I am developing open source MeteoInfo sotware with 3D plot function powered by JOGL (

https://github.com/meteoinfo/MeteoInfo). For 3D contourf function, GLUtessellator was used for polygon tessellation (

https://github.com/meteoinfo/MeteoInfo/tree/master/meteoinfo-chart/src/main/java/org/meteoinfo/chart/jogl/tessellator). Every thing is ok when the contour filled polygons perpendicular to z axis, even the polygons with holes.

Same polygons with y fixed, so the polygons parallel with z axis, can not be visulized correct.

Any idea on it? Thanks!

The MeteoInfoLab scripts (Jython language) for test:

*fn = os.path.join(migl.get_sample_folder(), 'GrADS', 'model.ctl')
*

f = addfile(fn)

ps_z = f['U'][0,2,:,'0:180']

#Plot

ax = axes3d()

grid(False)

geoshow('continent', facecolor=(255,229,181), edgecolor='b', linewidth=1)

ax.contourf(ps_z, 10, offset=3, zdir='z', edgecolor='gray', alpha=0.8)

colorbar()

xlim(0, 180)

xlabel('Longitude')

ylabel('Latitude')

title('contourf z fixed')-----------------------------------------------------------------------------------

*fn = os.path.join(migl.get_sample_folder(), 'GrADS', 'model.ctl')
*

f = addfile(fn)

ps_z = f['U'][0,1,:,'0:180']

#Plot

ax = axes3d()

grid(False)

geoshow('continent', facecolor=(255,229,181), edgecolor='b', linewidth=1,

offset=-90)

ax.contourf(ps_z, 10, offset=0, zdir='y', edgecolor='gray', alpha=0.8)

colorbar()

xlim(0, 180)

xlabel('Longitude')

ylabel('Latitude')

title('contourf y fixed')