GRASS and Paraview

3D visualization of GRASS data with Paraview

Download Paraview at http://www.paraview.org (available for Linux, MacOSX and MS-Windows) (screenshot gallery)

2D/3D Raster/voxel export

GRASS GIS is one of the few GIS with volume data support. Here data are stored as a 3D raster with a unit volume called a voxel (volume pixel). Voxels are designed to support for example representations of trivariate continuous fields.

• 2D raster maps: r.out.vtk
• 3D raster (voxel) maps: r3.out.vtk

2D/3D Vector export

• 2D/3D vector maps: v.out.vtk

Visualization

Start Paraview, load the VTK data,... it is fairly intuitive to use. (don't hesitate to expand this part)

paraview --data=/tmp/threelayer.vtk

3D groundwater flow

3D groundwater flow

RGB visualization

Data export with r.out.vtk:

r.out.vtk input=dsm_s_michele elevation=dsm_s_michele \
          rgbmaps=ofd_s_michele.red,ofd_s_michele.green,ofd_s_michele.blue \
          out=s_michele_color.vtk

Load into Paraview:

paraview --data=s_michele_color.vtk

• In Paraview, click "Apply"
• Select the "Display" tab and choose "Color by" to switch from input scalars to rgb scalars
• Disable the "Map Scalars" check button in the display tab to avoid the use of a lookup table

Fondazione Mach - S. Michele (Italy) area shown in ParaView

Shown as stereo anaglyphs

paraview --stereo --data=s_michele_color.vtk

• In Paraview, click "Apply"
• Select the "Display" tab and choose "Color by" to switch from input scalars to rgb scalars
• Disable the "Map Scalars" check button in the display tab to avoid the use of a lookup table

Fondazione Mach - S. Michele (Italy) area shown in ParaView's stereo mode

Creating Stereo anaglyphs

• see Stereo anaglyphs

See also

• GRASS 3D Workshop -- 3D data visualization with VTK: PDF handouts (S. Gebbert)
• Video tutorials: r3.out.vtk Tutorial in four parts (S. Gebbert)
• GRASS and VTK related screenshots (S. Gebbert)