A Guide to Smart Material Creation with Corona Distance Map and Triplanar

Corona Distance Map and Corona Triplanar Map are two different material tools described in Chaos’s 3ds Max documentation. Distance Map generates colors, textures or masks based on the proximity of separate objects in a scene, while Triplanar Map projects textures along an object’s X, Y and Z axes. This guide is based on the 3ds Max descriptions in the Chaos documentation; the sources do not specify a particular Corona or 3ds Max version. A Distance Shader is also documented for Cinema 4D, but its parameter names may differ, so this guide uses the 3ds Max terminology.

How does Corona Distance Map work?

Corona Distance Map calculates the distance between objects added to the Distance from list and the surface to which the material is applied. You can assign separate colors or textures to near and far areas, with a gradual transition between the Distance near and Distance far values. This makes it possible to create effects such as dirt beneath windows, wear where objects meet, or waves around a shoreline.

One important limitation: the map is not intended to evaluate surfaces within a single object. Its calculation depends on the distance between the listed objects and other objects. Corona AO can also color concave or convex areas within a single object. So if your goal is to accentuate the corners of an object itself, Distance Map may not be the right tool.

How to set up Distance Map step by step

1. Choose the distance reference. Add the separate object or objects that should generate the effect to the Distance from list. For example, to create dirt beneath a window, you need to use the relevant geometry around the window as a reference. This list determines which surfaces the map measures distances from.

2. Set the near and far limits. Distance near defines the limit for the color or texture used close to the reference object; Distance far determines the appearance at a distance. The near and far inputs blend in the area between these thresholds. There is no single universal value: set the distances according to the scene geometry and the desired width of the effect. The documentation examples show values of 0, 250, 500, 1000, 2000 and 4000 for Distance near, and 0, 500, 1000, 2000, 4000 and 8000 for Distance far. These are examples for comparing different results, not fixed recommendations for every scene.

3. Define the near and far appearance. Set up the two ends of the transition by assigning colors or textures to Color near and Color far. For example, using a darker mask close to the object and a lighter value farther away creates a distance-based distribution. The map output can be used in materials or object properties; the source gives examples involving opacity, displacement and scattering distribution.

4. Check how interior surfaces are handled. When Color inside is enabled, a separate color or texture can be applied to surfaces inside the Distance from objects, based on the shading normal direction. Precise mode identifies interior regions more reliably. Fast mode can be quicker, but only gives accurate results on simple meshes; the documentation notes that Fast is generally unnecessary unless compatibility with older scenes is required.

5. Vary the distance with Distance scale. This input multiplies the near and far distances by the color values of the connected map. White, or a value of 1, leaves the distances unchanged; lower values reduce both distances. This lets you introduce noise or variation into the distance calculation. Setting up the basic transition first and adding this input afterward makes it easier to track which setting is changing the result.

Unlike Corona AO, which is calculated during rendering, Corona Distance Map is calculated once, updates in real time in the viewport, and produces noise-free results in renders. It is also suitable for uses such as distribution maps, displacement or bump; Corona AO does not offer the same flexibility for these examples.

Triplanar texturing without UVW unwrapping

Corona Triplanar Map projects textures along an object’s axes, helping reduce the seams and stretching that can occur with conventional UVW mapping. You can use a separate map for each of the X, Y and Z axes. If you want the same texture on all axes, enable Use map X for all axes; when this option is off, the Y and Z slots are also used.

Blending Amount controls the transition between axes. Higher values can make seams appear smoother, but may increase texture blurring. Lower values produce a sharper transition. If a Blend Map is used, the Amount value is overridden. The choice of Mapping space also matters: Local space ties the mapping to the object’s pivot; World space uses the world axes even if the object is rotated. Reference node space uses another object to control the mapping.

Scale sets the texture’s size in world units. Increasing the value reduces the number of repeats; decreasing it increases the number. Offset and Rotate change the texture’s position and rotation. However, Triplanar Map’s effect is not visible in the viewport preview. Don’t assume the mapping has failed based only on the viewport; inspect the result in a render.

Using these tools in an architectural visualization workflow

In interior scenes, Distance Map can be used to mask dirt beneath windows or material changes around parts that are close to one another. In facades, landscapes and organic forms, Triplanar Map can speed up texture testing on surfaces that have not been UVW unwrapped. Technical models with both sharp corners and curved surfaces are also among the use cases for Triplanar shown in the documentation.

These tools do not replace modeling or UVW preparation in every situation. You need to choose the right separate objects for Distance Map to reference, and the choice of local, world or reference space for Triplanar should suit the object rotations in the scene. In particular, if a scene will be transferred to another application, don’t assume that these map features are supported in the target software. The sources here describe how the maps work in Corona; they do not guarantee compatibility with other software.

Common mistakes

• Using Distance Map to calculate indentations and protrusions on the surfaces of the same object; the map does not work within a single object.

• Expecting a very wide or narrow transition without checking the near and far thresholds; the area between them blends the two ends.

• Using Fast mode on complex meshes; according to the documentation, this mode only works accurately on simple meshes.

• Assuming the setting is not working because you can’t see the Triplanar result in the viewport; the effect is not visible in the viewport preview.

• Overlooking blurring while increasing the Amount value; smoother blending can lead to a blurrier texture.