Add a new flexible way to specify colors.

Fixes #105 #86

Author: etfrogers

gnuplot/Cargo.toml

@@ -62,6 +62,16 @@ path = "examples/box_xy_error.rs"
 
 [[example]]
 
+name = "color"
+path = "examples/color.rs"
+
+[[example]]
+
+name = "variable_color"
+path = "examples/variable_color.rs"
+
+[[example]]
+
 name = "lines_3d"
 path = "examples/lines_3d.rs"
 

gnuplot/examples/box_and_whisker.rs

@@ -27,7 +27,7 @@ fn example(c: Common)
 			[0.5f32, 0.25, 0.125].iter(),
 			&[
 				WhiskerBars(0.5),
-				Color("blue"),
+				Color("blue".into()),
 				LineWidth(2.0),
 				LineStyle(SmallDot),
 				FillAlpha(0.5),

gnuplot/examples/box_xy_error.rs

@@ -25,7 +25,7 @@ fn example(c: Common)
 			[-1.5f32, 4.5, 3.0].iter(),
 			[0.5f32, 4.75, 0.125].iter(),
 			&[
-				Color("blue"),
+				Color("blue".into()),
 				LineWidth(2.0),
 				LineStyle(SmallDot),
 				FillAlpha(0.5),

gnuplot/examples/color.rs

@@ -0,0 +1,140 @@
+use std::{fmt::Debug, iter};
+
+// This file is released into Public Domain.
+use crate::common::*;
+use gnuplot::*;
+
+mod common;
+
+fn color_name<T: Debug>(color: &PlotOption<T>) -> String
+{
+	match color
+	{
+		Color(color_type) => format!("{:?}", color_type),
+		_ => panic!(),
+	}
+}
+
+fn example(c: Common)
+{
+	let x = 0..5;
+
+	let colors = [
+		Color("black".into()),                    // Conversion to RGBString is implicit
+		Color(ColorType::RGBString("black")),     // Explicit use of RGBString
+		Color("red".into()),                      // Conversion to RGBString is implicit
+		Color(RGBString("#ff0000")),              // red using Hex coded RRGGBB
+		Color(RGBString("#00ff0000")),            // red using Hex coded AARRGGBB
+		Color("#ff8888".into()), // pink using Hex coded RRGGBB. Conversion to RGBString is implict
+		Color("#88ff0000".into()), // pink using Hex coded AARRGGBB. Conversion to RGBString is implict
+		Color(ColorType::RGBString("#ffff0000")), // transparent using Hex coded AARRGGBB
+		Color((128, 0, 255).into()), // purple using implict RGBInteger
+		Color(RGBInteger(128, 0, 255)), // purple using explict RGBInteger
+		Color((0.5, 0.0, 1.0).try_into().unwrap()), // purple using implict float to int conversion
+		Color((128, 128, 0, 255).into()), // pale purple using implict ARGBInteger
+		Color(ARGBInteger(128, 128, 0, 255)), // pale purple using explict ARGBInteger
+		Color((0.5, 0.5, 0.0, 1.0).try_into().unwrap()), // pale purple using implict float to int conversion
+	];
+
+	let mut fg = Figure::new();
+	let ax = fg.axes2d();
+	ax.set_title(
+		"Demo of RGBString in various forms\nSee code comments for how to construct the colors",
+		&[],
+	)
+	.set_x_range(Fix(-9.0), Auto)
+	.set_legend(Graph(0.5), Graph(0.9), &[], &[Font("", 14.0)]);
+
+	let n_colors = colors.len();
+	for (i, color) in colors.into_iter().enumerate()
+	{
+		ax.box_xy_error_delta(
+			x.clone(),
+			iter::repeat((n_colors - 1) - i),
+			iter::repeat(0.4),
+			iter::repeat(0.2),
+			&[
+				Caption(&color_name(&color)),
+				LineWidth(1.0),
+				BorderColor("black".into()),
+				color,
+			],
+		);
+	}
+
+	// Draw line across the boxes in fixed black and background colors
+	ax.lines(
+		[0, 0],
+		[0, n_colors - 1],
+		&[
+			LineWidth(7.0),
+			Color(Black),
+			Caption(&color_name::<String>(&Color(Black))),
+		],
+	);
+
+	ax.lines(
+		[4, 4],
+		[0, n_colors - 1],
+		&[
+			LineWidth(7.0),
+			Color(Background),
+			Caption(&color_name::<String>(&Color(Background))),
+		],
+	);
+
+	// any of the forms used for Color can also be used with TextColor and BorderColor
+	ax.set_x_label(
+		"Labels can be colored using the TextColor function",
+		&[TextColor((128, 0, 255).into())],
+	);
+
+	c.show(&mut fg, "rgb_color");
+
+	// ########################################################################
+
+	let mut fg = Figure::new();
+	let ax = fg.axes2d();
+	let max_cb = 10.0;
+	ax.set_cb_range(Fix(0.0), Fix(max_cb));
+	for color_value in 0..=10
+	{
+		let color_float = color_value as f64;
+		let frac_color = Color(PaletteFracColor(color_float / max_cb));
+		let cb_range_color = Color(PaletteCBColor(color_float));
+
+		ax.box_xy_error_delta(
+			[color_value],
+			[0],
+			[0.4],
+			[0.4],
+			&[
+				Caption(&color_name(&frac_color)),
+				LineWidth(1.0),
+				BorderColor("black".into()),
+				frac_color,
+			],
+		)
+		.box_xy_error_delta(
+			[color_value],
+			[1],
+			[0.4],
+			[0.4],
+			&[
+				Caption(&color_name(&cb_range_color)),
+				LineWidth(1.0),
+				BorderColor("black".into()),
+				cb_range_color,
+			],
+		);
+	}
+	ax.set_x_range(Fix(-10.0), Fix(11.0))
+		.set_y_range(Fix(-0.5), Fix(1.5))
+		.set_legend(Graph(0.45), Graph(0.9), &[], &[Font("", 14.0)]);
+	c.show(&mut fg, "palette_colors");
+}
+
+fn main()
+{
+	Common::new().map(|c| example(c));
+}

gnuplot/examples/dash_type.rs

@@ -22,7 +22,7 @@ fn example(c: Common)
 			x.clone().map(|v| v * 2 + 2 * i),
 			&[
 				LineWidth(2.),
-				Color("black"),
+				Color("black".into()),
 				LineStyle(dt),
 				Caption(&format!("{:?}", dt)),
 			],