Re: Python & OpenGL geometry

Hi Michal,

 >box1 = ROOT.gGeoManager.MakeBox('box1', solid1, 10, 20, 30)  >box2 = ROOT.gGeoManager.MakeBox('box2', solid1, 20, 20, 20)

Looks for me the 2 volumes have the same medium, therefore material. Try   solid2 for the second line. Also, create a TGeoManager using:

ROOT.TGeoManager('geom','comment')

Cheers,
Andrei

Michal Dwuznik wrote:
> Hi,
>
> I got a bit strange behaviour using python with ROOT geometry & OpenGL
> classes, minimum example follows:
>
> import ROOT
> ROOT.TGeoManager()
> vac = ROOT.TGeoMaterial('vac')
> sol1 = ROOT.TGeoMaterial('sol1')
> sol2 = ROOT.TGeoMaterial('sol2')
> vacuum = ROOT.TGeoMedium('vacuum', 1, vac)
> solid1 = ROOT.TGeoMedium('solid1', 1, sol1)
> solid2 = ROOT.TGeoMedium('solid2', 1, sol2)
> top = ROOT.gGeoManager.MakeBox('top' , vacuum, 100, 100, 100)
> box1 = ROOT.gGeoManager.MakeBox('box1', solid1, 10, 20, 30)
> box2 = ROOT.gGeoManager.MakeBox('box2', solid1, 20, 20, 20)
> box2.SetLineColor(ROOT.kYellow)
> ROOT.gGeoManager.SetTopVolume(top)
> top.AddNode(box1, 1)
> top.AddNode(box2, 2)
> ROOT.gGeoManager.CloseGeometry()
> ROOT.gGeoManager.GetTopVolume().Draw('ogl')
> #two boxes visible, overlapping, default and yellow colour, as expected
> vols = [i for i in ROOT.gGeoManager.GetListOfUVolumes()]
> b1 = vols[-2]
> print b1.GetName()
> b2 = vols[-1]
> print b2.GetName()
> whatever = raw_input("Press Enter")
> ROOT.gPad.GetViewer3D().UpdateScene()
> b1.SetTransparency(80)
> # Changing the transparency of _one_ of the two boxes
> b1.SetLineColor(ROOT.kGreen)
> # and colour for one, too
> ROOT.gPad.GetViewer3D().UpdateScene()
> # The result on i810 notebook is a bit different from expectations
> # one box has colour changed to green (expected)
> # and _both_ boxes made of different media/material are transparent
> # instead of one
> whatever = raw_input("Press Enter")
> p1 = ROOT.gGeoManager.MakePhysicalNode('/top_1/box1_1')
> p2 = ROOT.gGeoManager.MakePhysicalNode('/top_1/box2_2')
> p=[i for i in ROOT.gGeoManager.GetListOfPhysicalNodes()]
> p[0].Align(ROOT.TGeoTranslation(10,0,0))
> p[1].Align(ROOT.TGeoTranslation(0,30,0))
> ROOT.gPad.GetViewer3D().UpdateScene()
> # Ok, aligning the nodes works ok, the boxes move around as expected, but
> whatever = raw_input("Press Enter")
> b1.SetLineColor(ROOT.kWhite)
> b1.SetTransparency(0)
> ROOT.gPad.GetViewer3D().UpdateScene()
> # is no longer changing the attributes of visible boxes...
> #Transparency changes, again for _both_ volumes
> #colour does not - b1 is still green, not white.
> #I would expect both functions to work, or both to fail
> #recreating the volume references 'just in case'
> whatever = raw_input("Press Enter")
> vols = [i for i in ROOT.gGeoManager.GetListOfUVolumes()]
> b1 = vols[-2]
> print b1.GetName()
> b2 = vols[-1]
> print b2.GetName()
> b1.SetLineColor(ROOT.kCyan)
> b1.SetTransparency(0)
> #does not help at all
> Could someone pinpoint my mistake?
> Regards
> Michal
>
> PS:Sorry if double posting
>
Received on Fri Jul 18 2008 - 10:37:41 CEST