Thanks to everyone for the excellent feedback. Thanks, Jonathan for the details on nurbs. I definitely don't want to step on any toes. I was just looking for a way to get started and thanks for the green light!
Regards, ...John On Wed, Jul 2, 2014 at 11:39 AM, Jonathan deWerd <[email protected]> wrote: > >> So, I'm wondering how others have learned the code, or is it just a > matter > >> of putting in lots of time? > > It's just a matter of putting in lots of time. Not what you wanted to hear > but I think you suspected it was true already. > > I'm the summer student working on NURBS. Just wanted to drop by and say > that you could work on this bug without stepping on my toes. The NURBS > extrusion operator already exists, ctrl+click just doesn't call it. If you > stick to calling the extrusion operator you will guarantee compatibility > with any changes that I make since I have to make the extrusion operator > work regardless. > > In order to decide which edge to extrude from, you will need to access the > NURBS object (search for "typedef struct Nurb"). Relevant fields are: > > Nurb nb; > nb->pntsu; //Number of control points in u direction > nb->pntsv; //Number of control points in v direction > nb->bp; //A 1D array of BPoints that holds the 2D array of control points. > // Writing coords (u,v), they are packed like > // > (0,0),(1,0),...,(nb->pntsu-1,0),(0,1),(1,1),...(nb->pntsu-1,1),...,(nb->pntsu-1,nb->pntsv-1). > > BPoint p; > p->vec[0]; // x > p->vec[1]; // y > p->vec[2]; // z > p->vec[3]; // w > // NOTE: this BPoint corresponds to the point (x, y, z) in space, *not* > (x/w, y/w, z/w) as per mathematical convention for homogeneous coordinates. > > Hope that helps. Nurb::bp packing order and BPoint's strange > half-homogeneous behavior were discovered by trial+error+debugger. I > haven't written any interactive operators yet so I can't help you there. I > don't think you would be shooting yourself in the foot by working with the > NURBS code. It's old but it seems to use the same operator and undo code as > the rest of blender. It's also relatively monolithic compared to BMesh: it > doesn't change representations in editmode, it doesn't keep its own > separate stack of operators, it doesn't have a domain-specific language to > represent modifications (why does BMesh even have that anyway?), and the > relevant struct definitions fit handily on half of a single screen. > > Cheers, > Jon > > > On Jul 2, 2014, at 11:50 AM, Howard Trickey <[email protected]> > wrote: > > > Some introductory FAQ material is here: > > http://wiki.blender.org/index.php/Dev:Doc/FAQ#Source_Code_FAQ > > > > As it says there, reading all of the docs on > > http://wiki.blender.org/index.php/Dev:Source/Architecture > > is useful, though hard-going and somewhat out of date. > > > > It's probably best to start on just a small area of the code and not > worry > > about the rest. > > Follow through what happens when you execute some command in an area that > > you are interested in. > > Do what you are trying to do: fix a small problem or make a small feature > > change in that command. > > Probably doing a NURBS task isn't the best idea to start, since there is > a > > summer student right now working on revamping NURBS, and anyway that code > > is fairly old and somewhat removed from the modern part of Blender. > > > > - Howard > > > > > > On Wed, Jul 2, 2014 at 11:07 AM, John Alway <[email protected]> wrote: > > > >> Hello, > >> > >> I've been working to understand Blender code so that I can try my hand > at > >> fixing some bugs and adding some features as needed. However, I'm > finding > >> the learning curve to be quite steep. C and C++ code per se are no > >> problem for me, but it's hard to determine what the code is doing, > because > >> there are many abstract concepts that have been implemented. > >> > >> I was trying my hand at Issue T39656, just to see what it would take: > >> https://developer.blender.org/T39656 > >> > >> And, to help me along, I've been using the Visual Studio debugger and > I've > >> read many things out of the wiki, including this overview: > >> > >> http://wiki.blender.org/index.php/Dev:Source/Architecture/Overview > >> > >> However, at the end of the day, this is proving to be pretty heavy > going. > >> > >> So, I'm wondering how others have learned the code, or is it just a > matter > >> of putting in lots of time? > >> > >> I do know OpenGL and I have studied many graphical concepts, and I've > done > >> a lot of matrix math for rotating and translating objects, etc. But, > I'm > >> sure there is much to more learn, anyway. There always is! > >> > >> Anyway, I'm just looking for pointers and any kind of help on this. > >> > >> Thanks for any feedback! > >> ...Regards, > >> John > >> _______________________________________________ > >> Bf-committers mailing list > >> [email protected] > >> http://lists.blender.org/mailman/listinfo/bf-committers > >> > > _______________________________________________ > > Bf-committers mailing list > > [email protected] > > http://lists.blender.org/mailman/listinfo/bf-committers > > _______________________________________________ > Bf-committers mailing list > [email protected] > http://lists.blender.org/mailman/listinfo/bf-committers > _______________________________________________ Bf-committers mailing list [email protected] http://lists.blender.org/mailman/listinfo/bf-committers
