Introduction


  • This lesson will take you through setting up displacement with V-Ray
  • This information centers around the basic displacement parameters
  • The lesson topic is approximately 25 minutes in length
  • Lesson covers all 3 Learning Cycles for the Lesson Topic – Lecture, Demonstration, and Activity

Contents


Overview
Available Materials
Lecture
Demonstration
Activity                                 
Additional resources 

 

Overview


Goal - Use various displacement parameters to create different looks

Objective – We will use several parameters to set up and alter displacement in a scene. Develop the look for a birdhouse model.       

Outcome – You will understand how to work with the displacement parameters to  create a specific look

 


 

Available materials


To set up the lesson follow the links below and download all available materials.

Lesson plan download
Presentation (Lecture) download
Demonstration tutorial 1 download
Demonstration tutorial 2 download         

Scenes & Assets download

 


Lecture



1. Terminology

Here are some terms to be aware of when thinking about displacement:

  • Displacement
    • The deforming of geometry based on maps
  • Subdivision
    • The dividing of geometry into smaller polygons

 

 2. Displacement vs. Bump Mapping


  • Displacement mapping alters the actual geometry
    • Interactively subdivides geometry
    • Suitable for large protrusion
    • Alters the edges of objects
  • Bump mapping does not alter the actual geometry

    • Primarily a lighting effect

    • Suitable for small bumps

    • Does not affect edges of objects

 

 



 

3. V-Ray Displacement


a) Displacement Workflow Overview

  • Add VRayDisplacement node to object via V-Ray Displacement button in V-Ray Shelf or by choosing Create > V-Ray > V-Ray Displacement in the Maya main menu
  • Assign a map to the VRayDisplacement node
  • Additional parameters available as Extra VRay Attributes (seen below)
  • Once displacement is set up for one object, you can add more objects in Outliner to receive the same displacement

 

 

 

 


 


b) Parameters that affect displacement

  • Displacement mat. (found in vrayDisplacement node) – this is the texture map
  • Extra Attributes added through Attribute Editor to the object itself:
    • Displacement Amount – adjusts how much the displacement affects the geometry as a factor multiplying the effect of the map
    • Displacement Shift – adds or subtracts a constant value to the map
    • Max subdivs – limits the amount of geometry subdividing to save memory and render time
    • Edge length – the lower the value, the more accurate the displacement at the cost of render time
    • Texture resolution – sets the resolution of the texture map being used
    • Water level – clips the geometry away (creating a hole) when the displacement map values fall below the specified value

 

 

 

 


c) V-Ray Displacement shelf button

  • Creates a VRayDisplacement node for selected object
  • Parameters for displacement are set within the node

 

 

 


d) Displacement mat. slot

  • Map that defines the displacement effect
  • Only grayscale values used

 

 


e) Rendering of displacement

  • Make sure that Displacement and Subdivision check boxes are enabled in Render Settings > Overrides > Geometry

  

  


f) Displacement Amount

  • Sets degree of displacement

 

 



 


g) Displacement Shift

  • Adds to the shift amount
  • Amount = multiplication, Shift = addition

 

 



 


h) Edge Length

  • Sets maximum edge length for subdivided surface
  • Smaller values make finer mesh, at a cost of render time

 

 



 

 

i) Max subdivs

  • Max number of subtriangles generated for each face during subdivision
  • Expressed as square root: Value of 8 results in max 64 triangles
  • Higher values = finer detail, lower values = faster rendering

 

 



 

 

j) Texture resolution

  • Sets resolution of texture used by displacement effect

 

 



 


Conclusion


 a) Water level

  • Visually clips the geometry below a specified planar level, as if the geometry were “under water”

 

 



 

 

b) Displacement mat

  • Sets pattern for displacement as grayscale values

c) Amount and Shift

  • Sets degree of displacement

d) Max subdivs

  • Sets max number of face subdivisions

e) Water level

  • Clips geometry

 

 



 

                                                                                                                                                                                                      

 

Demonstration


Time to see it work!

Watch while I demonstrate how to set up displacement.

Demonstration tutorial 1
Demonstration tutorial 2

                                                                                                                                                                                            

 



 

 

Activity



Time to do it yourself!

Use the provided scene file to set up and adjust displacement.

We have also provided a final scene for your reference.

 

 

Dialing in the right values

  • For planks:
    • Displacement mat. – Planks_Noise
    • Displacement Amount – 0.8
    • Displacement Shift – -0.4

 

Additional resources


Find more training resources listed below: