Step 3 - Adding Graphics

When you add an image to your HTML page, you just add a reference to the image, you don't actually add the image. In this step we will create an image and then add a reference to it in our HTML file.

N.B. It is important that the image is created before it is referenced in the HTML. It is possible that the web browser will request the image as soon as it finds the reference to it in the HTML. If this happens before the image has been created then the image will be broken.

We'll start with the framework.gsw file found in $UNIDIR/example/GsharpWE, which has been slightly modified to use the functions in libhtml.gsl:

#!/bin/GsharpWE

include "$UNIDIR/lib/libhtml.gsl";

#Step 1 - Echo Header
HTTPheader();

#Step 2 - Setup Variables


#Step 3 - Create Plot
echo("<!---");
exec("$UNIDIR/example/Gsharp/samples/barcharts.gsl");
echo("--->");

#Step 4 - Make Image
imgfile = "start"+getpid()+".gif";
make_image(708, 531, getenv("GsharpTmpFilesActualDir")+imgfile);

#Step 5 - Create HTML
HTMLheader(1, "My GsharpWE Plot", "AVS");

HTMLheading(1, 1, "My GsharpWE Plot");

HTMLrule(1,60);
HTMLimage(1, getenv("GsharpTmpFilesWebDir")+imgfile);
HTMLrule(1,60);

HTMLfooter(1);