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Weekly Report #07 - Silhouette Operator

I made some good progress this week. Last week I decided to rework the geometry generation of the silhouette operator.

The unified interpolation Method

The major advantage of the new system is a unified interpolation method. The method decides the shape of the object in the 3 Axis which is not defined by the sculptor. Therefore i can easily control the whole output by altering this method. Currently it controls the smoothness and depth of the generated geometry. The smoothness is a value between 0 and 1. With 0 being an object with sharp edges. If you draw a circle for example this result in a cylinder. A smoothness value of 1 will smooth out the corner and results in a sphere.

Order of Generation

Before the rework the different parts were relying on each other. In other words, i generated tube-parts first carried bordering edges/vertices over and generated T-intersections as well as Cap-parts afterwards. Due to this dependency i had to incorporate a lot of corner cases and experienced a lot of unexpected behaviour. With the new system every part is self-contained and exposes only one continuous edgeloop. This makes it easier to track done errors and is a cleaner approach in general.

Connecting the Parts

With those continuous edgeloops it is easier now to connect the different parts. There is still some issues with the general orientation of some parts and inverted edgeloops. But that should not be a big problem to solve.

What is the current stage?

In theory the geometry is now completely generated. The algorithm itself is done! In practice there are still a lot of issues with the system. As mentioned above the part orientation is messed up sometimes resulting in errors on the connections.

What is up next?

Next step is to fix the issues and make the tool a little more stable. After that i will try to fix the normal orientation. Currently if drawn counterclockwise it is correctly oriented and if drawn clockwise the normals need to be flipped. If the silhouette is more stable I will start exposing the tool settings and hopefully move on soon to connecting to existing geometry.