DMelt:Plots/VisAd
VisAd
DataMelt includes VisAd, which was destined by programmers at the University of Wisconsin Space Science and Engineering Center (SSEC). We reproduce its guide in VisAd guide section
The Java API is given by visad package.
VisAd tutorial
Here is a short tutorial how to visualize numerical information using interactive canvas called jhplot.HVisAd.
We will show step-by step example, starting from elementary operation, such as opening the canvas and creating a 3D scene.
from jhplot import * from java.awt import * c1 = HVisAd("VisAd",600,600) # make 600x600 canvas display = c1.getDisplay() # get display ren=c1.getRender() # get display render ren.setBoxOn(True) # draw a box ren.setBackgroundColor(Color.white) # make it white c1.visible() # show it
Next, we will try to manipulate with the box. For example, we can zooming (or zoom out), move it and rotate:
from jhplot import * c1 = HVisAd("VisAd",600,600) ren=c1.getRender() ren.setBoxOn(True) c1.setScaling(0.8) c1.setRotation(0,20,0) # rotation around Y in 20 deg c1.setTranslation(0.1,0.0,0.0) # shift in X by 10% c1.visible() # show it
You can use full Java API of VisAd to archive scaling and rotations using the "ProjectionControl" method:
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So far we had just a box. Now we can draw axises. Here is an example how to set axis, define their ranges
from jhplot import * c1 = HVisAd("VisAd") display=c1.getDisplay() cont=display.getGraphicsModeControl() cont.setSceneAntialiasingEnable(True) cont.setLineWidth(1) ren=c1.getRender(); ren.setBoxOn(True) # draw a box c1.setAxes("X",0,10,"Y",0,10,"Z",0,10) c1.visible() # show canvas
The method setAxes() takes the name of the axis, min and max value for X,Y,Z axis. Here is a more refined example that shows how to make custom frame with axis:
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VisAd code examples
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Using full VisAd Java api
Here is a Jython macro which shows ho to visualize 2D data calling Java classes directly:
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