Differences between Displacement and Bump
Displacement physically displaces the mesh to which it is applied, while bump creates the illusion of depth and texture on the flat surface of a 3D model.
Difference between Displacement (left) and Bump (right).
Using Displacement with Corona in 3ds Max
Open the Slate Material Editor by pressing M or by going to Rendering > Material Editor > Slate Material Editor.
In the Slate Material Editor, right-click in the empty space, and go to Materials > Corona > CoronaPhysicalMaterial to create a new Corona Physical Material.
You can find the "Displacement" slot in the Corona Physical Material's "Maps" section.
Put your displacement texture into the Displacement slot.
Using Displacement with Corona in Cinema 4D
- Open the Node Material Editor by going to Corona > Node Material Editor.
- Right-click in the Node Material Editor, navigate to New Material, and select the Corona Physical Material.
- In the Material Editor, go to the "Basic" tab and check the "Displacement" option to enable displacement. This action will reveal a new "Displacement" tab.
- Go to the "Displacement" tab and load your displacement texture into the corresponding slot.
Here is an example of how displacement can be used in Cinema 4D and 3ds Max to create realistic surfaces:
Material Setup of Brick Wall using displacement in C4D
Material Setup of Brick Wall using displacement in 3ds Max
Displacement Parameters in Corona for 3ds Max and Cinema 4D
Both 3ds Max and Cinema 4D have some similar displacement settings in the Corona Physical Material. Let's look at these settings and their effects:
- Min level: This setting determines the strength of the displacement effect for the dark parts of the texture.
In this example, only the dark areas are being affected by the "Min Level".
Max Level: This setting determines the strength of the displacement effect for the brightest parts of the texture.
In this example, only the bright areas are being affected by the "Max Level".
Water level: This setting acts as a cutoff threshold for displacement. If a part of the texture has a value below this level, the corresponding micro triangle will be removed.
In this example, the water level setting is cutting the geometry based on its value.
Animation and displacement
In Corona, the default displacement calculation method ("Screen size", in 3ds Max: Render Setup > Performance > Displacement; in Cinema 4D: Render Settings > Corona > Performance settings > Displacement) is optimal for rendering still images - it will look great and consume as little memory as possible, but it may not be suitable for animations. When using the Screen size displacement, it is tessellated dynamically for each frame based on the camera position, which can often result in visible flickering. Because of that, it usually makes more sense to switch to World Size displacement (in 3ds Max: Render Setup > Performance > Displacement > World size; in Cinema 4D: Render Settings > Corona > Performance settings > Displacement > World size), which will tessellate the geometry exactly the same way for each animation frame. This does, however, result in higher memory usage, so the displacement size should always be set to as high as possible.
- Don’t use a small displacement screen size value with large-resolution images, as this can result in very high RAM usage and slow parsing time.
- Only use the World Space displacement option when really needed – for example, if there is displacement flickering visible in the animation.
- Use autobump (it’s enabled by default), which will let you keep low displacement tessellation (and therefore save memory) without losing detail.
- You can use the Corona Displacement modifier in 3ds Max or a Corona Displacement Tag in Cinema 4D to apply lower-quality displacement to objects further away from the camera, and higher-quality displacement to the objects that are close to the camera, even if they are using the same material.
Example peak memory usage in a scene rendered in Full HD resolution:
- Displacement size 4px – 4,5 GB
- Displacement size 3px – 4,7 GB
- Displacement size 2px – 5,4 GB
- Displacement size 1px – 5,9 GB
Examples of using Displacement - a flat plane with a noise modifier and a material with Diffuse, Normal, Bump, and Displacement maps: