Bump Map Node

Bump Map takes a grayscale image (bright pixel = high relief, dark pixel = low relief) and outputs a 3D material that perturbs the surface normals. The result: highlights and shading behave as if the surface really had relief, without adding a single polygon.

The illusion works very well when seen head-on or slightly oblique. At grazing angles, the lack of real geometry becomes visible (the silhouette stays smooth).

• Effects Library: Tools > 3D > Texture > Bump Map
• Quick add: right-click in the Node Editor → Add Tool > 3D > Texture > Bump Map

Height Map (grayscale)

Grayscale image. Bright pixel = high, dark pixel = low. Easy to create (just paint in gray). The node computes the perturbed normals from the gradients.

Normal Map (RGB)

Color image that directly encodes the normals (X/Y/Z in R/G/B). Typically purple-blue. More accurate than a height map but needs a baking tool (Substance, xNormal) to create.

The Fusion Bump Map accepts both formats through the Source Image Type toggle: Height Map or Bump Map (= an already computed Normal Map).

• Input (orange) - required. 2D image (grayscale height map or RGB normal map), or the output of a Create Bump Map.

Classic workflow:

FastNoise ──→ Bump Map ──→ Blinn (input Bump) ──→ Shape 3D (MaterialInput)

Or with an existing texture:

Loader (brick height map) ──→ Bump Map ──→ Blinn (input Bump) ──→ ...

Source Image Type

• Height Map - default mode. Fusion computes the normals from the luminance gradients.
• Bump Map - the input image is already an RGB normal map. The node passes it through as is.

Filter Size

Size of the filter used to compute the normals from the height map. Larger filters = softer details; smaller = finer but potentially noisy details.

Height Scale

Controls the strength of the relief. Higher = more visible relief. Watch out: too strong and the effect becomes unrealistic (the surface looks liquid or swollen).

Height Channel

Image channel used as the height source (Red, Green, Blue, Alpha, Luminance).

Clamp Z Normal

Limits the Z channel of the normals (prevents normals pointing the wrong way).

Wrap Mode

Edge behavior for repeated tiles. Lets you build seamless textures.

• Brick wall - brick texture (color) on Diffuse + a height map of the joints on Bump Map. The joints look recessed without adding polygons.
• Stylized skin - high-frequency fractal FastNoise → Bump Map with a low Height Scale → skin micro-relief on a Text 3D or a Shape.
• Tree bark - grayscale bark texture, Bump Map with a high Scale, green-brown Blinn.
• Rough fabric - grid pattern noise → subtle Bump Map → gives the feel of a woven fabric.
• Engraved 3D logos - grayscale logo texture → Bump Map on a metal plane = a convincing engraved plate.
• Rocky terrain - combine with a Displace 3D (real large-scale deformation) + Bump Map (micro-details) for a rich render without exploding the polygon count.

• Moderate Height Scale - it is tempting to crank it up to see the effect. Prefer subtle values (0.01-0.1) for a believable render.
• Grazing view = broken illusion - the silhouette stays smooth since there is no real geometry. For large relief seen at an angle, use Displace 3D.
• Combine Bump + Displace - Displace for large undulations (which affect the silhouette), Bump for micro-details (which need no polygons). A pro technique.
• Third-party Normal Maps (Substance, xNormal) - if you have normal maps from a texturing app, use Bump Map mode (not Height Map).
• A light Blur before the Bump Map softens a height map that is too noisy. It avoids artifacts on the normals.
• The Bump Map render depends on the lighting - an unlit object does not show the relief. Add at least one Directional or Spot Light to see the effect.