Freestyle integration into Blender

July 12, 2010

Weekly update June 28-July 11

Filed under: Update — The dev team @ 12:54 AM

Since the last blog update, the dev team was working on the design and implementation of the new GUI framework (referred to as the Parameter Editor mode), while important updates in the trunk were merged and some compilation issues were fixed.

The Parameter Editor mode has now a set of UI controls for better specifying feature edge selection criteria.  The Freestyle tab in the Render buttons has a pair of radio buttons named Inclusive and Exclusive, as well as another pair of radio buttons named Logical AND and Logical OR.  The Inclusive button allows you to select feature edges that satisfy the given selection criteria, while Exclusive is to select those that do not satisfy the given conditions.  The Logical AND and Logical OR buttons are for combining selection criteria by logical “and” and “or” operations (i.e., logical conjunction and disjunction), respectively.  These UI controls allow you to easily select desired feature edges that will be fed to subsequent stroke rendering.

The trunk has recently adopted a new installation path structure, and the Freestyle branch has already incorporated the path changes.  For branch users, this means that standard style modules are installed in a different path.  Old paths in your blend files may need to be fixed manually.

In the mean time, Stéphane Grabli, one of the coauthors of the original Freestyle, kindly provided us with a set of patches for fixing bugs that existed in both the original Freestyle and the Blender Freestyle branch.  One of the fixes is concerned with stroke construction, which is now capable of generating better feature edge topology thanks to more robust visibility tests.  The improvement is salient when you look at external contours.  The following image shows a comparison of external contours generated by the old revision 29733 and the new improved revision 30169.  The red and blue colors are intended to show where each stroke starts and ends, respectively.  The old version generated 55 strokes, showing lots of stroke fragmentation.  The new version yielded only 22 strokes (most of them were out of the camera view), demonstrating a much better stroke quality.  Thank you Stéphane for the wonderful contributions!

In the next weeks, we are going to keep up the work on the new GUI stuff.  Additions of new UI controls into the Freestyle Line Style tab are planned.

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