ENH: geometry from point sets and images

[glyg]

Geometry from sets of points:

• The from_voronoi2d function is 2D in 2D only, so we need to investigate
  how to retrieve a Sheet dataset from a set of 2D data points (here the face centers) in 3D
• retrieve junctions graph from a clean segmented image (watershed) in 2D
  • generate mockups
  • see whether some style of 2D in 3D generalisation is accessible

Feature extraction from an image (SIFT/SURF like):

From Steven Leach on linkedin

If you want quicker response I suggest WillowGarage ORB 30 FPS

• https://www.willowgarage.com/sites/default/files/orb_final.pdf
• http:https://stackoverflow.com/questions/7232651/how-does-opencv-orb-feature-detector-work
• http:https://opencv-users.1802565.n2.nabble.com/how-to-use-the-ORB-descriptor-td6606424.html

[glyg]

We'll work on this with Florian Bugarin student, so set to latter milestone

[glyg]

#136 brought the sheet_from_cell_centers function and the normals option for extrude so we're getting closer to that