Hi, I sent this to Volker off-list already, but now that I can post, here it is for others to read: Volker, Thanks for the suggestions. The shared libtachyon via autotools is probably a good idea, though it would only be usable for the non-MPI builds. MPI programs must always be compiled from source unless one uses something like "MorphMPI" that simulates an ABI to abstract the native implementation. I will see about doing this later this spring after I'm done with the rest of the heavy lifting I'm doing getting the new version of Tachyon ready and releasing it concurrently with the new version of VMD...
Rendering to a memory buffer is trivial, and no, you don't need any OpenGL headers or anything like that, the core Tachyon library is independent of the supplied standalone driver program and OpenGL demo programs in the "demosrc" directory. To render to a memory buffer you would want to use one of these two APIs: / ** * Request Tachyon to save the output image in the specified * memory buffer, in raw 24-bit, packed, pixel interleaved, unsigned char * RGB bytes. The caller is responsible for making sure that there * is enough space in the memory area for the entire image. */ void rt_rawimage_rgb24(SceneHandle, unsigned char *rawimage); / ** * Request Tachyon to save the output image in the specified * memory buffer, in raw 96-bit, packed, pixel interleaved, 32-bit float * RGB bytes. The caller is responsible for making sure that there * is enough space in the memory area for the entire image. */ void rt_rawimage_rgb96f(SceneHandle, float *rawimage); So, for a 24-bit RGB image, Tachyon expects you to send in a pointer to a packed 24-bit RGB image buffer. You'd allocate the buffer and pass it to Tachyon in a code sequence like this: rt_resolution(scene, width, height); unsigned char *rgb24 = (unsigned char*) malloc(width*height*3); rt_rawimage_rgb24(scene, rgb24); The aperture option/API is going to change, so I will probably not document it quite yet, but if you want to fool around with that I would be happy to help you play with the existing code until I'm happy with how it works. I am in the process of massively updating the Tachyon docs and header files to make this all easier to follow. If you want, I can send you and any other interested parties a current snapshot for you to play with. Cheers, John Stone john.st...@gmail.com On Feb 6, 1:38 am, Volker Braun <vbraun.n...@gmail.com> wrote: > Dear John & sage-devel, > > I looked into libtachyon on Sage a while ago. Right now, we don't > build the library because tachyon already isn't that easy to build > without manual intervention. Sage only drives tachyon through > temporary files at the moment. Clearly, that is not ideal. My wishlist > would be > > 1) Use autotools/libtools to build a shared libtachyon in a portable manner. > > 2) I know that there is a way to render into a memory buffer, but I > haven't understood it 100%. I'm not sure if building it currently > needs OpenGL headers; If possible, we would like to avoid that > dependency. > > 3) Documentation would be nice ;-) For example we haven't quite been > able to figure out the aperture option, > seehttp://trac.sagemath.org/sage_trac/ticket/9855 > > Best wishes, > Volker -- To post to this group, send an email to sage-devel@googlegroups.com To unsubscribe from this group, send an email to sage-devel+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
