Blender Anime-Styled NPR In 5 Concepts
Blender has seen gradual use in anime in recent years, corollary to the advent of CGI in Japan. The wider context is found on the 3D software market, where Blender’s open-source business model is an anomaly among the likes of Maya and 3ds Max, that are more subscription-based products. An anime industry veteran like Mitsuo Iso uses the software, and it was used by Shouta Goshozono (animator, episode director, storyboarder, key animator) on the critically acclaimed Ousama Ranking. What makes possible this use of Blender in 2D animation, is I believe what is captured by the idea of NPR. It is short for Non-Photorealistic Rendering, as opposed to the hyperrealistic approach found in PBR — Physically-Based Rendering — , what characterizes Unreal Engine and Unity’s possibilities for real-time physics-based ray tracing, making AAA games super immersive.
To go further on a gaming tangent, the console market has seen the arms race to innovate on more performant and stunning graphics for decades now, but the trend to turn to hyperrealism has left behind a suspension of disbelief that many gamers hold with nostalgia to this day. Which is why NPR in games like Borderlands appears so lively, filled with artistic authoring. I posit that this very sense of wonder is what makes animation as an art form commercially viable, especially with Spider-Man: Across the Spider-Verse echoing that much in the West. It is always interesting to see that a technology revolutionizing what occurs in videogames is wide-ranging into anything involving screens, because it showcases just how much impact the gaming and console markets directly have on the advent of computer graphics. And we have all clearly seen during lockdown just how much of a market there could be for entertainment, so just imagine what growth lies in store for NPR…
But what is NPR? “An area of computer graphics that focuses on enabling a wide variety of expressive styles for digital art, in contrast to traditional computer graphics, which focuses on photorealism. NPR is inspired by other artistic modes such as painting, drawing, technical illustration, and animated cartoons. NPR has appeared in movies and video games in the form of cel-shaded animation (also known as “toon” shading)” Because of two-dimensional influences, we can understand that it fits well with the animanga aesthetic, upholding a cultural legacy within the new technological era. Depth and lighting are toyed with so as to make things pop out.
Blender, being a 3D software focusing on democratizing artistic solutions worldwide and for free, benefits from an active community in part thanks to its open-source status, making it one of the connecting nodes for the democratization of NPR itself. This article focuses on the software to participate to this collective endeavor, as I firmly believe educational content that can empower people can change the world in a more creative and constructive direction. My post-mortem animation article also provided a bit of additional context for this one to come to fruition. Anyway, here ensue 5 concepts that you can reproduce in Blender to grasp NPR both in theory and in a hands-on fashion.
Outlining. Any anime or manga afficionado with enough discernment will find it in themself to praise outlines. The clarity with which a character stands out from the background is very desirable. What’s more, you can play with both the thickness and the hue or saturation of the outline to characterize things about the character, like mood or personality. The subtle use of an outline that chromatically fits the character you’re going with can have a big payoff. For now, all worked for 2D too, so why do outlines work out well in 3D? Fundamentally, an additional axis for depth is added, and it changes everything. However, by analogy with the cultural legacy of 2D visual arts, the outline can filter out some of the considerations about depth that PBR can introduce. In Blender, it is an effect you can achieve with a material set to an Emission shader with the color settings you want your outline to be (you can also choose to do a gradient with more magic in the Shader Editor), and then using a Solidify modifier to shape out your outline’s thickness (you may need to toy with offsets). However, there is an additional way which I still haven’t tried out to create outlines for a character, using the Grease Pencil. DillonGoo Studios’ Dillon talked about it when mentioning real-time lineart at a panel talk at Blender Conference 2022.
Goo Engine, a Blender fork or custom build, is the next concept I want to mention. “Goo Engine is our custom build of Blender that was made specifically to our team’s needs. Our team specializes in making 3D anime in Blender, and we have made our custom build available for others to do the same” In other words, it is a wide-ranging solution that aims at catering to the anime artform. Because anime production is stressful, it means that the solution to this problem-solving industry is stressed — stress-test is a term in a wide range of domains like engineering, that simply means to make a system undergo pressure to see if it’s resilient. And to see a community-building entity crystallizing the ongoing advent of PBR in the anime industry releasing a custom build to cater to this very problem-solving is worthy of interest. So that’s why I decided to include it as one of the concepts to get closer to getting NPR, as it’s also reliant on builds that change the paradigm of the software itself.
Flat colors. Toon-shading is characterized by the use of flat colors instead of a linear interpolation between two shades, something that would better represent the behavior of light in the real world, following of course the idea of light falloff. PBR obeys it as it wishes to depict physics, including the law of conservation of energy. There are two ways to use toon-shading in Blender, the easiest, coming out of the box is Toon BSDF in the same place as you’d find the Emission for a material. But the method I recommend the most is to use a Color Ramp node as you get to precisely choose a gradual palette, better for authoring purposes — especially as you can further use the output of the Color Ramp for even fancier stuff, like making a part transparent under a certain threshold, useful for a real-time (procedural) fire blast visual effect for instance.
Compositing. Compositing can be done both in post-production or in real-time thanks to Blender, and it basically helps to add lighting effects and color correction to your animation. This is the part of Blender where lighting skills help out, if you have a background in photography or something. The fire blast effect tutorial I mentioned uses Eevee as an engine with the Bloom rendering, whereas you would have to use Glare in the Compositing workspace if you decided to go with Cycles. This difference means that the ray tracing Cycles fundamentally wouldn’t behave like the rasterized Eevee. Even if you can use Bloom in real-time with Eevee, the documentation specifies that “Bloom is a post-process effect that diffuses very bright pixels. This mimics lens artifacts of real cameras. This allows a better sense of what the actual intensities of the pixels are.” At the very least, compositing can add flashiness to your animation, and great compositing is at work in the anime artform, so it’s one of the concepts you can make use of to approach the anime style with Blender. I also saw an aura outline done with a plane behind a model to mimic JoJo’s aura compositing, an idea that can make real-time, procedural compositing possible too.
Models and their character designs can go a long way to achieve NPR too. Anime-styled NPR works out better in creating suspension of disbelief if you use models that follow the artistic tradition. This goes with both anatomy and facial expression. To be quite honest, clothing is also something you can make use of, like gothic lolita clothing or a sailor uniform… When it comes to anatomy, anime characters are designed in 3D to look flatter, and the jaw for a profile view is supposedly distinctive. There are also more obviously the eyes and the nose, but the neck can be rather small too, like Lumine in Genshin Impact whose neck once made me freak out. Since the anime style evolved over time, I guess character designs will age no matter what. The MMD community has discovered Blender and there is now an add-on to import PMX models with a repository on GitHub that even supports Blender 3.6 LTS, meaning anime-styled character designs have even more of a place in understanding NPR in Blender. As for facial expressions, that depends more on the rigging of your model.
Let’s conclude this quick overview of Blender anime-styled NPR with 5 concepts. We have seen that outlines could subtly make your character pop out more, in inheritance of the animanga aesthetic. Further working out the 3D addition of a depth dimension, the use of toon-shading could break out the illusion of reality that a light falloff provides. Character models and designs are tied together, and to create an anime-styled NPR aesthetic, using anatomy, facial expressions and clothing reminiscent of the popculture you take inspiration from can go a long way — especially facial expressions, dependent on anatomy, as they’re the reason why anime characters have kind of flat faces. Compositing can help out recreating some of the effects anime is known worlwide for in some subgenres like shounen, which can be done either in real-time, procedurally, or in post-processing. And finally, the last concept is that of a custom build or fork, as Blender is open-source and Goo Engine seems to pave a new way for NPR. Though the MMD import add-on, like the Sketchfab one, ensuring interoperability with Blender, are also parts of this custom-build philosophy… I hope you will have learnt something as I delineated just some of the perspectives the software can help you with to recreate the illusion of 2D and the sometimes lost sense of wonder animation comes with.
