For his graduation work, Niels Timmerman took on the task of researching realistic behaviour and influences of water on a moving character. The goal was to make a small-scale, close-up VFX shot with a character, which moves in water that behaves naturally.
This is how he did it:
Plan of Action: Going through the complete VFX pipeline
The first step was to search for something to work towards. Good reference materials are vital. Finding references of what the finished shot could look like, what type of face you want to make, what kind of hair you would like to put on the character, what water itself looks like, detail shots of skin, wet skin, etc.
After finding enough reference materials, you can start searching for the right software to use. My main software for sculpting has always been Zbrush. For rendering I use Vray for Maya. My personal preference is to use Maya 'out of the box' for most of my solutions. I think this is a good way of dealing with 3D problems since the software is available for everyone, and as a student this is especially handy since no extra costs are needed when using this approach. However it is good to at least try out some other software for possible better results. Liquid solutions, for example, might need some more advanced programs like Realflow to get the desired results. After that, I started gathering information about software or certain techniques used to make all the parts. Information about liquid simulations, skin rendering, water materials, detail sculpting techniques, bifrost workflows…
By using small scale environments it’s possible to test simulations quickly. A simple ball can be used to test the simulated water's behaviour. A combination of tweaking and searching for settings can lead to preliminary test results, on which you can base your ultimate settings. A base mesh of a sculpt can be used to quickly try out more detailed sculpting techniques, bake the normal maps on and render it in Vray. This is also where I practised skin-rendering shaders. There’s a lot of information about creating hair in Maya. I put hair on a sphere for quick tests of dynamics simulations and rendering. The sphere was then replaced by a hyper-realistic face. This was done by sculpting it in Zbrush. To be able to animate the face, even a little bit, you also need to make blendshapes.
After all of the testing you can start making a bigger simulation of the water you need for the scene. This will take a lot of computer power.
When all the parts (or test parts) are made, you can start tweaking materials for rendering. Play with the lighting and the settings for better results. As always trial and error is the way to do it. Try to streamline your workflow using low render settings and small scale environments or partial rendering, starting from presets, learning enough about the underlying theory behind everything.
In the end all renders need to be composited into the final shot. Smart use of different render passes can provide useful compositing techniques. Here you can see the result after compositing all of the parts together.
First of all you need decent hardware if you want to make serious simulations. A laptop might be a bit slow. For testing purposes it can be used, but even then a lot of crashes occur and it will take a long time. When you have to render out the whole animation with water and hair and all the other components, a laptop will certainly not suffice.
Overall there was a lack of documentation about many techniques I needed for this project. I haven’t found good up-to-date Vray Skin material tutorials, for example. Wet characters in general is a topic not often discussed. I had to figure a lot of stuff out on my own. However this is a lot of fun and rewarding after a couple of somewhat successful results.
This project needs Realflow for the best results. Since Bifrost doesn’t allow for enough control over small scale stickiness between the skin and the water. Bifrost is not very good for small scale projects. Realflow does all of this very well but the problem is the price. Another problem is that I haven’t been able to export an animation from Maya to Realflow. SD exporting results in crashes in both Maya and Realflow.
By then applying everything I learned during the research I also learned a lot.
I went through the entire process of making a VFX clip: concepting, directing, modelling, sculpting, simulating, animating, texturing, rendering, compositing, editing, sound editing,… All of this has made me realise how important it would be for a team of multiple people to communicate about everything. It also taught me a lot about every stage of the process, and what to take into consideration when communicating with colleagues responsible for different aspects. I know how to estimate the time needed to complete certain tasks and I know what’s possible. This makes me much more valuable as a VFX artist.