VRay Material Bump and Normal Mapping Lesson Introduction

V-Ray Material: Bump and Normal Mapping

Lesson Introduction – Orientation • This presentation will take you through setting up bump and normal maps for the base V-Ray material VRay. Mtl • This information centers around the parameters under the Bump and Normal mapping rollout for VRay. Mtl • The lesson topic is approximately 30 minutes in length • Presentation covers all 3 Learning Cycles for the Lesson Topic – Lecture, Demonstration, and Activity

Lesson Topic: Bump and Normal Mapping • Objective – We will use bump and normal mapping to alter a material in the scene • Develop a look for the owl statue • Assign textures as bump and normal maps to create different looks • Outcome – You will understand how to manipulate the bump and normal mapping parameters of the base V-Ray material VRay. Mtl

Lecture: Terminology • Here’s some terms to be aware of when thinking about bump and normal mapping – Normal – An imaginary arrow that points directly out from a face on a 3 D object – Object surface normals are calculated automatically by the software – Renderer uses normals to determine how highlights and shadows are generated in rendering – Normal mapping – A type of bump mapping that makes use of surface normals – Space – Normal mapping uses terms like world space, object space, and tangent space to refer to the map’s orientation within the scene

Lesson Topic: Bump and Normal Mapping • Uses maps to create effect of bumpiness • Primarily a light effect – doesn’t actually affect the geometry • Renders highlights and shadows to fool the eye • Works with any kind of map: bitmaps or procedural textures like fractal

Lesson Topic: Bump and Normal Mapping • Pros • Renders faster than modeled detail • Easier to adjust and tweak • Cons • Not suitable for large protrusions • Does not affect shape of silhouette

Lesson Topic: Bump Maps • Grayscale values determine bumpiness pattern • • White pushes out/up, black pushes in/down Uses UVs to determine direction

Lesson Topic: Normal Mapping • Colors set angle of bumpiness • Blue pushes in/out along surface normal • Other colors push in other directions

Lesson Topic: Normal Mapping • Choices of “space” to use • • Object space suitable for non-deforming objects (eg. buildings) Tangent space suitable for deforming objects (eg. characters) World and screen space rarely used Different spaces use different color schemes

Lesson Topic: Bump and Normal Mapping • Bump Mult • Sets the intensity of the bump effect • Negative values push in opposite direction

Lesson Topic: Bump and Normal Mapping • Bump Shadows • Subtle effect of self-shadows within bumps • Bump Delta Scale • Sharpness/fuzziness of transitions from black to white

Lecture Conclusion: Bump and Normal Mapping • Bump Mult – Sets degree of influence • Normal map space – Determines how normal map works with surface • Bump Delta Scale – Sharpness or fuzziness of bump effect • Bump Shadows – Self-shadows within bumps

Time to see it work! • Demonstration Cycle! • Watch while I demonstrate how to set up bump and normal mapping

Time to do it yourself! • Activity Cycle! • Now it’s your turn!! • Use the provided scene file to set up bump and normal mapping for the owl • The next slide provides some specific values I used for your reference

Dialing in the right values • Reflection Color – white • Map – NM_01. tif • Map Type – Normal map in tangent space • Bump Mult – 1