Banate CAD Second Release

There is a new consolidated package available here: Banate CAD 20111128

I wonder if a weekly distribution is a realistic thing to expect?

Banate CAD is maintained “Live” on GitHub, so changes that are going on in the code are reflected in GitHub fairly regularly. But, since it is live, things like the Examples get out of sync regularly as well. I am updating the Examples weekly to match the current state of the software for that week. When I bring the two in sync, I package it up in a convenient .zip and make it available for download.

This past week saw quite a lot of change in Banate CAD. Primarily, after the first release, I have been focused on reducing the amount of code that’s in the package. At the end of the day, I want the codesize to remain within about 256K. If it remains within that budget, then I have something that could possibly be hosted on a microcontroller, or other small compute devices. So far, on disk size is 133K, so I still have some room to add more functions.

One big form of reduction for this past week was further simplification and reuse of the core BiParametric object. It can be used to do anything from produce a sphere, to a Bezier surface. I also introduced the concept of “Sampler”, which is essentially just a function that you can ask “for this parametric position, what’s your value?”.

The MoonShot picture above is the epitomy of using these samplers. I use a sampler for the offsets of vertices, to do height mapping, and I use the same exact sampler to determine the color on a per facet basis. That makes for some very convenient reuse. It also demonstrates how easily samplers can be combined into super samplers.

Another usage of a functor has to do with the Torus object. The base torus on its own will only generate a circular profile. But, you can hand it a functor which will determine the outline of that profile. In this case, I’ve used the SuperEllipse formula to give shape to the profile. In this way, you can pretty much select any cross section profile you like. The core of the Torus routine remains the same, go around a ‘circle’. At some point, even that part will become a functor, and you’ll be able to generate very strange torii indeed.

As Banate CAD is meant to do ‘CAD’, I finally worked on getting the export to .stl function working properly.  Now, most models, if they are solids, can actually be exported.  The cheat at the moment is that they will always export to a file with the name “file.stl”.  There’s no reason for this other than I need to change file handling to be more robust in general, so I didn’t bother to make any attempt to improve it at the moment.  At the moment, although the .stl files will work, they certainly benefit from going through a tool like MeshLab to clean them up and remove bits and pieces, depending on the model.  Mainly removing duplicate vertices, and triangles of zero area, like at the poles of a sphere.

So, there you have it.  One week’s worth of work, and a whole bunch of new functionality.

---