Theo Verelst Local Diary Page 59


I've ditched the usual header for the moment, I think it doesn't help much anyhow.
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  Sat Nov 29 15:04, 2008

Graphics! I could rent the Pixar Bluray with most of their public short movies and of course watched the films and the story of Pixar a number of times, also with different settings and on the (720) beamer, which was great.






The spacecraft imported from a internet souce in blender (latest version) with the latest blender to gelato python script from the NVidia forum. On the bottom the export scripts' buttons.
After using Render, an exported set of .pyg (the example script files of NVidia are call run.pyg which sounds funny) files results (of course the virtual camera has been adjusted, and I added several light sources) of which this is the main one. You'd need to have all the other files too, which is a bit much to put here (it would be quite possible on request): I'd like to stick with the idea I could put all web documents on the server on a Usb or other external sata flash (SSD) drive for future use, but by looking at the example (I had to work a bit to adapt it like I did) you might be able to do similar things (as I wrote, the model itself in 3ds form is on a web site, cudas to the person who made it!).

A rendering of the above, with no more than 3 light sources with no reflections or indirections or shadows (and no global illumination pass), so apart from the pro-accuracy (and adjustable high quality filtering) and the not to simple model (the fins on the side ar in the model, not textures) this is the simplest (=fast) rendering method with Gelato:



The following frame is the same spacecraft be shifted a little in a line which is probably 90 degrees straight ahead for the models intended fly method, and the frame is processed to test that out (in 16 bits High Dynamic Range per rgb component with cinepaint) (size is also 1920x1080 full HD):



Now I've made a motion blur of the movement between the previous frames (you could peek in the gelato model file how), computed in under 3 minutes on the quadro notebook (on Linux with gelato pro 2.2):



This is a downscaled rotation motion blur rendering (around the vertical axis):






And on rotating around the axis axis:



post processed (in 16 bits linear per RGB component) with Cinepaint:



different amount of translational motion blur:


The rendering of a sequence of 40 frames took place on the 3 GHz dual core pentium (D) machine with NVidia 6700 card and gelato pro on it, in this case on windows XP (Linux on the same machine also has Gelato Pro installed) from a Tcl scriptI made), both the CPU, the GPU and the Purevideo processor were working simuataneously for some hours on a row on the fairly heavy (albeit years old) machine.

   ani1.tcl         the animation script which uses the gelato files
   rename.tcl     rename ranges frames
   togif.tcl       convert 16 bit per comp. TIFF files to high Q Jpegs

In fact before I started the animation I had to figure out how to get Gelato graphics files to do transformations of the whole model (it turned out an additional Push/Pop transformation command pair can also change a absolute Transform command per object called from external files (a few dozen), and how to get the motion blur command set to work, in this case I used half a frame time shutter time with a 25 full frames per second frame rate. For the frames where th spacecraft gets close, maybe more interpolation frames could be utilized by gelato.

Since the machine was not exactly new or unused anymore, it has had the graphics card fan not working good at times, and when that happened the other day, lengthy rendering like below would risk get it hotter than 100 degrees Celcius, which may at some point break it, so below there is a temperature meter to make sure the fan works. Bit of a hassle to make that work at night, since I don't know wether the machine will halt when overheating threatens to take place.




The cpu use of the two cores is reasonable, but honestly when gelato is set to use both cores, it gets varying results, sometimes close to factor 2 speedup, sometimes only 60% total efficiency. The two cores make it possible to watch live sattelite TV on the machine at the same time as rendering, with a full HD screen, which is cool. Those 230 watts are at least good for something.



I used Cinelerra to process the resulting frames (infact I used a mpg2 movie I made from the frames in 99% quality Jpeg files which I made from 16 bits integer per component (HDR-RGB) TIFF files (no alpha). Cinelera processes it's intermedeate results in 32 bit floating point per component RGBA (!) but I in this case didn't feed it the original CG frames to just try it out quickly, it's about a second and a half which is processed in a number of seconds by Cinelerra.

The movie composed of the frames:

  tfjmovieq1.mpg        VBR q=1 mpg  the resulting sequence, playable by wmplayer with Purevideo hardware acceleration (2.2 Mega Byte)

The processed movie (straight from Cinelerra):

  tfjmovieq1p3.mp4    VBR q=1 mp4, the above but with 6 frames (unconditional) averaging (1.3 MB)






Stanford Trees

Dryads is scientific software which lets one generate a tree from parameters like branch number, branching amount, angles, colors, etc, which is fun, and it uses bigtime resources on a PC with graphics card:



There´s a web repository with the results from all users.

 I couldn´t resist trying out the savable .OBJ graphics file, loaded in blender, and did a tryout Gelato render:




not very great yet, pretty decent dual core use (it´s a 56 megabytes of gelato data) and a very interesting idea, maybe there are NURBS in the model, and maybe somewhere they got lost in the graphics chain, it would be nice to have beziers with nice lighting and (sub) surface properties in a powerful gelato render.