[vtkusers] Re: Re: 3D Axes For User Orientation...

[Nick Hu]

Hi Andrea,

I made some changes to your python code, and now it looks right. But I don't
know too much detail about the "layer" stuff in the vtkRendererWindow, so I
don't know the cause of the previous pronlem.

The code:
import vtkpython
import Numeric

cone = vtkpython.vtkConeSource()
coneMapper = vtkpython.vtkPolyDataMapper()
coneMapper.SetInput(cone.GetOutput())
coneActor = vtkpython.vtkActor()
coneActor.SetMapper(coneMapper)

camAxes = vtkpython.vtkCamera()
camAxes.ParallelProjectionOn()

renAxes = vtkpython.vtkRenderer()
renAxes.InteractiveOff()
renAxes.SetActiveCamera(camAxes)
renAxes.SetViewport(0, 0, 0.25, 0.25)
#renAxes.SetLayer(0)

def SyncCameras(renderer, event_string):

    cam = ren.GetActiveCamera()
    camAxes.SetViewUp(cam.GetViewUp())
    proj = cam.GetDirectionOfProjection()
    x, y, z = cam.GetDirectionOfProjection()

    # figure out the distance away from 0 0 0
    # if the renderer resets the camera to optimally inlcude all props
    # composing the orientation marker

    bnds = renAxes.ComputeVisiblePropBounds()
    x0, x1, y0, y1, z0, z1 = renAxes.ComputeVisiblePropBounds()
    renAxes.ResetCamera(x0, x1, y0, y1, z0, z1)
    pos = camAxes.GetPosition()
    px, py, pz = camAxes.GetPosition()
    d = Numeric.sqrt(px*px + py*py + pz*pz)
    dproj = Numeric.sqrt(x*x + y*y + z*z)

    # reset the camera back along the unit vector of the
    # direction of projection using our optimal distance
    camAxes.SetFocalPoint(0,0,0)
    camAxes.SetPosition(-d*x/dproj, -d*y/dproj, -d*z/dproj)
    renAxes.ResetCameraClippingRange()



ren = vtkpython.vtkRenderer()
ren.AddActor(coneActor)
#renAxes.SetLayer(1)
ren.AddObserver("StartEvent", SyncCameras)

renWin = vtkpython.vtkRenderWindow()
#renWin.SetNumberOfLayers(2)

#renWin.AddRenderer(renAxes)
renWin.SetSize(600,600)
renWin.AddRenderer(ren)
renWin.AddRenderer(renAxes)
iren = vtkpython.vtkRenderWindowInteractor()
iren.SetRenderWindow(renWin)

## The corner axes
xAxis = vtkpython.vtkArrowSource()
xAxisMapper = vtkpython.vtkPolyDataMapper()
xAxisMapper.SetInput(xAxis.GetOutput())
xAxisActor = vtkpython.vtkActor()
xAxisActor.SetMapper(xAxisMapper)
xAxisActor.GetProperty().SetColor(1,0,0)

yAxis = vtkpython.vtkArrowSource()
yAxisMapper = vtkpython.vtkPolyDataMapper()
yAxisMapper.SetInput(yAxis.GetOutput())
yAxisActor = vtkpython.vtkActor()
yAxisActor.SetMapper(yAxisMapper)
yAxisActor.GetProperty().SetColor(1,1,0)
yAxisActor.RotateZ(90)

zAxis = vtkpython.vtkArrowSource()
zAxisMapper = vtkpython.vtkPolyDataMapper()
zAxisMapper.SetInput(zAxis.GetOutput())
zAxisActor = vtkpython.vtkActor()
zAxisActor.SetMapper(zAxisMapper)
zAxisActor.GetProperty().SetColor(0,1,0)
zAxisActor.RotateY(-90)

xLabel = vtkpython.vtkCaptionActor2D()
xLabel.SetCaption("X")
xLabel.SetAttachmentPoint(1,0,0)
xLabel.LeaderOff()
xLabel.BorderOff()
xLabel.SetPosition(0,0)

yLabel = vtkpython.vtkCaptionActor2D()
yLabel.SetCaption("Y")
yLabel.SetAttachmentPoint(0,1,0)
yLabel.LeaderOff()
yLabel.BorderOff()
yLabel.SetPosition(0,0)

zLabel = vtkpython.vtkCaptionActor2D()
zLabel.SetCaption("Z")
zLabel.SetAttachmentPoint(0,0,1)
zLabel.LeaderOff()
zLabel.BorderOff()
zLabel.SetPosition(0,0)

Axes3D = vtkpython.vtkPropAssembly()
Axes3D.AddPart(xAxisActor)
Axes3D.AddPart(yAxisActor)
Axes3D.AddPart(zAxisActor)
Axes3D.AddPart(xLabel)
Axes3D.AddPart(yLabel)
Axes3D.AddPart(zLabel)

renAxes.AddActor(Axes3D)

iren.Initialize()
iren.Start()



Nick
>
> 2) By translating (I hope correctly) the code from Goodwin Lawlor found at
this
> url:
>
> http://www.bioengineering-research.com/vtk/axes_example2.tcl
>
> I was able to create the orientation axes at the bottom left of the VTK
window,
> but I'm facing some strange behaviors. When I rotate the main Actor (a
Cone, in
> my example), I get a sequence of superimposing images that represent all
the
> rotation I have done on my cone. I can not explain it clearly, I've tried
to
> attach an image but the vtkuser server told me that it was too big, so I
posted
> an image explining what I said at this url:
>
> http://xoomer.virgilio.it/infinity77/vtkproblem.jpg
>
> It's a strange behavior, I don't know why it happens...
>
> I post here my python code, if someone has comments on this, please let me
> know... probably I have done something wrong in traslating it from tcl...
>
> Thank you for every suggestion.
>
> Andrea.
>
> # BEGIN PYTHON CODE
>
> import vtkpython
> import Numeric
>
> cone = vtkpython.vtkConeSource()
> coneMapper = vtkpython.vtkPolyDataMapper()
> coneMapper.SetInput(cone.GetOutput())
> coneActor = vtkpython.vtkActor()
> coneActor.SetMapper(coneMapper)
>
> camAxes = vtkpython.vtkCamera()
> camAxes.ParallelProjectionOn()
>
> renAxes = vtkpython.vtkRenderer()
> renAxes.InteractiveOff()
> renAxes.SetActiveCamera(camAxes)
> renAxes.SetViewport(0, 0, 0.25, 0.25)
> renAxes.SetLayer(1)
>
> def SyncCameras(renderer, event_string):
>
>     cam = ren.GetActiveCamera()
>     camAxes.SetViewUp(cam.GetViewUp())
>     proj = cam.GetDirectionOfProjection()
>     x, y, z = cam.GetDirectionOfProjection()
>
>     # figure out the distance away from 0 0 0
>     # if the renderer resets the camera to optimally inlcude all props
>     # composing the orientation marker
>
>     bnds = renAxes.ComputeVisiblePropBounds()
>     x0, x1, y0, y1, z0, z1 = renAxes.ComputeVisiblePropBounds()
>     renAxes.ResetCamera(x0, x1, y0, y1, z0, z1)
>     pos = camAxes.GetPosition()
>     px, py, pz = camAxes.GetPosition()
>     d = Numeric.sqrt(px*px + py*py + pz*pz)
>     dproj = Numeric.sqrt(x*x + y*y + z*z)
>
>     # reset the camera back along the unit vector of the
>     # direction of projection using our optimal distance
>     camAxes.SetFocalPoint(0,0,0)
>     camAxes.SetPosition(-d*x/dproj, -d*y/dproj, -d*z/dproj)
>     renAxes.ResetCameraClippingRange()
>
>
> ren = vtkpython.vtkRenderer()
> ren.AddActor(coneActor)
>
> ren.AddObserver("StartEvent", SyncCameras)
>
> renWin = vtkpython.vtkRenderWindow()
> renWin.SetNumberOfLayers(2)
> renWin.AddRenderer(renAxes)
> renWin.SetSize(600,600)
> renWin.AddRenderer(ren)
> iren = vtkpython.vtkRenderWindowInteractor()
> iren.SetRenderWindow(renWin)
>
> ## The corner axes
> xAxis = vtkpython.vtkArrowSource()
> xAxisMapper = vtkpython.vtkPolyDataMapper()
> xAxisMapper.SetInput(xAxis.GetOutput())
> xAxisActor = vtkpython.vtkActor()
> xAxisActor.SetMapper(xAxisMapper)
> xAxisActor.GetProperty().SetColor(1,0,0)
>
> yAxis = vtkpython.vtkArrowSource()
> yAxisMapper = vtkpython.vtkPolyDataMapper()
> yAxisMapper.SetInput(yAxis.GetOutput())
> yAxisActor = vtkpython.vtkActor()
> yAxisActor.SetMapper(yAxisMapper)
> yAxisActor.GetProperty().SetColor(1,1,0)
> yAxisActor.RotateZ(90)
>
> zAxis = vtkpython.vtkArrowSource()
> zAxisMapper = vtkpython.vtkPolyDataMapper()
> zAxisMapper.SetInput(zAxis.GetOutput())
> zAxisActor = vtkpython.vtkActor()
> zAxisActor.SetMapper(zAxisMapper)
> zAxisActor.GetProperty().SetColor(0,1,0)
> zAxisActor.RotateY(-90)
>
> xLabel = vtkpython.vtkCaptionActor2D()
> xLabel.SetCaption("X")
> xLabel.SetAttachmentPoint(1,0,0)
> xLabel.LeaderOff()
> xLabel.BorderOff()
> xLabel.SetPosition(0,0)
>
> yLabel = vtkpython.vtkCaptionActor2D()
> yLabel.SetCaption("Y")
> yLabel.SetAttachmentPoint(0,1,0)
> yLabel.LeaderOff()
> yLabel.BorderOff()
> yLabel.SetPosition(0,0)
>
> zLabel = vtkpython.vtkCaptionActor2D()
> zLabel.SetCaption("Z")
> zLabel.SetAttachmentPoint(0,0,1)
> zLabel.LeaderOff()
> zLabel.BorderOff()
> zLabel.SetPosition(0,0)
>
> Axes3D = vtkpython.vtkPropAssembly()
> Axes3D.AddPart(xAxisActor)
> Axes3D.AddPart(yAxisActor)
> Axes3D.AddPart(zAxisActor)
> Axes3D.AddPart(xLabel)
> Axes3D.AddPart(yLabel)
> Axes3D.AddPart(zLabel)
>
> renAxes.AddActor(Axes3D)
>
> iren.Initialize()
> iren.Start()
>
> # END PYTHON CODE
>