Add support to write plot objects in SVG format - gsl-shell.git - gsl-shell

diff --git a/agg-plot/draw_svg.cpp b/agg-plot/draw_svg.cpp
new file mode 100644
index 00000000..a86da5b1
--- /dev/null
+++ b/agg-plot/draw_svg.cpp

@@ -0,0 +1,63 @@

+#include "agg_color_rgba.h"

+

+#include "draw_svg.h"

+

+const char *svg_path_property_name[] = {"stroke-dasharray"};

+

+void format_rgb(char rgbstr[], agg::rgba8 c)

+{

+ sprintf(rgbstr, "#%02X%02X%02X", (int)c.r, (int)c.g, (int)c.b);

+}

+

+static void append_properties(str& s, svg_property_list* properties)

+{

+ for (svg_property_list* p = properties; p; p = p->next())

+ {

+ svg_property_item& item = p->content();

+ const char* name = svg_path_property_name[item.key];

+ s.printf_add(";%s:%s", name, item.value);

+ }

+}

+

+str svg_stroke_path(str& path_coords, double width, int id, agg::rgba8 c,

+ svg_property_list* properties)

+{

+ char rgbstr[8];

+ format_rgb(rgbstr, c);

+

+ str s = str::print("<path d=\"%s\" "

+ "id=\"path%i\" "

+ "style=\"fill:none;stroke:%s;"

+ "stroke-width:%gpx;stroke-linecap:butt;"

+ "stroke-linejoin:miter",

+ path_coords.cstr(), id, rgbstr, width);

+

+ if (c.a < 255) {

+ double alpha = (double)c.a / 255;

+ s.printf_add(";stroke-opacity:%g", alpha);

+ }

+

+ append_properties(s, properties);

+ s.append("\" />");

+

+ return s;

+}

+

+str svg_fill_path(str& path_coords, int id, agg::rgba8 c,

+ svg_property_list* properties)

+{

+ char rgbstr[8];

+ format_rgb(rgbstr, c);

+

+ double alpha = (double)c.a / 255;

+

+ str s = str::print("<path d=\"%s\" "

+ "id=\"path%i\" "

+ "style=\"fill:%s;fill-opacity:%g;stroke:none\" />",

+ path_coords.cstr(), id, rgbstr, alpha);

+

+ append_properties(s, properties);

+ s.append("\" />");

+

+ return s;

+}