Harnessing the wind: A Technical Dive into Kim Byeong Jin's VFX Craft
Kim Byeong Jin, inspired by a challenge from the Korean Game VFX Artist Community, starts with a blank canvas. The theme? Wind. What unfolds next is a fascinating journey from rough sketches to a full-blown battle scene, kind of like directing a mini-movie, but cooler.
1.How do you start planning the visual effects for your projects?
My main motivation for starting personal fx sketches is to participate in challenges organized by specific art communities. The driving force behind creating this sketch was to submit it to the first-ever community competition hosted by the Korean Game VFX Artist Community.
Most of these challenges are centered around a specific theme. In this competition, the theme was ‘wind’. This inspired me to incorporate elements related to wind, such as the Western windmill, and to derive keywords like ‘movements of the water pump’.
The conception of the entire sequence begins with a simple sketch. I draw out the flow of the battle, the interactions between characters, and a rough idea and composition. In this process, I complete the idea with a sketch at the level of a doodle. It feels like creating a storyboard for a movie.
2. What tools did you use?
I have been involved in projects using the Unreal Engine in the industry for a long time. Therefore, I also use the familiar Unreal Engine for my personal sketches.
The primary resource creation tools I use whenever I work on a sketch are as follows:
Firstly, I use Adobe Substance Designer for the production of VFX textures.
There are several benefits to generating FX texture sources with Substance Designer.
We, as real-time game VFX artists, primarily use Seamless textures due to the common use of techniques that offset or distort the texture’s UV coordinates in the material for FX elements. The texture production process in Substance Designer provides effective convenience features related to Tiling, which allows us to produce texture resources for VFX efficiently. Furthermore, its procedural creation base enables rapid testing of various shapes by continuously adjusting each node parameters and source images.
Secondly, I use Blender for 3D modeling of FX elements and character animation. Blender, a freely accessible 3D tool without a license fee, is widely used among indie game developers. This has led to an active community and a wealth of readily available reference materials. Additionally, it provides convenience in finding solutions when issues arise.
Lastly, to increase the overall density of VFX, I use smoke resources simulated in Embergen and export them as flipbook textures.
3.Did you do any post work on it? any retiming?
I did not do any post-processing or retiming using a video editing program in this sketch ( such as adobe premiere pro or aftereffect ). The Unreal Engine’s level sequence editor provides a function that allows you to arbitrarily adjust the Unreal post-process material value animation and sequence playback speed for time adjustment.
The screenshot above is an example I used to control the post-process. I created a climax post-process material for this sketch. The parameter values of the post-process material were controlled through the MPC (Material Parameter Collection) asset, and the MPC can also be controlled through the Unreal sequence editor.
4.Anything you wanna share briefly about scene setup, lighting and rendering?
Whenever I work on a new sketch, I experiment with various lighting environments and floor textures.
The main goal here is to showcase the VFX design, so I keep the environment as simple as possible. If possible, it’s best to set the overall lighting to low saturation. By setting the overall atmosphere to low saturation, you can create a dramatic effect by blending high saturation lighting at the climax of the FX sequence later.
To focus on the VFX presentation, it’s good to set the entire light of the scene to be dark. I usually set the intensity of the Directional Light to about 0.25 lux. One thing to note here is that if the screen is too dark, it can be difficult to properly understand the character’s movements, and the density of the VFX may appear weak. Therefore, it is advisable to set the Skylight and Ambient Cubemap to a low intensity additionally to clear outline the overall elements.
5.What's the trickiest part you've faced in your recent work, and how did you tackle it?
When designing VFX, the most time-consuming and trickest part is the process of implementing all the FX elements that were initially conceived into the engine, and then polishing until a satisfactory result is achieved. If you blindly increase the intensity of the VFX elements or try to directly add various FX elements in the engine, you may end up with a messy visual that deviates from the original design or has a blurred shape.
Therefore, once the design has progressed to a certain level, you need to start carefully handling colors, brightness, and FX elements. The process of directly adding elements in the engine and checking them takes a lot of time, so a more efficient method is needed. So, when the design has progressed to a certain point, I capture a screenshot and bring it to Photoshop for retouching with a brush. This method can reduce the time wasted unnecessarily in the engine and allows you to test various modifications in a short time.
When the design reaches almost the completion stage, there comes a point where no further direction is visible. I often use the expression that the design becomes too familiar to the eye. If you look at the same design for a long time, at some point, the design becomes so familiar that strange parts do not catch your eye.
At that moment, just press Ctrl+S, save and close the project. And then take a break and come back. You can take a nap, collect art references, or play a game that you’ve been putting off. You need to refresh first so that the elements that were not visible can be seen properly again.
6.Is there anything else regarding your workflow that you would like to share?
These are Niagara systems placed in the level. If the number of emitters within a single Niagara system becomes excessively large, I tend to separate some and create a new system. This way, when modifying the Niagara system, I can reduce the system compile time and it is more convenient to check when modifying FX elements individually.
Lastly, I present a comparison shot of the initial design and the final version of this sketch. When designing FX, it’s beneficial to capture each version. This way, it’s easier to identify elements to improve and shortcomings in each version, which aids in finding a better design direction.
