David, The Wiki section on submitting patches might be of assistance: http://wiki.blender.org/index.php/Dev:Doc/Process/Patches#Submitting_Patches
Nick On Tue, Jun 18, 2013 at 4:27 PM, <dl...@me.com> wrote: > Hello again. I am hoping to get a response this time now that things seem > to have quieted down some on the list. I've got a patch that modifies the > lattice deformer ever so slightly...it simply adds a new spline option. > More info is below. this is a very minor change and I hope it can be > accepted and integrated quickly. We are using Blender at NASA Ames as an > engineering tool, something many of you may never have expected. However, > the lattice deformer is great for doing shape optimization on triangulated > surfaces of airplanes and other aerospace geometries. currently I am using > Blender to do aerostructural analysis, where we predict the deflection of > flexible wings under aerodynamic load (see 787) and actually apply the > deflection via Blender. However, the splines available in the lattice > deformer are inadequate as coded for our use, so I added a new spline...the > Catmull-Rom spline..which is the same as what Blender uses for animation. > this does not remove or alter an > y previous features, it simply adds a another option. > > To whom should I speak about patch files? Thanks. > > > _____ > David > > > > > On May 1, 2013, at 3:12 PM, dl...@me.com wrote: > > > Hi all. I discussed updating the lattice spline a few months ago. I > have since done some more research and would like to propose a very simple > improvement to the lattice deformer. The current options are "Linear", > "Cardinal", and "Bspline". The Cardinal spline is set to a tension of 0.71 > which can produce very wavy results when the lattice is dense. However, if > we changed the tension to 0.5, the spline becomes the popular Catmull-Rom > spline and produces very nice results, results we can use here at NASA Ames > to deform wings. The Catmull-Rom spline is already being used in other > parts of Blender, so it's natural to include it as an option in the lattice. > > > > The changes to the code are extremely minor...3-4 source files. 1-2 > lines in most cases, and only 12 or so more in one file with code that > looks very similar to what is already there. I can put together the patch > in about an hour. > > > > My proposal is this: > > > > Add "Catmull-Rom" as an option for the spline interpolators in the > lattice deformer. > > > > > > That's it. Quick and simple. Doesn't alter any current functionality, > it simply expands the current number of options from 3 to 4. > > > > Can such a project be approved? Thanks. > > > > > > > > _____ > > David > > > > > > > > > > On Feb 12, 2013, at 3:11 AM, Ton Roosendaal <t...@blender.org> wrote: > > > >> Hi, > >> > >> This code and the formula is like 18 years old, i'd welcome someone > checking on improvements. Rather to make it really good, not just with a > button to set the interplation value. > >> > >> Your 'plot' didnt get through... > >> > >> -Ton- > >> > >> ------------------------------------------------------------------------ > >> Ton Roosendaal Blender Foundation t...@blender.org www.blender.org > >> Blender Institute Entrepotdok 57A 1018AD Amsterdam The Netherlands > >> > >> On 11 Feb, 2013, at 23:26, dl...@mac.com wrote: > >> > >>> Pardon me if this is the wrong list to send this to. If so, I would > appreciate someone pointing me in the right direction. Thanks! > >>> > >>> > >>> The Cardinal spline interpolation for lattices befuddles me. The > tension-like variable (fc in the code) is set to 0.71, which I'm guessing > is approximately 1/sqrt(2). However, this gives very ugly and wavy results > on long straight objects like an airplane wing. In fact, the slopes at the > knots is just plain wrong. However, when fc = 0.5, I get very nice > cubic-spline-like behavior except at the end points where the code logic > just seems to be wrong. Nevertheless, the waviness at the knots is > disconcerting in the current distribution of Blender. The plots below show > what I mean. > >>> > >>> > >>> > >>> > >>> Thoughts? Any chance that fc (tension?) variable can be a parameter > the user could control? > >>> > >>> > >>> _____ > >>> David > >>> > >>> > >>> > >>> > >>> _______________________________________________ > >>> Bf-committers mailing list > >>> Bf-committers@blender.org > >>> http://lists.blender.org/mailman/listinfo/bf-committers > >> > >> _______________________________________________ > >> Bf-committers mailing list > >> Bf-committers@blender.org > >> http://lists.blender.org/mailman/listinfo/bf-committers > > > > _______________________________________________ > Bf-committers mailing list > Bf-committers@blender.org > http://lists.blender.org/mailman/listinfo/bf-committers > _______________________________________________ Bf-committers mailing list Bf-committers@blender.org http://lists.blender.org/mailman/listinfo/bf-committers