Manual Flattening of a Surface
This page describes how to manually flatten a surface. If you
have used Caret to segment an MRI and produce your surface you should
use Surface->Flatten Full or Partial Hemisphere. A surface
that was created by reconstructing from contours is a type of surface
that needs to be manually flattened.
- Select Surface->Transform->Translate to
Center of
Mass.
- Rotate the surface and
find a location in the surface that you
would like to see at the center of of flat surface when the flat
surface is created. Place this location at the center of the main
window facing towards you.
- Select Surface->Transform->Apply Current View.
Uncheck Apply Scaling but leave Apply Translation and Apply Rotation
selected. Press the OK button.
- Select File->Save Data File and save the
coordinate file by
adding "oriented" into its name.
- Select Surface->Geometry->Inflate Surface.
Set Smoothing Iterations to
500, Inflate Every X Iterations
to 10, and Inflation Factor to
2.0. Press the OK
button. This
operation will take several minutes. This operation will start to
unfold the surface. If the surface still has folding and is not
spherical after this operation, repeat this operation.
- Select File->Save Data File and save the
coordinate file by
adding "inflated" into its name.
- Select Surface->Geometry->Convert to Sphere
which will
force the surface to become a sphere.
- Select File->Save Data File and save the
coordinate file by
adding "sphere" into its name.
- Select Surface->Geometry->Compress Front Face.
Set
the compression factor to 0.5
and press the OK button.
- Select File->Save Data File and save the coordinate file by
adding "compressed" into its name.
- Select File->Geometry->Project Sphere to Flat.
- Select File->Save Data File and save the coordinate file by
adding "initial_flat" into its name.
- Select Surface->Topology->Remove Corner and
Straggler
Tiles. Check the
Delete Corners and Stragglers
radio button.
- Select File->Save Data File and save the coordinate file by
adding "initial_flat_cleaned" into its name.
- Select File->Save Data File and save the topology file by
adding "cut" into its name.
- Select Surface->Measurements->Crossover Check.
Areas
of crossovers, shown in red, may be removed by drawing and applying
cuts. If cuts are applied, be sure to use the topology menu to
remove islands and save the coordinate and topology files.
- Use the Spec Button in
the Toolbar to load the
original surface
that you started using at the beginning of this procedure if it is not
already loaded.
- Select Surface->Morphing->Mult-Resolution
Morphing Flat
Surface. Set the
Reference to the original
surface and Morphing
to your the flat surface. Set
the number of cycles to 1 and press
the Run button. Repeat
this step as needed to reduce distortion
in the surface.
- Select File->Save Data File and save the coordinate file by
adding "flat_final" into its name.