9

Troubleshooting Normal Bump Maps 151
the most straightforward and simplest workflow
involves these steps:
1. Create a detailed, high-resolution model.
2. Create a simpler, low-resolution model.
The low-resolut ion model should have
thegeneralshapeandoutlinesofthe
high-resolution model, and typically it should
be a bit sm al ler, so that projected detail in the
high-resmodelwillappeartobeaboveits
surface.
3. Select the low-res model.
4. Choose Rendering > Render to Texture.
The Render To Texture dialog appears.
5. On the Objects To Ba ke rollout, in the
Projection Mapping group, click Pick.
Aselectiondialogappears.
6. Choose the h igh-res object, and then click Add.
3dsMaxappliesaProjection modifier (page
1–769) to the low-res object.
7. In the Projection Mapping group, turn on
Enable.
Note: At this stage, often you will click Options
to display the Projection Options dialog (page
3–165),whichhasavarietyofsettingsforhow
to generate the projection.
8. On the Output rollout, add a NormalsMap
element (see Baked Texture Elements (page
3–146)). Assign Bump as its target m ap slot.
9. IntheSelectedElementsUniquesettingsgroup,
turn on Output Into Normal Bump.
10.Click Render.
3dsMaxrenderstheNormalsmap,which
stores normals data f rom the hig h-res object.
As for other kinds of texture baking, it creates
a Shell material and applies that to the low-res
object, with the Normals map assigned as the
bump component.
Components of Nor ma l B u mp M a pping
In the 3ds Max interface, controls for normal
bump maps appear in three locations:
• T h e Ren d e r To Tex t u re dia l o g
Specifically, normal projection controls are
found on the Objects To Bake rollout (page
3–158) and the Output rollout (page 3–160).
•TheProjection modifier (page 1–769)
You can apply a Projection modifier yourself, or
let Render To Texture do so automatically.
•TheNormal Bump map type (page 2–1731)
Render To Texture creates this automatically if
youturnonOutputIntoNormalBump(step
9, above).
Viewing Normal Bump Maps
If your display driver uses DirectX 8, you can view
normal maps in v iew ports by using the Metal
Bump shader (page 2–1614).Ifyourgraphics
driver is DirectX 9, you can view normal maps in
any shaded v iewport. See Direct3D Dr iver Setup
Dialog (page 3–843).
If your display driver is Software or OpenGL, you
can’t view normal maps in viewports. However,
youcanstillrenderthemandusenormalmapping
in renderings.
Nor mal Proj ection with Sub-Object
Selections
You can associate different sub-object select ions
with different high-resolution geometry. See
Reference Geometry Rollout (Projection Modifier)
(page 1–772).
Tr oubles hootin g Norma l B ump
Maps
Because of the variety of geometry and different
situations that can ar ise, normal bump maps