Grids on Polysurfaces

Currently it is difficult to operate on polysurfaces in grasshopper as there is no straight forward way to divide them into a grid as you would a single untrimmed surface. I have been experimenting with the workflow from maya nurbs to rhino to grasshopper, and as such have developed this method for creating an approximate grid over polysurfaces which keeps the individual surface information. The first step is to extract the size of your geometry in order to draw sectioning planes.

This geometry is referenced in to grasshopper and used to draw a section line as shown in the image above. We then extract the faces and graft them in order to keep this information stored in the dataTree. I have added simplify components to ensure that the tree structure is one dimensional {a} in order to make remapping later as simple as possible.

You can then section each of your surfaces using the brep/plane method. These curves are then cleaned to remove null values and remapped to keep only the relevant surface information in the dataTree. Dividing these curves gives you an approximate grid in the direction of each curve, creating points which can then be remapped and directly pulled back to each surface to find UV coordinates. With these you can finally place an evaluate surface component on the canvas to generate the required frames.

UPDATE: The definition is now uploaded

Poly Surface Grid.

~ by ledatomica on March 28, 2010.