Add a flag to save examples to images, for testing.

Also, disable the echoing by default.

gnuplot/examples/common.rs

@@ -3,6 +3,7 @@
 use argparse_rs::*;
 use gnuplot::*;
 use std::env;
+use std::path::Path;
 
 #[derive(Copy, Clone)]
 pub struct BetterIterator<'l, T: 'l>
@@ -41,8 +42,11 @@ impl<'l, T: 'l> BetterIteratorExt<'l, T> for &'l [T]
 pub struct Common
 {
 	pub no_show: bool,
+	pub save_png: bool,
 	pub term: Option<String>,
 	pub extension: String,
+	pub output_dir: String,
+	pub echo: bool,
 }
 
 impl Common
@@ -70,13 +74,37 @@ impl Common
 			ArgType::Option,
 		);
 		args.add_opt(
-			"extension",
+			"output-dir",
 			None,
+			'o',
+			false,
+			"output directory.",
+			ArgType::Option,
+		);
+		args.add_opt(
+			"extension",
+			Some("out"),
 			'e',
 			false,
 			"specify what extension the output file should have. Default: 'out'",
 			ArgType::Option,
 		);
+		args.add_opt(
+			"save-png",
+			Some("false"),
+			's',
+			false,
+			"render the plots to images.",
+			ArgType::Flag,
+		);
+		args.add_opt(
+			"echo",
+			Some("false"),
+			'g',
+			false,
+			"echo gnuplot commands.",
+			ArgType::Flag,
+		);
 
 		let res = args.parse(arg_vec.iter()).unwrap();
 
@@ -87,21 +115,36 @@ impl Common
 		}
 
 		Some(Common {
+			output_dir: res.get("output-dir").unwrap_or("".into()),
 			no_show: res.get("no-show").unwrap(),
+			save_png: res.get("save-png").unwrap(),
+			echo: res.get("echo").unwrap_or(false),
 			term: res.get::<String>("terminal").map(|s| s.to_string()),
-			extension: res.get::<String>("extension").unwrap_or("out".to_string()),
+			extension: res.get::<String>("extension").unwrap(),
 		})
 	}
 
 	pub fn show(&self, fg: &mut Figure, filename: &str)
 	{
+		let out_path = Path::new(&self.output_dir).join(filename);
 		self.term.as_ref().map(|t| {
-			fg.set_terminal(&t, &format!("{}.{}", filename, self.extension));
+			fg.set_terminal(
+				&t,
+				out_path.with_extension(&self.extension).to_str().unwrap(),
+			);
 		});
 		if !self.no_show
 		{
 			fg.show().unwrap();
 		}
-		fg.echo_to_file(&format!("{}.gnuplot", filename));
+		if self.save_png
+		{
+			fg.save_to_png(out_path.with_extension("png").to_str().unwrap(), 800, 600)
+				.unwrap();
+		}
+		if self.echo
+		{
+			fg.echo_to_file(out_path.with_extension("gnuplot").to_str().unwrap());
+		}
 	}
 }

gnuplot/examples/example1.rs

@@ -91,12 +91,6 @@ fn example(c: Common)
 
 	c.show(&mut fg, "example1_1");
 
-	if !c.no_show
-	{
-		fg.save_to_pdf("example1_1.pdf", 3.5, 3.5).unwrap();
-		fg.save_to_png("example1_1.png", 256, 256).unwrap();
-	}
-
 	let mut fg = Figure::new();
 
 	fg.axes2d()