Add polygons to draw filled polygons

gnuplot/Cargo.toml

@@ -120,6 +120,11 @@ path = "examples/multiple_axes.rs"
 name = "text"
 path = "examples/text.rs"
 
+[[example]]
+
+name = "polygons"
+path = "examples/polygons.rs"
+
 [dependencies]
 byteorder = "1.4.3"
 tempfile = "3.9"

gnuplot/examples/common.rs

@@ -1,4 +1,5 @@
 // This file is released into Public Domain.
+#![allow(dead_code)]
 use argparse_rs::*;
 use gnuplot::*;
 use std::env;

gnuplot/examples/polygons.rs

@@ -0,0 +1,48 @@
+// This file is released into Public Domain.
+use crate::common::*;
+use gnuplot::*;
+
+mod common;
+
+fn example(c: Common)
+{
+	let coords = [[0., 0.], [1., 1.], [2., 0.5], [2., -0.5], [1., -1.]];
+
+	let mut fg = Figure::new();
+	fg.set_title("Polygons");
+
+	let ax = fg.axes2d();
+	ax.polygon(
+		coords.iter().map(|x| x[0]),
+		coords.iter().map(|x| x[1]),
+		&[],
+	);
+
+	ax.polygon(
+		coords.iter().map(|x| x[0] + 2.),
+		coords.iter().map(|x| x[1]),
+		&[FillAlpha(0.), BorderColor("black"), LineWidth(4.)],
+	);
+	ax.polygon(
+		coords.iter().map(|x| x[0]),
+		coords.iter().map(|x| x[1] + 2.),
+		&[Color("#FF0000"), BorderColor("black"), LineWidth(4.)],
+	);
+	ax.polygon(
+		coords.iter().map(|x| x[0] + 2.),
+		coords.iter().map(|x| x[1] + 2.),
+		&[
+			FillPattern(Fix(BigCrosses)),
+			Color("#FF0000"),
+			BorderColor("black"),
+			LineWidth(4.),
+			LineStyle(Dash),
+		],
+	);
+	c.show(&mut fg, "polygons");
+}
+
+fn main()
+{
+	Common::new().map(|c| example(c));
+}

gnuplot/src/axes2d.rs

@@ -607,6 +607,36 @@ impl Axes2D
 		self
 	}
 
+	// Plot a polygon given coordinates of its vertices.
+	//
+	// # Arguments
+	// * `x` - x coordinates of the vertices
+	// * `y` - y coordinates of the vertices
+	// * `options` - Array of PlotOption<&str> controlling the appearance of the plot element. The relevant options are:
+	//	   * `Caption` - Specifies the caption for this dataset. Use an empty string to hide it (default).
+	//	   * `FillAlpha` - Sets the transparency of the filled region
+	//	   * `Color` - Sets the color of the filled region (and the border, unless `BorderColor` is set)
+	//	   * `BorderColor` - Sets the color of the border
+	//	   * `FillPattern` - Sets the fill pattern
+	pub fn polygon<
+		'l,
+		Tx: DataType,
+		X: IntoIterator<Item = Tx>,
+		Ty: DataType,
+		Y: IntoIterator<Item = Ty>,
+	>(
+		&'l mut self, x: X, y: Y, options: &[PlotOption<&str>],
+	) -> &'l mut Self
+	{
+		self.common.elems.push(PlotElement::new_plot2(
+			Polygons,
+			x,
+			y,
+			options.to_one_way_owned(),
+		));
+		self
+	}
+
 	/// Plot a 2D scatter-plot using boxes of automatic width. Box widths are set so that there are no gaps between successive boxes (i.e. each box may have a different width).
 	/// Boxes start at the x-axis and go towards the y value of the datapoint.
 	/// # Arguments

gnuplot/src/axes_common.rs

@@ -6,7 +6,6 @@ use self::DataSourceType::*;
 
 pub use self::LabelType::*;
 pub use self::PlotType::*;
-pub use self::TickAxis::*;
 use crate::coordinates::*;
 
 use crate::datatype::*;
@@ -305,6 +304,7 @@ impl PlotElement
 			XErrorBars => "xerrorbars",
 			YErrorBars => "yerrorbars",
 			FillBetween => "filledcurves",
+			Polygons => "polygons",
 			Boxes => "boxes",
 			BoxAndWhisker => "candlestick",
 			Pm3D => "pm3d",
@@ -352,13 +352,15 @@ impl PlotElement
 
 			if !is_pattern
 			{
-				writer.write_str("transparent solid ");
+				writer.write_str("transparent solid");
+				let mut alpha = 1.;
 				first_opt! {self.options,
 					FillAlpha(a) =>
 					{
-						write!(writer, "{:.12e}", a);
+						alpha = a;
 					}
 				}
+				write!(writer, " {:.12e}", alpha);
 			}
 
 			if self.plot_type.is_line()
@@ -725,6 +727,7 @@ pub enum PlotType
 	XErrorBars,
 	YErrorBars,
 	FillBetween,
+	Polygons,
 	Boxes,
 	BoxAndWhisker,
 	Pm3D,
@@ -737,7 +740,7 @@ impl PlotType
 	{
 		matches!(
 			*self,
-			Lines | LinesPoints | XErrorLines | Boxes | YErrorLines | BoxAndWhisker
+			Lines | LinesPoints | XErrorLines | Boxes | YErrorLines | BoxAndWhisker | Polygons
 		)
 	}
 
@@ -751,7 +754,7 @@ impl PlotType
 
 	fn is_fill(&self) -> bool
 	{
-		matches!(*self, Boxes | FillBetween | BoxAndWhisker)
+		matches!(*self, Boxes | FillBetween | BoxAndWhisker | Polygons)
 	}
 }