for Backend { + type Primitive = primitive::Custom; +} + +impl backend::Text for Backend { + const ICON_FONT: Font = Font::with_name("Iced-Icons"); + const CHECKMARK_ICON: char = '\u{f00c}'; + const ARROW_DOWN_ICON: char = '\u{e800}'; + + fn default_font(&self) -> Font { + self.default_font + } + + fn default_size(&self) -> f32 { + self.default_text_size + } + + fn measure( + &self, + contents: &str, + size: f32, + line_height: text::LineHeight, + font: Font, + bounds: Size, + shaping: text::Shaping, + ) -> Size { + self.text_pipeline.measure( + contents, + size, + line_height, + font, + bounds, + shaping, + ) + } + + fn hit_test( + &self, + contents: &str, + size: f32, + line_height: text::LineHeight, + font: Font, + bounds: Size, + shaping: text::Shaping, + point: Point, + nearest_only: bool, + ) -> Option<text::Hit> { + self.text_pipeline.hit_test( + contents, + size, + line_height, + font, + bounds, + shaping, + point, + nearest_only, + ) + } + + fn load_font(&mut self, font: Cow<'static, [u8]>) { + self.text_pipeline.load_font(font); + } +} + +#[cfg(feature = "image")] +impl backend::Image for Backend { + fn dimensions(&self, handle: &crate::core::image::Handle) -> Size<u32> { + self.raster_pipeline.dimensions(handle) + } +} + +#[cfg(feature = "svg")] +impl backend::Svg for Backend { + fn viewport_dimensions( + &self, + handle: &crate::core::svg::Handle, + ) -> Size<u32> { + self.vector_pipeline.viewport_dimensions(handle) + } +} |