Feature vertices

Feature vertices are extra vertices added to branch geometry to ensure that areas of high contrast displacement have enough geometry to capture the detail.

To add feature vertices, paint them on by hand or add them via the branch material. The image below shows how feature vertices are used to add displacement detail on a branch.

To better understand why these vertices are necessary, consider the heightmap in the following shot:

Without feature vertices, the only way to be sure to capture those displacement details is to use a very high number of length and radial segments on the branches. Doing so will capture the features by applying a dense, uniform grid of vertices across the whole branch. The details will be captured but the resulting polygon count is almost always much too high.

By using feature vertices, extra vertices are added precisely where they are needed. The following image shows the same shot with and without feature vertices.