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style: Move SVGPathData and its parser into svg_path.rs.
SVGPathData will be used by clip-path and offset-path (and/or more on the properties which support <basic-shape>). Therefore, let's move SVGPathData out of motion.rs. Differential Revision: https://phabricator.services.mozilla.com/D3631
This commit is contained in:
Boris Chiou
Emilio Cobos Álvarez
parent
d4163eae96
commit
a92f9c105a
4 changed files with 522 additions and 500 deletions
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@ -68,6 +68,7 @@ pub use self::position::{PositionComponent, ZIndex};
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pub use self::svg::{SVGLength, SVGOpacity, SVGPaint, SVGPaintKind};
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pub use self::svg::{SVGPaintOrder, SVGStrokeDashArray, SVGWidth};
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pub use self::svg::MozContextProperties;
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pub use self::svg_path::SVGPathData;
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pub use self::table::XSpan;
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pub use self::text::{InitialLetter, LetterSpacing, LineHeight, MozTabSize, TextAlign};
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pub use self::text::{TextEmphasisPosition, TextEmphasisStyle};
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@ -109,6 +110,7 @@ pub mod rect;
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pub mod resolution;
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pub mod source_size_list;
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pub mod svg;
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pub mod svg_path;
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pub mod table;
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pub mod text;
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pub mod time;
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@ -6,12 +6,8 @@
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use cssparser::Parser;
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use parser::{Parse, ParserContext};
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use std::fmt::{self, Write};
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use std::iter::Peekable;
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use std::str::Chars;
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use style_traits::{CssWriter, ParseError, StyleParseErrorKind, ToCss};
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use style_traits::values::SequenceWriter;
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use values::CSSFloat;
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use style_traits::{ParseError, StyleParseErrorKind};
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use values::specified::SVGPathData;
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/// The offset-path value.
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///
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@ -63,496 +59,3 @@ impl Parse for OffsetPath {
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})
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}
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}
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/// SVG Path parser.
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struct PathParser<'a> {
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chars: Peekable<Chars<'a>>,
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path: Vec<PathCommand>,
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}
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macro_rules! parse_arguments {
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(
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$parser:ident,
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$abs:ident,
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$enum:ident,
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[ $para:ident => $func:ident $(, $other_para:ident => $other_func:ident)* ]
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) => {
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{
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loop {
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let $para = $func(&mut $parser.chars)?;
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$(
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skip_comma_wsp(&mut $parser.chars);
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let $other_para = $other_func(&mut $parser.chars)?;
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)*
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$parser.path.push(PathCommand::$enum { $para $(, $other_para)*, $abs });
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// End of string or the next character is a possible new command.
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if !skip_wsp(&mut $parser.chars) ||
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$parser.chars.peek().map_or(true, |c| c.is_ascii_alphabetic()) {
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break;
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}
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skip_comma_wsp(&mut $parser.chars);
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}
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Ok(())
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}
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}
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}
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impl<'a> PathParser<'a> {
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/// Parse a sub-path.
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fn parse_subpath(&mut self) -> Result<(), ()> {
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// Handle "moveto" Command first. If there is no "moveto", this is not a valid sub-path
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// (i.e. not a valid moveto-drawto-command-group).
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self.parse_moveto()?;
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// Handle other commands.
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loop {
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skip_wsp(&mut self.chars);
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if self.chars.peek().map_or(true, |m| *m == 'M' || *m == 'm') {
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break;
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}
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match self.chars.next() {
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Some(command) => {
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let abs = command.is_uppercase();
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macro_rules! parse_command {
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( $($($p:pat)|+ => $parse_func:ident,)* ) => {
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match command {
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$(
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$($p)|+ => {
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skip_wsp(&mut self.chars);
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self.$parse_func(abs)?;
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},
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)*
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_ => return Err(()),
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}
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}
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}
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parse_command!(
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'Z' | 'z' => parse_closepath,
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'L' | 'l' => parse_lineto,
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'H' | 'h' => parse_h_lineto,
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'V' | 'v' => parse_v_lineto,
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'C' | 'c' => parse_curveto,
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'S' | 's' => parse_smooth_curveto,
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'Q' | 'q' => parse_quadratic_bezier_curveto,
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'T' | 't' => parse_smooth_quadratic_bezier_curveto,
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'A' | 'a' => parse_elliprical_arc,
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);
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},
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_ => break, // no more commands.
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}
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}
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Ok(())
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}
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/// Parse "moveto" command.
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fn parse_moveto(&mut self) -> Result<(), ()> {
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let command = match self.chars.next() {
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Some(c) if c == 'M' || c == 'm' => c,
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_ => return Err(()),
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};
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skip_wsp(&mut self.chars);
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let point = parse_coord(&mut self.chars)?;
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let absolute = command == 'M';
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self.path.push(PathCommand::MoveTo { point, absolute } );
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// End of string or the next character is a possible new command.
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if !skip_wsp(&mut self.chars) ||
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self.chars.peek().map_or(true, |c| c.is_ascii_alphabetic()) {
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return Ok(());
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}
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skip_comma_wsp(&mut self.chars);
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// If a moveto is followed by multiple pairs of coordinates, the subsequent
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// pairs are treated as implicit lineto commands.
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self.parse_lineto(absolute)
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}
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/// Parse "closepath" command.
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fn parse_closepath(&mut self, _absolute: bool) -> Result<(), ()> {
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self.path.push(PathCommand::ClosePath);
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Ok(())
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}
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/// Parse "lineto" command.
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fn parse_lineto(&mut self, absolute: bool) -> Result<(), ()> {
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parse_arguments!(self, absolute, LineTo, [ point => parse_coord ])
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}
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/// Parse horizontal "lineto" command.
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fn parse_h_lineto(&mut self, absolute: bool) -> Result<(), ()> {
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parse_arguments!(self, absolute, HorizontalLineTo, [ x => parse_number ])
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}
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/// Parse vertical "lineto" command.
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fn parse_v_lineto(&mut self, absolute: bool) -> Result<(), ()> {
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parse_arguments!(self, absolute, VerticalLineTo, [ y => parse_number ])
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}
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/// Parse cubic Bézier curve command.
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fn parse_curveto(&mut self, absolute: bool) -> Result<(), ()> {
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parse_arguments!(self, absolute, CurveTo, [
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control1 => parse_coord, control2 => parse_coord, point => parse_coord
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])
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}
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/// Parse smooth "curveto" command.
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fn parse_smooth_curveto(&mut self, absolute: bool) -> Result<(), ()> {
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parse_arguments!(self, absolute, SmoothCurveTo, [
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control2 => parse_coord, point => parse_coord
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])
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}
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/// Parse quadratic Bézier curve command.
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fn parse_quadratic_bezier_curveto(&mut self, absolute: bool) -> Result<(), ()> {
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parse_arguments!(self, absolute, QuadBezierCurveTo, [
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control1 => parse_coord, point => parse_coord
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])
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}
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/// Parse smooth quadratic Bézier curveto command.
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fn parse_smooth_quadratic_bezier_curveto(&mut self, absolute: bool) -> Result<(), ()> {
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parse_arguments!(self, absolute, SmoothQuadBezierCurveTo, [ point => parse_coord ])
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}
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/// Parse elliptical arc curve command.
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fn parse_elliprical_arc(&mut self, absolute: bool) -> Result<(), ()> {
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// Parse a flag whose value is '0' or '1'; otherwise, return Err(()).
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let parse_flag = |iter: &mut Peekable<Chars>| -> Result<bool, ()> {
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let value = match iter.peek() {
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Some(c) if *c == '0' || *c == '1' => *c == '1',
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_ => return Err(()),
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};
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iter.next();
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Ok(value)
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};
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parse_arguments!(self, absolute, EllipticalArc, [
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rx => parse_number,
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ry => parse_number,
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angle => parse_number,
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large_arc_flag => parse_flag,
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sweep_flag => parse_flag,
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point => parse_coord
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])
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}
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}
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/// The SVG path data.
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///
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/// https://www.w3.org/TR/SVG11/paths.html#PathData
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#[derive(Clone, Debug, MallocSizeOf, PartialEq, SpecifiedValueInfo, ToComputedValue)]
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pub struct SVGPathData(Box<[PathCommand]>);
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impl SVGPathData {
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/// Return SVGPathData by a slice of PathCommand.
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#[inline]
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pub fn new(cmd: Box<[PathCommand]>) -> Self {
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debug_assert!(!cmd.is_empty());
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SVGPathData(cmd)
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}
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/// Get the array of PathCommand.
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#[inline]
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pub fn commands(&self) -> &[PathCommand] {
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debug_assert!(!self.0.is_empty());
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&self.0
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}
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}
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impl ToCss for SVGPathData {
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#[inline]
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fn to_css<W>(&self, dest: &mut CssWriter<W>) -> fmt::Result
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where
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W: fmt::Write
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{
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dest.write_char('"')?;
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{
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let mut writer = SequenceWriter::new(dest, " ");
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for command in self.0.iter() {
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writer.item(command)?;
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}
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}
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dest.write_char('"')
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}
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}
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impl Parse for SVGPathData {
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// We cannot use cssparser::Parser to parse a SVG path string because the spec wants to make
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// the SVG path string as compact as possible. (i.e. The whitespaces may be dropped.)
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// e.g. "M100 200L100 200" is a valid SVG path string. If we use tokenizer, the first ident
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// is "M100", instead of "M", and this is not correct. Therefore, we use a Peekable
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// str::Char iterator to check each character.
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fn parse<'i, 't>(
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_context: &ParserContext,
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input: &mut Parser<'i, 't>
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) -> Result<Self, ParseError<'i>> {
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let location = input.current_source_location();
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let path_string = input.expect_string()?.as_ref();
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if path_string.is_empty() {
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// Treat an empty string as invalid, so we will not set it.
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return Err(location.new_custom_error(StyleParseErrorKind::UnspecifiedError));
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}
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// Parse the svg path string as multiple sub-paths.
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let mut path_parser = PathParser {
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chars: path_string.chars().peekable(),
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path: Vec::new(),
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};
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while skip_wsp(&mut path_parser.chars) {
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if path_parser.parse_subpath().is_err() {
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return Err(location.new_custom_error(StyleParseErrorKind::UnspecifiedError));
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}
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}
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Ok(SVGPathData::new(path_parser.path.into_boxed_slice()))
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}
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}
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/// The SVG path command.
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/// The fields of these commands are self-explanatory, so we skip the documents.
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/// Note: the index of the control points, e.g. control1, control2, are mapping to the control
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/// points of the Bézier curve in the spec.
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///
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/// https://www.w3.org/TR/SVG11/paths.html#PathData
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#[derive(Clone, Copy, Debug, MallocSizeOf, PartialEq, SpecifiedValueInfo)]
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#[allow(missing_docs)]
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#[repr(C, u8)]
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pub enum PathCommand {
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/// The unknown type.
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/// https://www.w3.org/TR/SVG/paths.html#__svg__SVGPathSeg__PATHSEG_UNKNOWN
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Unknown,
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/// The "moveto" command.
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MoveTo { point: CoordPair, absolute: bool },
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/// The "lineto" command.
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LineTo { point: CoordPair, absolute: bool },
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/// The horizontal "lineto" command.
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HorizontalLineTo { x: CSSFloat, absolute: bool },
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/// The vertical "lineto" command.
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VerticalLineTo { y: CSSFloat, absolute: bool },
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/// The cubic Bézier curve command.
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CurveTo { control1: CoordPair, control2: CoordPair, point: CoordPair, absolute: bool },
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/// The smooth curve command.
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SmoothCurveTo { control2: CoordPair, point: CoordPair, absolute: bool },
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/// The quadratic Bézier curve command.
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QuadBezierCurveTo { control1: CoordPair, point: CoordPair, absolute: bool },
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/// The smooth quadratic Bézier curve command.
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SmoothQuadBezierCurveTo { point: CoordPair, absolute: bool },
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/// The elliptical arc curve command.
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EllipticalArc {
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rx: CSSFloat,
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ry: CSSFloat,
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angle: CSSFloat,
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large_arc_flag: bool,
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sweep_flag: bool,
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point: CoordPair,
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absolute: bool
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},
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/// The "closepath" command.
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ClosePath,
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}
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impl ToCss for PathCommand {
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fn to_css<W>(&self, dest: &mut CssWriter<W>) -> fmt::Result
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where
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W: fmt::Write
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{
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use self::PathCommand::*;
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match *self {
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Unknown => dest.write_str("X"),
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ClosePath => dest.write_str("Z"),
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MoveTo { point, absolute } => {
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dest.write_char(if absolute { 'M' } else { 'm' })?;
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dest.write_char(' ')?;
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point.to_css(dest)
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}
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LineTo { point, absolute } => {
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dest.write_char(if absolute { 'L' } else { 'l' })?;
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dest.write_char(' ')?;
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point.to_css(dest)
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}
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CurveTo { control1, control2, point, absolute } => {
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dest.write_char(if absolute { 'C' } else { 'c' })?;
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dest.write_char(' ')?;
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control1.to_css(dest)?;
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dest.write_char(' ')?;
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control2.to_css(dest)?;
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dest.write_char(' ')?;
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point.to_css(dest)
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},
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QuadBezierCurveTo { control1, point, absolute } => {
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dest.write_char(if absolute { 'Q' } else { 'q' })?;
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dest.write_char(' ')?;
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control1.to_css(dest)?;
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dest.write_char(' ')?;
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point.to_css(dest)
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},
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EllipticalArc { rx, ry, angle, large_arc_flag, sweep_flag, point, absolute } => {
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dest.write_char(if absolute { 'A' } else { 'a' })?;
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dest.write_char(' ')?;
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rx.to_css(dest)?;
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dest.write_char(' ')?;
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ry.to_css(dest)?;
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dest.write_char(' ')?;
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angle.to_css(dest)?;
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dest.write_char(' ')?;
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(large_arc_flag as i32).to_css(dest)?;
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dest.write_char(' ')?;
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(sweep_flag as i32).to_css(dest)?;
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dest.write_char(' ')?;
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point.to_css(dest)
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},
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HorizontalLineTo { x, absolute } => {
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dest.write_char(if absolute { 'H' } else { 'h' })?;
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dest.write_char(' ')?;
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x.to_css(dest)
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},
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VerticalLineTo { y, absolute } => {
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dest.write_char(if absolute { 'V' } else { 'v' })?;
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dest.write_char(' ')?;
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y.to_css(dest)
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},
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SmoothCurveTo { control2, point, absolute } => {
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dest.write_char(if absolute { 'S' } else { 's' })?;
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dest.write_char(' ')?;
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control2.to_css(dest)?;
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dest.write_char(' ')?;
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point.to_css(dest)
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},
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SmoothQuadBezierCurveTo { point, absolute } => {
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dest.write_char(if absolute { 'T' } else { 't' })?;
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dest.write_char(' ')?;
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point.to_css(dest)
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},
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}
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}
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}
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/// The path coord type.
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#[derive(Clone, Copy, Debug, MallocSizeOf, PartialEq, SpecifiedValueInfo, ToCss)]
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#[repr(C)]
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pub struct CoordPair(CSSFloat, CSSFloat);
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impl CoordPair {
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/// Create a CoordPair.
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#[inline]
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pub fn new(x: CSSFloat, y: CSSFloat) -> Self {
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CoordPair(x, y)
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}
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}
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/// Parse a pair of numbers into CoordPair.
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fn parse_coord(iter: &mut Peekable<Chars>) -> Result<CoordPair, ()> {
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let x = parse_number(iter)?;
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skip_comma_wsp(iter);
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let y = parse_number(iter)?;
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Ok(CoordPair::new(x, y))
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}
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/// This is a special version which parses the number for SVG Path. e.g. "M 0.6.5" should be parsed
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/// as MoveTo with a coordinate of ("0.6", ".5"), instead of treating 0.6.5 as a non-valid floating
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/// point number. In other words, the logic here is similar with that of
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/// tokenizer::consume_numeric, which also consumes the number as many as possible, but here the
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/// input is a Peekable and we only accept an integer of a floating point number.
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///
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/// The "number" syntax in https://www.w3.org/TR/SVG/paths.html#PathDataBNF
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fn parse_number(iter: &mut Peekable<Chars>) -> Result<CSSFloat, ()> {
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// 1. Check optional sign.
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let sign = if iter.peek().map_or(false, |&sign: &char| sign == '+' || sign == '-') {
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if iter.next().unwrap() == '-' { -1. } else { 1. }
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} else {
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1.
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};
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// 2. Check integer part.
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let mut integral_part: f64 = 0.;
|
||||
let got_dot = if !iter.peek().map_or(false, |&n: &char| n == '.') {
|
||||
// If the first digit in integer part is neither a dot nor a digit, this is not a number.
|
||||
if iter.peek().map_or(true, |n: &char| !n.is_ascii_digit()) {
|
||||
return Err(());
|
||||
}
|
||||
|
||||
while iter.peek().map_or(false, |n: &char| n.is_ascii_digit()) {
|
||||
integral_part =
|
||||
integral_part * 10. + iter.next().unwrap().to_digit(10).unwrap() as f64;
|
||||
}
|
||||
|
||||
iter.peek().map_or(false, |&n: &char| n == '.')
|
||||
} else {
|
||||
true
|
||||
};
|
||||
|
||||
// 3. Check fractional part.
|
||||
let mut fractional_part: f64 = 0.;
|
||||
if got_dot {
|
||||
// Consume '.'.
|
||||
iter.next();
|
||||
// If the first digit in fractional part is not a digit, this is not a number.
|
||||
if iter.peek().map_or(true, |n: &char| !n.is_ascii_digit()) {
|
||||
return Err(());
|
||||
}
|
||||
|
||||
let mut factor = 0.1;
|
||||
while iter.peek().map_or(false, |n: &char| n.is_ascii_digit()) {
|
||||
fractional_part += iter.next().unwrap().to_digit(10).unwrap() as f64 * factor;
|
||||
factor *= 0.1;
|
||||
}
|
||||
}
|
||||
|
||||
let mut value = sign * (integral_part + fractional_part);
|
||||
|
||||
// 4. Check exp part. The segment name of SVG Path doesn't include 'E' or 'e', so it's ok to
|
||||
// treat the numbers after 'E' or 'e' are in the exponential part.
|
||||
if iter.peek().map_or(false, |&exp: &char| exp == 'E' || exp == 'e') {
|
||||
// Consume 'E' or 'e'.
|
||||
iter.next();
|
||||
let exp_sign = if iter.peek().map_or(false, |&sign: &char| sign == '+' || sign == '-') {
|
||||
if iter.next().unwrap() == '-' { -1. } else { 1. }
|
||||
} else {
|
||||
1.
|
||||
};
|
||||
|
||||
let mut exp: f64 = 0.;
|
||||
while iter.peek().map_or(false, |n: &char| n.is_ascii_digit()) {
|
||||
exp = exp * 10. + iter.next().unwrap().to_digit(10).unwrap() as f64;
|
||||
}
|
||||
|
||||
value *= f64::powf(10., exp * exp_sign);
|
||||
}
|
||||
|
||||
if value.is_finite() {
|
||||
Ok(value.min(::std::f32::MAX as f64).max(::std::f32::MIN as f64) as CSSFloat)
|
||||
} else {
|
||||
Err(())
|
||||
}
|
||||
}
|
||||
|
||||
/// Skip all svg whitespaces, and return true if |iter| hasn't finished.
|
||||
#[inline]
|
||||
fn skip_wsp(iter: &mut Peekable<Chars>) -> bool {
|
||||
// Note: SVG 1.1 defines the whitespaces as \u{9}, \u{20}, \u{A}, \u{D}.
|
||||
// However, SVG 2 has one extra whitespace: \u{C}.
|
||||
// Therefore, we follow the newest spec for the definition of whitespace,
|
||||
// i.e. \u{9}, \u{20}, \u{A}, \u{C}, \u{D}, by is_ascii_whitespace().
|
||||
while iter.peek().map_or(false, |c: &char| c.is_ascii_whitespace()) {
|
||||
iter.next();
|
||||
}
|
||||
iter.peek().is_some()
|
||||
}
|
||||
|
||||
/// Skip all svg whitespaces and one comma, and return true if |iter| hasn't finished.
|
||||
#[inline]
|
||||
fn skip_comma_wsp(iter: &mut Peekable<Chars>) -> bool {
|
||||
if !skip_wsp(iter) {
|
||||
return false;
|
||||
}
|
||||
|
||||
if *iter.peek().unwrap() != ',' {
|
||||
return true;
|
||||
}
|
||||
iter.next();
|
||||
|
||||
skip_wsp(iter)
|
||||
}
|
||||
|
|
|
|||
517
components/style/values/specified/svg_path.rs
Normal file
517
components/style/values/specified/svg_path.rs
Normal file
|
|
@ -0,0 +1,517 @@
|
|||
/* This Source Code Form is subject to the terms of the Mozilla Public
|
||||
* License, v. 2.0. If a copy of the MPL was not distributed with this
|
||||
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
|
||||
|
||||
//! Specified types for SVG Path.
|
||||
|
||||
use cssparser::Parser;
|
||||
use parser::{Parse, ParserContext};
|
||||
use std::fmt::{self, Write};
|
||||
use std::iter::Peekable;
|
||||
use std::str::Chars;
|
||||
use style_traits::{CssWriter, ParseError, StyleParseErrorKind, ToCss};
|
||||
use style_traits::values::SequenceWriter;
|
||||
use values::CSSFloat;
|
||||
|
||||
|
||||
/// The SVG path data.
|
||||
///
|
||||
/// https://www.w3.org/TR/SVG11/paths.html#PathData
|
||||
#[derive(Clone, Debug, MallocSizeOf, PartialEq, SpecifiedValueInfo, ToComputedValue)]
|
||||
pub struct SVGPathData(Box<[PathCommand]>);
|
||||
|
||||
impl SVGPathData {
|
||||
/// Return SVGPathData by a slice of PathCommand.
|
||||
#[inline]
|
||||
pub fn new(cmd: Box<[PathCommand]>) -> Self {
|
||||
debug_assert!(!cmd.is_empty());
|
||||
SVGPathData(cmd)
|
||||
}
|
||||
|
||||
/// Get the array of PathCommand.
|
||||
#[inline]
|
||||
pub fn commands(&self) -> &[PathCommand] {
|
||||
debug_assert!(!self.0.is_empty());
|
||||
&self.0
|
||||
}
|
||||
}
|
||||
|
||||
impl ToCss for SVGPathData {
|
||||
#[inline]
|
||||
fn to_css<W>(&self, dest: &mut CssWriter<W>) -> fmt::Result
|
||||
where
|
||||
W: fmt::Write
|
||||
{
|
||||
dest.write_char('"')?;
|
||||
{
|
||||
let mut writer = SequenceWriter::new(dest, " ");
|
||||
for command in self.0.iter() {
|
||||
writer.item(command)?;
|
||||
}
|
||||
}
|
||||
dest.write_char('"')
|
||||
}
|
||||
}
|
||||
|
||||
impl Parse for SVGPathData {
|
||||
// We cannot use cssparser::Parser to parse a SVG path string because the spec wants to make
|
||||
// the SVG path string as compact as possible. (i.e. The whitespaces may be dropped.)
|
||||
// e.g. "M100 200L100 200" is a valid SVG path string. If we use tokenizer, the first ident
|
||||
// is "M100", instead of "M", and this is not correct. Therefore, we use a Peekable
|
||||
// str::Char iterator to check each character.
|
||||
fn parse<'i, 't>(
|
||||
_context: &ParserContext,
|
||||
input: &mut Parser<'i, 't>
|
||||
) -> Result<Self, ParseError<'i>> {
|
||||
let location = input.current_source_location();
|
||||
let path_string = input.expect_string()?.as_ref();
|
||||
if path_string.is_empty() {
|
||||
// Treat an empty string as invalid, so we will not set it.
|
||||
return Err(location.new_custom_error(StyleParseErrorKind::UnspecifiedError));
|
||||
}
|
||||
|
||||
// Parse the svg path string as multiple sub-paths.
|
||||
let mut path_parser = PathParser::new(path_string);
|
||||
while skip_wsp(&mut path_parser.chars) {
|
||||
if path_parser.parse_subpath().is_err() {
|
||||
return Err(location.new_custom_error(StyleParseErrorKind::UnspecifiedError));
|
||||
}
|
||||
}
|
||||
|
||||
Ok(SVGPathData::new(path_parser.path.into_boxed_slice()))
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
/// The SVG path command.
|
||||
/// The fields of these commands are self-explanatory, so we skip the documents.
|
||||
/// Note: the index of the control points, e.g. control1, control2, are mapping to the control
|
||||
/// points of the Bézier curve in the spec.
|
||||
///
|
||||
/// https://www.w3.org/TR/SVG11/paths.html#PathData
|
||||
#[derive(Clone, Copy, Debug, MallocSizeOf, PartialEq, SpecifiedValueInfo)]
|
||||
#[allow(missing_docs)]
|
||||
#[repr(C, u8)]
|
||||
pub enum PathCommand {
|
||||
/// The unknown type.
|
||||
/// https://www.w3.org/TR/SVG/paths.html#__svg__SVGPathSeg__PATHSEG_UNKNOWN
|
||||
Unknown,
|
||||
/// The "moveto" command.
|
||||
MoveTo { point: CoordPair, absolute: bool },
|
||||
/// The "lineto" command.
|
||||
LineTo { point: CoordPair, absolute: bool },
|
||||
/// The horizontal "lineto" command.
|
||||
HorizontalLineTo { x: CSSFloat, absolute: bool },
|
||||
/// The vertical "lineto" command.
|
||||
VerticalLineTo { y: CSSFloat, absolute: bool },
|
||||
/// The cubic Bézier curve command.
|
||||
CurveTo { control1: CoordPair, control2: CoordPair, point: CoordPair, absolute: bool },
|
||||
/// The smooth curve command.
|
||||
SmoothCurveTo { control2: CoordPair, point: CoordPair, absolute: bool },
|
||||
/// The quadratic Bézier curve command.
|
||||
QuadBezierCurveTo { control1: CoordPair, point: CoordPair, absolute: bool },
|
||||
/// The smooth quadratic Bézier curve command.
|
||||
SmoothQuadBezierCurveTo { point: CoordPair, absolute: bool },
|
||||
/// The elliptical arc curve command.
|
||||
EllipticalArc {
|
||||
rx: CSSFloat,
|
||||
ry: CSSFloat,
|
||||
angle: CSSFloat,
|
||||
large_arc_flag: bool,
|
||||
sweep_flag: bool,
|
||||
point: CoordPair,
|
||||
absolute: bool
|
||||
},
|
||||
/// The "closepath" command.
|
||||
ClosePath,
|
||||
}
|
||||
|
||||
impl ToCss for PathCommand {
|
||||
fn to_css<W>(&self, dest: &mut CssWriter<W>) -> fmt::Result
|
||||
where
|
||||
W: fmt::Write
|
||||
{
|
||||
use self::PathCommand::*;
|
||||
match *self {
|
||||
Unknown => dest.write_str("X"),
|
||||
ClosePath => dest.write_str("Z"),
|
||||
MoveTo { point, absolute } => {
|
||||
dest.write_char(if absolute { 'M' } else { 'm' })?;
|
||||
dest.write_char(' ')?;
|
||||
point.to_css(dest)
|
||||
}
|
||||
LineTo { point, absolute } => {
|
||||
dest.write_char(if absolute { 'L' } else { 'l' })?;
|
||||
dest.write_char(' ')?;
|
||||
point.to_css(dest)
|
||||
}
|
||||
CurveTo { control1, control2, point, absolute } => {
|
||||
dest.write_char(if absolute { 'C' } else { 'c' })?;
|
||||
dest.write_char(' ')?;
|
||||
control1.to_css(dest)?;
|
||||
dest.write_char(' ')?;
|
||||
control2.to_css(dest)?;
|
||||
dest.write_char(' ')?;
|
||||
point.to_css(dest)
|
||||
},
|
||||
QuadBezierCurveTo { control1, point, absolute } => {
|
||||
dest.write_char(if absolute { 'Q' } else { 'q' })?;
|
||||
dest.write_char(' ')?;
|
||||
control1.to_css(dest)?;
|
||||
dest.write_char(' ')?;
|
||||
point.to_css(dest)
|
||||
},
|
||||
EllipticalArc { rx, ry, angle, large_arc_flag, sweep_flag, point, absolute } => {
|
||||
dest.write_char(if absolute { 'A' } else { 'a' })?;
|
||||
dest.write_char(' ')?;
|
||||
rx.to_css(dest)?;
|
||||
dest.write_char(' ')?;
|
||||
ry.to_css(dest)?;
|
||||
dest.write_char(' ')?;
|
||||
angle.to_css(dest)?;
|
||||
dest.write_char(' ')?;
|
||||
(large_arc_flag as i32).to_css(dest)?;
|
||||
dest.write_char(' ')?;
|
||||
(sweep_flag as i32).to_css(dest)?;
|
||||
dest.write_char(' ')?;
|
||||
point.to_css(dest)
|
||||
},
|
||||
HorizontalLineTo { x, absolute } => {
|
||||
dest.write_char(if absolute { 'H' } else { 'h' })?;
|
||||
dest.write_char(' ')?;
|
||||
x.to_css(dest)
|
||||
},
|
||||
VerticalLineTo { y, absolute } => {
|
||||
dest.write_char(if absolute { 'V' } else { 'v' })?;
|
||||
dest.write_char(' ')?;
|
||||
y.to_css(dest)
|
||||
},
|
||||
SmoothCurveTo { control2, point, absolute } => {
|
||||
dest.write_char(if absolute { 'S' } else { 's' })?;
|
||||
dest.write_char(' ')?;
|
||||
control2.to_css(dest)?;
|
||||
dest.write_char(' ')?;
|
||||
point.to_css(dest)
|
||||
},
|
||||
SmoothQuadBezierCurveTo { point, absolute } => {
|
||||
dest.write_char(if absolute { 'T' } else { 't' })?;
|
||||
dest.write_char(' ')?;
|
||||
point.to_css(dest)
|
||||
},
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
/// The path coord type.
|
||||
#[derive(Clone, Copy, Debug, MallocSizeOf, PartialEq, SpecifiedValueInfo, ToCss)]
|
||||
#[repr(C)]
|
||||
pub struct CoordPair(CSSFloat, CSSFloat);
|
||||
|
||||
impl CoordPair {
|
||||
/// Create a CoordPair.
|
||||
#[inline]
|
||||
pub fn new(x: CSSFloat, y: CSSFloat) -> Self {
|
||||
CoordPair(x, y)
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
/// SVG Path parser.
|
||||
struct PathParser<'a> {
|
||||
chars: Peekable<Chars<'a>>,
|
||||
path: Vec<PathCommand>,
|
||||
}
|
||||
|
||||
macro_rules! parse_arguments {
|
||||
(
|
||||
$parser:ident,
|
||||
$abs:ident,
|
||||
$enum:ident,
|
||||
[ $para:ident => $func:ident $(, $other_para:ident => $other_func:ident)* ]
|
||||
) => {
|
||||
{
|
||||
loop {
|
||||
let $para = $func(&mut $parser.chars)?;
|
||||
$(
|
||||
skip_comma_wsp(&mut $parser.chars);
|
||||
let $other_para = $other_func(&mut $parser.chars)?;
|
||||
)*
|
||||
$parser.path.push(PathCommand::$enum { $para $(, $other_para)*, $abs });
|
||||
|
||||
// End of string or the next character is a possible new command.
|
||||
if !skip_wsp(&mut $parser.chars) ||
|
||||
$parser.chars.peek().map_or(true, |c| c.is_ascii_alphabetic()) {
|
||||
break;
|
||||
}
|
||||
skip_comma_wsp(&mut $parser.chars);
|
||||
}
|
||||
Ok(())
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
impl<'a> PathParser<'a> {
|
||||
/// Return a PathParser.
|
||||
#[inline]
|
||||
fn new(string: &'a str) -> Self {
|
||||
PathParser {
|
||||
chars: string.chars().peekable(),
|
||||
path: Vec::new(),
|
||||
}
|
||||
}
|
||||
|
||||
/// Parse a sub-path.
|
||||
fn parse_subpath(&mut self) -> Result<(), ()> {
|
||||
// Handle "moveto" Command first. If there is no "moveto", this is not a valid sub-path
|
||||
// (i.e. not a valid moveto-drawto-command-group).
|
||||
self.parse_moveto()?;
|
||||
|
||||
// Handle other commands.
|
||||
loop {
|
||||
skip_wsp(&mut self.chars);
|
||||
if self.chars.peek().map_or(true, |m| *m == 'M' || *m == 'm') {
|
||||
break;
|
||||
}
|
||||
|
||||
match self.chars.next() {
|
||||
Some(command) => {
|
||||
let abs = command.is_uppercase();
|
||||
macro_rules! parse_command {
|
||||
( $($($p:pat)|+ => $parse_func:ident,)* ) => {
|
||||
match command {
|
||||
$(
|
||||
$($p)|+ => {
|
||||
skip_wsp(&mut self.chars);
|
||||
self.$parse_func(abs)?;
|
||||
},
|
||||
)*
|
||||
_ => return Err(()),
|
||||
}
|
||||
}
|
||||
}
|
||||
parse_command!(
|
||||
'Z' | 'z' => parse_closepath,
|
||||
'L' | 'l' => parse_lineto,
|
||||
'H' | 'h' => parse_h_lineto,
|
||||
'V' | 'v' => parse_v_lineto,
|
||||
'C' | 'c' => parse_curveto,
|
||||
'S' | 's' => parse_smooth_curveto,
|
||||
'Q' | 'q' => parse_quadratic_bezier_curveto,
|
||||
'T' | 't' => parse_smooth_quadratic_bezier_curveto,
|
||||
'A' | 'a' => parse_elliprical_arc,
|
||||
);
|
||||
},
|
||||
_ => break, // no more commands.
|
||||
}
|
||||
}
|
||||
Ok(())
|
||||
}
|
||||
|
||||
/// Parse "moveto" command.
|
||||
fn parse_moveto(&mut self) -> Result<(), ()> {
|
||||
let command = match self.chars.next() {
|
||||
Some(c) if c == 'M' || c == 'm' => c,
|
||||
_ => return Err(()),
|
||||
};
|
||||
|
||||
skip_wsp(&mut self.chars);
|
||||
let point = parse_coord(&mut self.chars)?;
|
||||
let absolute = command == 'M';
|
||||
self.path.push(PathCommand::MoveTo { point, absolute } );
|
||||
|
||||
// End of string or the next character is a possible new command.
|
||||
if !skip_wsp(&mut self.chars) ||
|
||||
self.chars.peek().map_or(true, |c| c.is_ascii_alphabetic()) {
|
||||
return Ok(());
|
||||
}
|
||||
skip_comma_wsp(&mut self.chars);
|
||||
|
||||
// If a moveto is followed by multiple pairs of coordinates, the subsequent
|
||||
// pairs are treated as implicit lineto commands.
|
||||
self.parse_lineto(absolute)
|
||||
}
|
||||
|
||||
/// Parse "closepath" command.
|
||||
fn parse_closepath(&mut self, _absolute: bool) -> Result<(), ()> {
|
||||
self.path.push(PathCommand::ClosePath);
|
||||
Ok(())
|
||||
}
|
||||
|
||||
/// Parse "lineto" command.
|
||||
fn parse_lineto(&mut self, absolute: bool) -> Result<(), ()> {
|
||||
parse_arguments!(self, absolute, LineTo, [ point => parse_coord ])
|
||||
}
|
||||
|
||||
/// Parse horizontal "lineto" command.
|
||||
fn parse_h_lineto(&mut self, absolute: bool) -> Result<(), ()> {
|
||||
parse_arguments!(self, absolute, HorizontalLineTo, [ x => parse_number ])
|
||||
}
|
||||
|
||||
/// Parse vertical "lineto" command.
|
||||
fn parse_v_lineto(&mut self, absolute: bool) -> Result<(), ()> {
|
||||
parse_arguments!(self, absolute, VerticalLineTo, [ y => parse_number ])
|
||||
}
|
||||
|
||||
/// Parse cubic Bézier curve command.
|
||||
fn parse_curveto(&mut self, absolute: bool) -> Result<(), ()> {
|
||||
parse_arguments!(self, absolute, CurveTo, [
|
||||
control1 => parse_coord, control2 => parse_coord, point => parse_coord
|
||||
])
|
||||
}
|
||||
|
||||
/// Parse smooth "curveto" command.
|
||||
fn parse_smooth_curveto(&mut self, absolute: bool) -> Result<(), ()> {
|
||||
parse_arguments!(self, absolute, SmoothCurveTo, [
|
||||
control2 => parse_coord, point => parse_coord
|
||||
])
|
||||
}
|
||||
|
||||
/// Parse quadratic Bézier curve command.
|
||||
fn parse_quadratic_bezier_curveto(&mut self, absolute: bool) -> Result<(), ()> {
|
||||
parse_arguments!(self, absolute, QuadBezierCurveTo, [
|
||||
control1 => parse_coord, point => parse_coord
|
||||
])
|
||||
}
|
||||
|
||||
/// Parse smooth quadratic Bézier curveto command.
|
||||
fn parse_smooth_quadratic_bezier_curveto(&mut self, absolute: bool) -> Result<(), ()> {
|
||||
parse_arguments!(self, absolute, SmoothQuadBezierCurveTo, [ point => parse_coord ])
|
||||
}
|
||||
|
||||
/// Parse elliptical arc curve command.
|
||||
fn parse_elliprical_arc(&mut self, absolute: bool) -> Result<(), ()> {
|
||||
// Parse a flag whose value is '0' or '1'; otherwise, return Err(()).
|
||||
let parse_flag = |iter: &mut Peekable<Chars>| -> Result<bool, ()> {
|
||||
let value = match iter.peek() {
|
||||
Some(c) if *c == '0' || *c == '1' => *c == '1',
|
||||
_ => return Err(()),
|
||||
};
|
||||
iter.next();
|
||||
Ok(value)
|
||||
};
|
||||
parse_arguments!(self, absolute, EllipticalArc, [
|
||||
rx => parse_number,
|
||||
ry => parse_number,
|
||||
angle => parse_number,
|
||||
large_arc_flag => parse_flag,
|
||||
sweep_flag => parse_flag,
|
||||
point => parse_coord
|
||||
])
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
/// Parse a pair of numbers into CoordPair.
|
||||
fn parse_coord(iter: &mut Peekable<Chars>) -> Result<CoordPair, ()> {
|
||||
let x = parse_number(iter)?;
|
||||
skip_comma_wsp(iter);
|
||||
let y = parse_number(iter)?;
|
||||
Ok(CoordPair::new(x, y))
|
||||
}
|
||||
|
||||
/// This is a special version which parses the number for SVG Path. e.g. "M 0.6.5" should be parsed
|
||||
/// as MoveTo with a coordinate of ("0.6", ".5"), instead of treating 0.6.5 as a non-valid floating
|
||||
/// point number. In other words, the logic here is similar with that of
|
||||
/// tokenizer::consume_numeric, which also consumes the number as many as possible, but here the
|
||||
/// input is a Peekable and we only accept an integer of a floating point number.
|
||||
///
|
||||
/// The "number" syntax in https://www.w3.org/TR/SVG/paths.html#PathDataBNF
|
||||
fn parse_number(iter: &mut Peekable<Chars>) -> Result<CSSFloat, ()> {
|
||||
// 1. Check optional sign.
|
||||
let sign = if iter.peek().map_or(false, |&sign: &char| sign == '+' || sign == '-') {
|
||||
if iter.next().unwrap() == '-' { -1. } else { 1. }
|
||||
} else {
|
||||
1.
|
||||
};
|
||||
|
||||
// 2. Check integer part.
|
||||
let mut integral_part: f64 = 0.;
|
||||
let got_dot = if !iter.peek().map_or(false, |&n: &char| n == '.') {
|
||||
// If the first digit in integer part is neither a dot nor a digit, this is not a number.
|
||||
if iter.peek().map_or(true, |n: &char| !n.is_ascii_digit()) {
|
||||
return Err(());
|
||||
}
|
||||
|
||||
while iter.peek().map_or(false, |n: &char| n.is_ascii_digit()) {
|
||||
integral_part =
|
||||
integral_part * 10. + iter.next().unwrap().to_digit(10).unwrap() as f64;
|
||||
}
|
||||
|
||||
iter.peek().map_or(false, |&n: &char| n == '.')
|
||||
} else {
|
||||
true
|
||||
};
|
||||
|
||||
// 3. Check fractional part.
|
||||
let mut fractional_part: f64 = 0.;
|
||||
if got_dot {
|
||||
// Consume '.'.
|
||||
iter.next();
|
||||
// If the first digit in fractional part is not a digit, this is not a number.
|
||||
if iter.peek().map_or(true, |n: &char| !n.is_ascii_digit()) {
|
||||
return Err(());
|
||||
}
|
||||
|
||||
let mut factor = 0.1;
|
||||
while iter.peek().map_or(false, |n: &char| n.is_ascii_digit()) {
|
||||
fractional_part += iter.next().unwrap().to_digit(10).unwrap() as f64 * factor;
|
||||
factor *= 0.1;
|
||||
}
|
||||
}
|
||||
|
||||
let mut value = sign * (integral_part + fractional_part);
|
||||
|
||||
// 4. Check exp part. The segment name of SVG Path doesn't include 'E' or 'e', so it's ok to
|
||||
// treat the numbers after 'E' or 'e' are in the exponential part.
|
||||
if iter.peek().map_or(false, |&exp: &char| exp == 'E' || exp == 'e') {
|
||||
// Consume 'E' or 'e'.
|
||||
iter.next();
|
||||
let exp_sign = if iter.peek().map_or(false, |&sign: &char| sign == '+' || sign == '-') {
|
||||
if iter.next().unwrap() == '-' { -1. } else { 1. }
|
||||
} else {
|
||||
1.
|
||||
};
|
||||
|
||||
let mut exp: f64 = 0.;
|
||||
while iter.peek().map_or(false, |n: &char| n.is_ascii_digit()) {
|
||||
exp = exp * 10. + iter.next().unwrap().to_digit(10).unwrap() as f64;
|
||||
}
|
||||
|
||||
value *= f64::powf(10., exp * exp_sign);
|
||||
}
|
||||
|
||||
if value.is_finite() {
|
||||
Ok(value.min(::std::f32::MAX as f64).max(::std::f32::MIN as f64) as CSSFloat)
|
||||
} else {
|
||||
Err(())
|
||||
}
|
||||
}
|
||||
|
||||
/// Skip all svg whitespaces, and return true if |iter| hasn't finished.
|
||||
#[inline]
|
||||
fn skip_wsp(iter: &mut Peekable<Chars>) -> bool {
|
||||
// Note: SVG 1.1 defines the whitespaces as \u{9}, \u{20}, \u{A}, \u{D}.
|
||||
// However, SVG 2 has one extra whitespace: \u{C}.
|
||||
// Therefore, we follow the newest spec for the definition of whitespace,
|
||||
// i.e. \u{9}, \u{20}, \u{A}, \u{C}, \u{D}, by is_ascii_whitespace().
|
||||
while iter.peek().map_or(false, |c: &char| c.is_ascii_whitespace()) {
|
||||
iter.next();
|
||||
}
|
||||
iter.peek().is_some()
|
||||
}
|
||||
|
||||
/// Skip all svg whitespaces and one comma, and return true if |iter| hasn't finished.
|
||||
#[inline]
|
||||
fn skip_comma_wsp(iter: &mut Peekable<Chars>) -> bool {
|
||||
if !skip_wsp(iter) {
|
||||
return false;
|
||||
}
|
||||
|
||||
if *iter.peek().unwrap() != ',' {
|
||||
return true;
|
||||
}
|
||||
iter.next();
|
||||
|
||||
skip_wsp(iter)
|
||||
}
|
||||
Loading…
Add table
Add a link
Reference in a new issue