# Show how to visualise a 2D function using Python code
# @author Sergei Chekanov 

from jv.geom import PgElementSet
from jhplot import HJavaView
from java.lang import Math
from math import *

geom = PgElementSet(3)
geom.setName("2D function")
# Set number of lines in x and y directions.
numXLines,numYLines = 50,50

def func(X,Y): # define some function in 2D using Python syntax 
    return 10*sin(sqrt(X*X+Y*Y))/sqrt(X*X+Y*Y);

# ranges in X and Y
xMin,xMax=-10.,10
yMin,yMax=-10.,10
zMin,zMax=0,10

geom.setNumVertices(numXLines*numYLines) # Allocate space for vertices

ind = 0 # Compute the vertices
x=xMin;
for i in xrange(numXLines):
      x = xMin + i*(xMax-xMin)/(numXLines-1)
      for j in xrange(numYLines):
         y = yMin + j*(yMax-yMin)/(numYLines-1)
         geom.setVertex(ind, x, y, func(x,y))
         ind=ind+1
# Compute connectivity of a rectangular mesh.
geom.makeQuadrConn(numXLines, numYLines)
geom.makeElementColorsFromXYZ() # add color and transparancy  
geom.showElementColors(True)
geom.setTransparency(0.5);
geom.showTransparency(True);

# show everythin 
c1= HJavaView()
c1.draw(geom)
view=c1.getView()
disp=view.getDisplay()
disp.showAxes(True)
disp.showBndBox(True);
c1.visible()