Proper lights for VRayToonMTL

[isoparmesan]

I just started messing around with the VRayToonMTL, and it seems like I can't get the cel shaded "toon" look using VrayLightRect or VrayLightSphere. The VrayLightRect will produce results that mostly adhere to the diffuse ramp, but has soft transitions between the ramp colors, and soft shadows. It seems to work as expected with Maya's built in Directional Light, or with V-Ray Sun. Is this by design? Or, is there a way to have hard transitions using normal rect lights?

I'm on Maya 2019.2 using V-Ray 4.3. I'm on MacOS 10.15.5.

I've included examples of what I'm talking about.

This is the result with the Maya directional light, and how I would expect it to look with all lights.


This is how it looks with VrayLightRect

[tsvetomira.girginova]

Hello isoparmesan,

As you declare yourself, V-Ray Toon Mtl has a different attitude by using different light source types.
Toon style is a kind of non-photorealistic rendering (NPR).
Corresponding to this, it requires a different approach than realistic-style renders.

To get a typical cartoonish style renders however it’s important to:

• use non-physical Cameras and Lights with no exposure control
• disable Global Illumination, Environment Maps and additional lights sources
• use single directional key light like Maya Directional Light, which illuminates the scene from specific direction

This approach will result in fast results with an easier scene setup.

V-Ray Lights and Cameras are created to be physically accurate. That’s why you could use them, but it requires more tuning and adjustments, like making the lights Directional, decreasing the Multiplier and removing the exposure control. Using the standard Maya lights for this particular scenario might ease your workflow.

If you want to have not only objects with V-Ray Toon Mtl in your scene and more lights with different directions (for the objects with V-Ray Toon Mtl only Maya Directional Lights), just exclude these lights from the other objects. Оtherwise, they may disturb the Toon effect. It depends on your project and what you want to achieve.

We’re preparing a step-by-step setup article, which will explain all the details.


Stay tuned and TOONed!


Best regards,
Tsvetomira

[isoparmesan]

Got it. Glad to know I’m not crazy

is it possible to get the hard toon shading like my first photo with a non parallel light source (like a point, area, or rectangle light)?

[tsvetomira.girginova]

Hi again,

It depends on your scene and the effect you want to achieve.

Beside Maya Directional Light (the best main choice), for this kind of hard toon shading you could use also:

• Maya Point Light, because of its small size
• very small Maya Area Light (try Scale=0.1 in all directions)

You mentioned rectangular lights.
That’s why I’ll propose one more option - try VRayLightRect, if you want to achieve similar results with V-Ray Lights.
Follow these steps:

1. Set the Directional value to 1 from the Directionality section
2. Check the Preview mode to be Selected or Always
3. Make sure that all objects are within the light scope (the Preview helps for this)
4. Decrease the Multiplier to 0.5
5. Render!

Test these lights and choose the most suitable for your workflow.

Best regards,
Tsvetomira.