We had been using Blender for many of our projects before this point, and had quite successfully integrated it into our toolchain for solids rendering. Rendering fluids, however, posed a unique challenge where the surface geometry was extremely complex, time varying, and would have required topological remeshing every frame, risking the introduction of 'popping' artifacts. We had access to an older renderer which could directly render fluids stored as level sets and smoke volumes, via a ray casting algorithm.
However, it was slow not multithreaded! In my attempts to get the best of both worlds, I got in contact with Kevin Dietrich who had worked on integrating OpenVDB support into Blender for the purposes of rendering smoke and meshing particles. Using his changes as a foundation, I moved on to add support for rendering level sets as surfaces within Cycles, including shader support.
Toggle navigation Home. Blender with OpenVDB Integration This is work that I started in support of various research projects that my group at Wisconsin were performing with simulated fluids. The challenge was that we needed a modern rendering solution for fluid surfaces that could produce high quality results be easy to use run on Linux clusters directly ray-cast level sets We had been using Blender for many of our projects before this point, and had quite successfully integrated it into our toolchain for solids rendering.
These simulations were done with our group's own fluid simulation solver and then exported to OpenVDB for rendering within Blender.
For more information on the simulations and the solver used to produce them, please take a look at our Siggraph Asia publication on scalable Schur-complement fluids. Try downloading the video instead. This is a realistic style render, where the fluid is rendered with a clear glass surface shader and a volumetric absorption node for the blue tinting. Total render time was approximately CPU hours, with a frame count of frames.
The same simulation as above, only with a glossy shader colored according to the Z-height of the fluid to highlight detail. In this simulation, water is poured from above into a tray containing sixteen dragon sculptures. Total render time was approximately CPU hours, for a total frame count of frames. Here, smoke is injected into this model of the human bronchial tubes.
The render was produced as an emission render where the emission strength was controlled by an OpenVBD density field and the color was controlled by another OpenVDB field, this time encoding the vorticity of the smoke.
Total render time was approximately CPU hours, with a total frame count of frames. In this last example, thick smoke is injected through a series of angled tubes, creating turbulence.
The smoke is rendered using cycles scattering and absorption shaders, whose density and color is controlled, as in the previous example, by OpenVDB fields. The total render time was approximately CPU hours, with a total frame count of frames. The extreme expense of this render was in part due to trimming computations taken in the cycles shader to remove artifacts near the simulation boundaries, but the absorption and scattering shaders, along with data loading, were the primary culprit.
It was for this reason that true smoke rendering was performed for very few scenes in the paper, as we just couldn't afford the time requirements.
OpenVDB Remesh for Blender
Nathan Mitchell, Short description of error Houdini uses a newer version of openVDB 3. Here's the log:. I think it should simply ignore the version and not crash at least. Or you could add support for the newer version of openVDB, if you have resources, of course.
The OpenVDB cache expects a. Looking at your. It probably shouldn't crash just due to invalid. If you want to import the. You can ignore the message: "unsupported VDB file format expected version or earlier, got version ".
The volume still renders correctly. This is quite similar to what we have in blender. Can we just ignore the version and skip the metadata blender expecting? To fix this bug, we should add exception handling somewhere so we can report an error instead of crashing. Hm, like Geraldine Chua gschua said, blenders vdb import is not really meant to use vdbs generated in other software yet.
Whilst reading files written by other software should be possible, as long as the other software exports metadatas which would make sense in Blender, reading such files is not officially supported since that to properly support external.
Therefore I'm archiving this report. Metadata reading happens here and it seems blender is actually pretty dependent on it. Create Task. Edit Task Edit Related Tasks BF Blender Backlog. Brecht Van Lommel brecht. Geraldine Chua gschua.The Blender Foundation and online developer community are proud to present Blender 2. The 2. Improvements to snake-hook to drag out long extruded segments, and rotate the snake-hook brush using the new rake option.
Armatures: selection now supports selecting children, immediate children and siblings, added options to draw custom shape scale. New Add-on: Blend File Utils, supports packing blend files including all their libraries and dependencies into a self contained ZIP file. Compositing: new invert option to the 2D stabilization node, use mask name as mask node label, expose track velocity as an output of Track Position node, new option to extend image bounds when blurring.
As for every Blender release, hundreds of bugs were fixed, thanks to our hardworking Blender developers! The donation program to support maintaining and improving Blender, for everyone. Grease pencil stroke sculpting and improved workflow. Reworked library handling to manage missing and deleted datablocks. Redesigned progress bar. Edit mode boolean tool, better decimate modifier. Blender now requires OpenGL 2.
Download Latest Blender Download Blender 2. New in Blender 2. Customizable motion blur position, support for rolling shutter. Custom baking passes. Performance optimizations for large node shaders. Improved default settings. User Interface Progress bars got a complete design overhaul. Support for multi-line text in tooltips, render stamps, frame nodes and meta data display. Better anti-aliasing for OpenGL renders. And more! Modeling Decimate modifier is now symmetry aware.
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Blender Development Fund The donation program to support maintaining and improving Blender, for everyone. Follow Blender.One thing holding us back implementing blender fully aside from the particle system et al in our effect dept is the lack of openvdb importing and rendering.
Getting these imports is a major deal for FX - as an example, as it can be exported in multiple ways, a single use option may be problematic.
This is a major thing for everyone in FX and has been requested multiple times. Any chance it could be appended to the mantaflow builds? Speaking of mantaflow, while simulating we really need to see the update in the viewport. The beauty of the existing smoke sim is that you can play and see the update in real time in the viewport, which is a step up on a lot of smoke sims out there. Caching and playing back is a major step back as productivity really suffers.
The big sell I have with the FX team here is that you can see this stuff in real time and their layout and design is so much faster. Any chance we can just call the last frame and display that while the system is simming the next frame? Hello there. Brecht the lead developer of cycles wrote a proposal a bit more recently New object typesso I guess you should ask him directly maybe tag him here.
As an FX artist of x-years I was staring at the system and just banging my head on the desk trying to figure out how to get something renderable, even an animated object offset by time. Things like this will deter a lot of people without proper documentation. The primary problem is the lack of supporting files that people can deconstruct.
PS your non-native English is better than my native English. Still need the openvdb import Pete. This may be of interest for you an me in this case also. Cheers, Daniel. Will Mantaflow enable it at some point?
User Feedback. PeteDraper November 3,am 1. Thanks, Pete. BenjaminMuller November 2,pm 2. PeteDraper November 2,pm 3. BenjaminMuller November 2,pm 4.
PeteDraper November 2,pm 5. Pete PS your non-native English is better than my native English. PeteDraper November 3,pm 6. Mantaflow now apparently has feedback during sim. Retracting that wish.OpenVDB is a file format that allows us to import complicated simulations like explosions with ease.
It's supported now in an experimental build of Blender. This video shows how to get started with just a few clicks. Hi, my name is Jan and I help companies by creating short videos for their websites and internal use, mostly as a freelancer for agencies. I post daily one-minute tutorials for Blender users and wrote the popular "Blender Secrets" e-books.
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You can also subscribe without commenting. You're blocking ads, which pay for BlenderNation. Read about other ways to support us. Jan van den Hemel writes: OpenVDB is a file format that allows us to import complicated simulations like explosions with ease.
It only takes a minute to sign up. Will there be an option in Blender 2. OpenVDB loading in Blender is limited to smoke simulation caches. The system is not designed to load external files. There's probably some horrific way to format an VDB so that Blender is fooled into thinking it's a smoke cache, but I'm not aware of any working setup for that.
There is an eventual plan to add a volume object to Blender that would support loading arbitrary OpenVDB files, among other things. There is no timetable or version for this. In the meantime, in certain limited cases you may be able to get by via using Houdini's scatter SOP to fill the VDB with points, exporting these points to Alembic, then using Cycles' Point Density texture to render the point cloud.
It won't have the exact shape and is of limited functionality, but depending on your needs it may do the trick. Sign up to join this community. The best answers are voted up and rise to the top. Home Questions Tags Users Unanswered. Import OpenVDB files? Ask Question. Asked 1 year, 1 month ago.
Active 1 year, 1 month ago. Viewed 3k times. Active Oldest Votes. JtheNinja JtheNinja 8, 1 1 gold badge 23 23 silver badges 40 40 bronze badges. Sign up or log in Sign up using Google. Sign up using Facebook. Sign up using Email and Password.GitHub is home to over 40 million developers working together to host and review code, manage projects, and build software together. Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.
Already on GitHub? Sign in to your account. I am working on a production that calls for volumetric data being created from Houdini Indie and I would like to use Blender for look development and RIB authoring to send out to my render farm. I am more than happy to do what I can to help test this feature, though I am not a developer myself. Btw you can use the openvdb cache that blender creates itself but of course Houdini is better for sim.
On Wed, Nov 16, at PM shawn-kearney notifications github. This should be fairly easy actually.
REC-Live 11 - MANTAFLOW is BACK and OpenVDB awesomeness!
How would you like to specify the channels in the vdb file so you can use them in your shader? It may be possible to read them in Within Object Attributes you would select the sequence and then you would type in the grid you want to render into PrimVar.
That's kind of how we're used to doing it. I suppose you could make an OpenVDB node that would open a VDB sequence and allow you to select the grid from a list and will set the Primitive Variable from that selection. I guess at that point you'd apply the volume shader to arbitrary geometry to serve as bounds? I'd prefer this myself, however If the PrimVar node had an input, you could load in the VDB sequence in a similar way as an image texture, and if you wanted a drop-down menu on the PrimVar you could have it detect the presence of an input and change the string input to a selection based on the input.
PrimVar though should still be allowed to function as it is currently when a node isn't attached. This would be pretty slick, and may have other uses as well, though i am not sure if Primitive Variables work this way or not and in Maya and Houdini I don't think PrimVar has any inputs, so even if it were possible, this would represent a paradigm change in how the node operates.
Because the density value is float it would seem we could combine VDBs together using arithmetic into the same shader. This could be extremely useful. Sorry I should have been more clear. The way I was thinking of doing this was similar to where in the object attributes now you can select to use a rib archive rather than the geo data for an object.
That's all super simple, and I could have that working in a matter of minutes. However, the channel names in the VDB are the issue. RenderMan needs to know what names, 'density', 'fuel', 'temperature' to pull from the VDB file. We could. The simulation fields can be found in the. The presence of a given field depends on the simulation settings, e.
Yes those are for the blender ones According to that there's only five data grids that can be exported: Density, Heat, Fuel, Velocity and Temperature unless I'm reading that wrong.