this is a friend of Farsthary: many of you are waiting eagerly for a real working build on their platfrom, and as Farsthary can not get connected the week-end…

Our super cool Matt Ebb reviewed and included 2 days ago Farsthary’s voxeldata and ERT

So just compile and run the last sim_physics revision. Here are the current builds (thank you graphicall people! :):

* MacOSX 10.5 Intel: build + simulator (thank you Jens!)

* Windows:  build + simulator (thank you Afalldorf!)

The ERT slider was renamed “Depth Cutoff” (1=max speed-up for dense material but some accuracy loss)

Here is a blend with the right settings for voxeldata rendering:

just launch it (naturally after loading the “smoke.bin” in the texture panel (F6 touch)) and observe/tweak the settings…

(for best quality, decrease the “step size” at the top of the “Volume” panel)

Keep in mind that:

– The resolution setting in the simulator is just the dimension of the core: you have to add the boundaries (1 cell width at  each side, contain the initial speeds) so if the resolution is 62 (standard one), the resolution for voxeldata (“smoke.bin”) in blender texture panel is 64…

– the voxeldata currently requires an external texturing reference: just put an empty object inside the cube, go the “Map Input” panel, click “object” and enter the name of the empty..

– the ascending axe for the smoke (convection) is currently the -y one of the empty, and the empty size is the one ot the voxel data: if you want that all the smoke fills the cube, just make the empty axes as big as the latter one. (just look at the blend for the right position of the empty, which must be in an appropriate corner for complete filling)

– here are default settings for smoke simulation (resol=62 by default):

* beware about the frame number: about 1 Mb per frame

* time step resolution: 0.1

* diffusion factor: 0 (increases the speed of dilution of the smoke)

* viscosity: 0 (increase the resistence of smoke to change its moving state, inercy)

* buoyancy: 10 (increases the ascending acceleration of the smoke: hot gases are less dense and so quickly go up)

* vorticity confinement factor: 1 (increase the turbulence)

* vorticity confinement amplification factor: 0 (is a recursion factor for turbulence)

* temperature simulation: no (additional bin file for voxeldata with these values)

* …..: no if you only want one density voxel texture..



16 thoughts on “Concretely?

  1. David says:

    When I try to compile the latest sim_physics branch (rev 17828) on MSVC 2008 on windows I get the following errors;
    —— Build started: Project: BRE_render, Configuration: Blender Release Win32 ——
    ..\..\..\source\blender\render\intern\source\voxeldata.c(47) : error C2054: expected ‘(‘ to follow ‘inline’
    ..\..\..\source\blender\render\intern\source\voxeldata.c(48) : error C2085: ‘_i’ : not in formal parameter list
    ..\..\..\source\blender\render\intern\source\voxeldata.c(48) : error C2143: syntax error : missing ‘;’ before ‘{‘
    ..\..\..\source\blender\render\intern\source\voxeldata.c(79) : error C2054: expected ‘(‘ to follow ‘inline’
    ..\..\..\source\blender\render\intern\source\voxeldata.c(79) : error C2085: ‘lerp’ : not in formal parameter list
    ..\..\..\source\blender\render\intern\source\voxeldata.c(79) : error C2143: syntax error : missing ‘;’ before ‘{‘
    Build log was saved at “file://c:\build\build\msvc_9\source\blender\render\BuildLog.htm”
    BRE_render – 6 error(s), 0 warning(s)



  2. David says:

    I think I got it to work! 🙂 I had to change a few things in the voxeldata.c file to get it to work. Here is a list of the changes;
    line 47; changed “inline” to “_inline”
    line 79; changed “inline” to “_inline”
    Not sure if this causes any problems but everything seems to be just fine. I will do some more testing and then up load a windows build ASAP.
    BTW that “_i” in my previous comment (error C2085) should be “_I”.


  3. David says:

    THANKS! I just updated the build with your fix.
    I was trying to up load a build to but I keep getting errors. Apparently my internet is too slow or something. 😦 I tried 3 times @ one hour each time! I will up load as soon as I get a chance to use high speed internet.


  4. jens says:

    Hi farsthary, i had a bit muddle with doubleposting at GRAFICALL, the
    correct link to sim_physics is :

    and original Volumetrics#2-build is:


  5. Ruddy says:

    Hi Dennis:
    1) download the simulator, the build and the test file.
    2) free some place on your harddrive: if you want a 10s smoke (250 frames at 25 fps) , it uses 250 Mb….
    3) launch the simulator and answer the questions following the advices of the post
    –> it creates a huge “smoke.bin” file after a dozen of minutes (on my pentium 1.7 GHz) in the same folder than the simulator
    4) launch the build, open “test.blend”, then the texture of the cube (F6 when the cube is selected) and click on the path name to select the one of your smoke.bin
    5) render as usually. Modify the cube AND the empty similarly if you want to change the smoke position
    feel free to ask questions


  6. Max says:

    Awesome work guys!!!
    I can’t thank you enough for those addition.

    Can you host the .blend elsewhere please,
    like mediafire
    I can’t open it from here.
    thank you!!!

    sorry for my english i’m french canadian 🙂


  7. Ben says:

    Hi there,

    Myself and others it would seem from the comments have had issues rendering voxel data from the windows build. The build renders volumetric materials, the generator seems to generate the Smoke.bin file ok from what I can tell, but the build crashes when the render button is hit. Tried using the suggested settings for the smoke and the pre-made .blend file and still nothing.

    Any advice on what to look for?

    Once again, thanks for the hard work and all the best with your thesis!


  8. James says:

    I’m having the same issue Ben is having.

    I’ve followed the documentation, used the ready made blend file, and as soon as the render window pops up blender crashes, as if its choking on the smoke.bin file somehow


  9. Sjoerd says:

    I also get a crash when I render it. And is this going to be intrgrated in a new version of blender? Can you make it much simpeler then?


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s