The VFX here consists of particle simulation for the initial magical pollination seeds.
Then I added a vine simulation for the grown of the plants.
MA_VFX 23/24 Beacher
22048303
What VFX is in this shot?
Firstly, there is a ground deformation relative to the impact site of the rocket.
Then, there is the debris at the impact site.
Lastly, there is a smoke simulation.
No problems just normal workflow
RnD
Applications of Houdini for Cinematic Scientific Visualisations
Abstract
SideFX’s Houdini is a software used mainly by artists in the visual effects (VFX) industry, it has been picked up by many scientists for creating visualisations for scientific communication and educational purposes. This form of visualisation is also known as cinematic scientific visualisation. This essay discusses and outlines some of the primary reasons for the extensive use of Houdini in academia. Three main reasons are highlighted for the reason why Houdini’s use is justified for cinematic scientific visualisation: (i) Houdini is a node-based software package where it promotes a non-destructive workflow for users. (ii) Data-driven software means it can handle large datasets, which is often the case for scientific data. (iii) Lighting, camera and rendering features that traditional scientific visualization tools lack. The essay also notes some of the potential drawbacks of current definitions of Houdini in scientific visualisation.
Research question
Critically evaluating the applications of Houdini outside of Film/TV, especially in the field of scientific visualisation.
Keywords
Cinematic Scientific Visualisation, Data Visualisation, Simulation
Introduction
This essay attempts to postulate that Houdini holds a significant role for cinematic scientific visualisation. As there are different definitions for visualisations in the science community, this essay will only focus on the role of Houdini in the field of cinematic scientific visualisation. This essay highlights three justifications where Houdini shows promising viability in communicating research analysis. Even though, Houdini excels at visual effects, it is noted that there are still some challenges for Houdini to be fully adapted into the production process of creating cinematic scientific visualisations
SideFx Houdini Software
Houdini was developed by SideFx and it is well known for its capabilities in high-end visual effects. In the film, gaming and advertising industry, it is one of the most extensively used computer graphics software. Due to the continued development by SideFx, Houdini excels at simulating rigid bodies, fluid dynamics and particle systems (Aguilera and Johansson, 2019).
Another feature of Houdini that sets it apart from other 3D computer graphics software is its node-based workflow. This workflow facilitates flexibility and efficiency in altering geometries and simulations. This flexibility allows for the creation of custom tools or node networks which can be easily redeployed to different scenarios without the need for building the setup from scratch.
Literature Review
Scientific visualization, also known as data visualization, involves the use of graphical techniques to present scientific data in a way that enhances comprehension, interpretation, and insight. It is widely used in various scientific domains such as astrophysics (Burkhart et al., 2020), biology (Sener et al., 2021) and remote sensing (Wróżyński, Pyszny and Wróżyńska, 2024). However, it is important to distinguish between scientific visualisation and cinematic scientific visualisation. As visualisation caters to different groups of audiences, the former generally refers to graphics presented to other fellow academics. Traditional science visualisation is usually done with science visualisation tools such as VMD which cantered around accurately visualizing molecular data for scientific purposes, with a focus on clarity, real-time performance, and scientific accuracy (Humphrey, Dalke and Schulten, 1996). Cinematic scientific visualisation’s target audience is commonly made for the general public with no prior background knowledge of the data presented to them (Borkiewicz, 2020, 1:24). Hence traditional scientific visualisation might not be suitable to effectively communicate the information to its audience.
The role of Houdini is crucial in cinematic scientific visualisation as part of the pipeline for producing content for science communication. (Sener et al., no date) stated that Houdini has become the main software application that helps to drive the production process for their film Birth of Planet Earth. Besides the field of astrophysics, Houdini is also often employed in the nature sciences. In Harrap et al. (2019) research, the estimated rockfall path is simulated on Houdini with the use of the Rigid Body Dynamics (RDB) simulation tools.
From the few of the aforementioned examples, it is hence important to understand the importance of Houdini and discover what other features which Houdini might lack which could possibly pose challenges for cinematic scientific visualisation.
Complex Lighting and Rendering Features
As Houdini’s main target audience is for VFX artists to create photorealistic content, its lighting and rendering focus on high-fidelity outputs. Lighting system inside Houdini allows the user to have much freedom and flexibility to art-direct the scene. For example, many different light types are included in the software and lighting properties can be adjusted to a large extent to achieve the required look (Borkiewicz, Naiman and Lai, 2019). Besides lighting, Houdini also supports high-end render engines like Karma or third-party renderers like Redshift or Octane. Overall, the workflow of lighting, shading, rendering and post-production produces high quality realistic imagery. With the use of datasets from scientific research, visuals can be improved with Houdini following a similar pipeline.
Specialised Simulation Tools
Apart from lighting and rendering, simulation tools in Houdini works very well for visualisation as well. As scientific simulations often deal with phenomena similar to visual effects in the movies. Houdini’s simulation features are adept at handling the complexities required by academics. For instance, Houdini contains fluid simulation solvers using the Fluid-Implicit-Particles (FLIP) method to model the behaviour of liquids with high precision (SideFX, no date). It is able to capture the nuances of fluids such as ripples and viscosity variations. For example, researchers are able to utilise Houdini to calculate and model ship’s motions based on the ship wake patterns simulated with Houdini (Ahmadibebi, Jones and Shirkhodaie, 2022). Furthermore, the non-destructive workflow in Houdini allows researchers to easily build visualisation variations by adjusting and fine-tuning the initial starting conditions. These unique features of Houdini are crucial for scientists to iterate more efficiently and produce quality results to be communicated to their respective audiences.
Handling Large Datasets
Data handling is another area in which Houdini excels for cinematic scientific visualisation. Houdini is able to efficiently manage complex and large data sets with ease. Furthermore, the software supports various different data formats. It can handle simulations with point counts in the millions and billions (Agrotis, 2016). Houdini also allows for customisation through the use of scripting and programming plugins to interface with existing other tools and libraries for better connectivity within a larger scientific data ecosystem. For instance, Borkiewicz et al. (2018)’s work contains custom C++ plugins for Houdini for their cinematic scientific visualisation work. Hence, these capabilities make Houdini an invaluable tool for managing, analysing, and visualizing scientific data.
Drawbacks and Challenges
Floating Point Precision
Although Houdini is suitable for cinematic scientific visualisation, there are still some drawbacks of the software to be considered. Houdini operates with 64-bit floating-point precision to handle calculations and simulations in conventional Cartesian space. Floating-point arithmetic introduces rounding errors due to the finite precision of floating-point numbers up to 64 decimal places. The implication of float point clamping in Houdini will ultimately cause inaccuracies in simulations. In the field of astrophysics, where simulation involves values both very large and very small, rounding errors can accumulate temporally leading to drastically different results (Izquierdo and Polhill, 2006). The resulting simulations will diverge from the expected behaviour or sometimes cause visual artefacts that significantly impacts the visual quality of the visualisation.
Non-Uniform Data Resolution
Another caveat would be the incompatibility of cross-software data resolutions. For instance, meteorological spatial data is often recorded in non-uniform resolution. This could be the case where only the significant areas are given priority in terms of resolution while lowering the level of detail (LOD) in arbitrary areas (Roesler et al., 2020). Volume data from such cases would not produce good results in Houdini as volume grids in Houdini expect voxels to be uniform. Even solutions to overcome such challenges can be problematic as secondary complications can arise. For example, matching the resolution to the finest data resolution comes with a high cost of resources needed to effectively simulate and render the data. Taking mean data resolution throughout the dataset can help reduce the computational cost but at the expense of inaccuracies from data loss.
Conclusion
In summary, this essay has covered briefly why it is at the forefront of the visual effects industry and is also growing in popularity as a visualisation tool for the scientific community. Three main reasons are also discussed as to why Houdini is feasible for scientific visualisation. Lastly, the essay cautions against some of the potential drawbacks of Houdini for scientific visualisation as it is still lacking in certain features. After all, each software has its pros and cons. It is important then for the user to balance between clarity vis-à-vis accuracy.
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Categories
Term 1 Final Video Assignment
Ideation
#1 Space Battle
The scene shows beauty shots of large spaceships to introduce scale. Then it shows the deployment of smaller fighter ships going to battle formation. All of these build up to the climax where enemy ships jump in from hyperspace and start to attack and deploy their own ships. This leads up to the high point of tension where we cut because there is no time and budget to do the actual space battle.
#2 Perfume Advertisement
This idea was to try out motion design coupled with VFX. I wanted to try this because I feel like given the time frame of the assignment it would be interesting to explore. Since the intensity will increase as we progress. It is better to do something more ambitious and make mistakes early on.
So the idea was to create an abstract and moody commercial that showcases a uniquely designed perfume bottle.
#3 Chocolate Ice-cream Commercial
#4 Car Commercial
Conclusion
In the end, I went with #2.
Mood board & References
FX References
Lighting Mood board
Mood Reel
Storyboard
3D Model
Look Dev Materials
Styleframes
Animations
Animation is not my strong suit, I need more practice. But I tried my best to follow the mood reel’s animation. However, I feel that overall the animation is the biggest problem in this project.
Especially the cut after the bottle’s emergence is very glaring. If there is more time, I would need to rethink how to better transit. Though I could simply merge those two shots into one continuous shot. However, due to the lack of time, I just did a cut as they are simulated separately.
Overall, the pacing is a little fast for my liking, I feel like a lot of the shots can be dragged out. That being said, I do like the last transition from the close-up to the end scene. That one feels smoother and I am happy with it.
FX
For FX, this is the part I love the most and want to improve. It consists of mainly two simulations; (1) Rigid Body Dynamics and (2) Pyro (Smoke).
Having an art-directed fracture is the foundation for both simulations. I employed both procedural and manual boolean slicers to get a fracture that I was satisfied with. In addition, I added interior details in between the fractures.
The smoke simulation is pretty straightforward once the RBD is complete. I just take the pieces where I want smoke to spawn and use them as emitters for my smoke and simply run a smoke sim. viola. The combined FX is shown below.
Compositing
Compositing is pretty straightforward as well. For me, I like to make my raw render look as good as possible so that I would not have to spend too much time on compositing (a little bit unorthodox I know).
However, sometimes there will still be times when the deadline is very close (like this time) and there isn’t time to rerender. Hence, I always like to output as much information in my render through AOVs so that I have the option to do editing in post-production. (image above).
Also when doing AOV channels, I like to output my light AOVs as well. Having light groups in my render would mean I can adjust my lighting without returning to 3D.
For post-production, I just try to ensure that all my scene colour is consistent. Then I applied an overall colour grade and added some grains.
Sound Design (SFX)
Final Output
Combining everything together after weeks of work, here it is! The final product. Please on sound as there is audio to it as well! Thanks for staying with me until this point. Enjoy
Reflections
Overall this project was a successful one. I learned a lot about the project pipeline. I also realised my weaknesses and strengths. I feel that I would need to improve my animation skills and camera animation. Right now, it is a bit stiff and not dynamic enough. For future projects, I want to try doing another aspect of houdini.
You have a well-presented and thorough blog. It is easy to navigate and see how you plan your documentation even in the areas that are missing. The information so far is good but mostly focused on the technical part. It will be good to see your thinking and reflection for every part of the process. Also try to finish the missing areas for the summative submission, especially the weekly tasks that were given in the class.
For the final project you have shown a good number of experiments regarding the design, environment and animation (motion graphics) but you haven’t included most of them in your blog.
Do not forget to make a VFX breakdown video for the summative submission.
-Manos
From the feedback, I realise I need to be more proactive at uploading my progress. Also, I need to at more of my personal thoughts and reflection from the things learnt in class to the blog posts.
Brief
As part of the term 1 VFX fundamental course, we are instructed to construct an environment scene in UE5. The theme is cabin in the woods. The process for this assignment would be:
- Look for references
- Block out the scene
- Add materials and look dev
- Import models
- Scatter vegetation(tress and plants)
- Setting cinematic cameras
- Additional elements
- Render image sequences
References
I went online to look for some references to give context what a cabin in the woods would look like. I plan to add an additional element of water in my scene. I imagine my cabin would be positioned beside a body of water such as a lake.
Blocking
I moved on to blocking out my scene. The concept would be to have mountains/hills as the background. The cabin itself would be by a pond and surrounded by trees. The big cubes represent the mountain, the cylinders are trees( the quantity is TBD). The white plane is the pond/lake and the small box will be the cabin.
Look Dev/Materials
I tested the animated water surface material. For the lake surface, it would be darker and slightly green beside on references.
Importing 3D assets
Next would be importing the 3d models of the cabin together with the textures.
Vegetation
Afterwards, I proceed with the scattering of trees. Both the water plants and trees are hand painted in the scene using foilages in UE5.
Adding Camera
After completing the scene, the next step would be to frame my camera angles. I tested some angles which I find aesthetically pleasing.
Additional Elements
Lastly, I added two additional 2 elements in my scene to make it more interesting.
Final Result
Reflection
Overall, this is a short and fun project to do. Quixel bridge definitely made the whole process a lot faster as very little modelling is needed for this project. UE5’s real time render is really fast and realistic(ish). The most challenging part would working with the shadows and the lighting. I wasn’t pleased with the initial render and had to color correct in the post using Nuke.
Idea & References
Assets
FX
Rotoscope
Composite
Final Video Assignment
Reflection
Need to review one’s work before publishing it. No matter the amount of pressure or little time.
Reduce the reliability of the artist.
Stages in Production for Film in Compositing
Temps/Postviz
Trailers
Finals
QC
Software Project Management
Google Docs and Sheets
Ftrack
Shotgun/Shotgrid
Production Roles
Line Producer
Central to VFX project management. Liaise with all aspects of production and post-production.
VFX producer
Ensure the studio completes projects on time and to a high standard.
VFX Dailies
A daily meeting in the morning when artists working on a project meet to share their work in its current state. Ensure that you are moving in the right direction and getting feedback.
Get your current versioned work uploaded.
Tech Check before publishing
Check if you did all the notes for the shot
Compare this version with the old one
Check editorial
any retime in the shot
your shot has the latest CG and FX
Your shot has the latest camera match move
Write in the comments if you have any personal notes
Do you have different alternatives for the shot
QC
Desk Dailies Review (small)
1 VFX sup, 1 VFX Prod, 1 Line Prod, 1 Lead Comp
+ artist (you)
Slack, Zoom, Teams for remote
Small Cinema Dailies (medium)
1 VFX sup, 1 line Prod, 1 VFX Prod, 1 Lead CG, 1 Lead comp
+ tech team + artist/s(your team)
Big Cinema Dailies (big)
VFX sup, line Prod, VFX Prod, Lead CG, Lead Comp – studio team
VFX sup, Director, Producer, Editorial, Lighting lead – client team
Reflections
On-site offers more learning experience than remote/online.
Trust is important.
Word gets out fast so don’t be “that” guy/girl.