J/Link MathCanvas/Graphics/Interaction
- To: mathgroup at smc.vnet.net
- Subject: [mg27173] J/Link MathCanvas/Graphics/Interaction
- From: murphee <werner.schuster at netway.at>
- Date: Fri, 9 Feb 2001 03:10:20 -0500 (EST)
- Sender: owner-wri-mathgroup at wolfram.com
yo Group (especially Todd Gayley), I am using the (magnificent) J/Link to do some interactive Mathematics; eg: Plot a graph (eg Sine curve) and a Point, and allow the user to grab the Point with the mouse and drag it along the graph; allright, doesnt sound like much, but it's just an example to make clear what I want to do; now, the Problem is, I can use the evaluateToImage,... methods to receive a Bitmap (in GIF Format) of the Plot from Mathematica, but what I would need would be the Position of the Objects in the Plot (in my example: Graph, Point) relative to the bitmap I receive from the evaluateToImage method, so I know when the mouse is "in" one of these objects (in order to know when the user wants to "grab" the object); currently, I cannot get this; I would have to guess the Position of the objects, but changing one Parameter in the Plot would make this guess useless again (and the whole thing couldn't be done dynamically); I haven't yet found a way in J/Link to do this, or am I just thinking in the wrong direction? if there is no simple solution available in J/Link, maybe that could be something for J/Link 2.0 ... since you're (you = J/Link Maintainers) at the "source" of the Production of the Bitmap, wouldn't it be possible to somehow extract/preserve these parameters and allow the user to access them; from what I know, you use the psrender.exe programm to render the PostScript output to the GIF file; maybe that could be a place to get that info from; I hope someone might help me here, Thanx in advance, murphee ************ my site: www.angelfire.com/co/werners a must: www.linuxtoday.com so is this: www.javaworld.com as well as: www.userfriendly.org/static ************ "... and the fact that I haven't put a gun to my mouth yet, makes me a winner!" Al Bundy