Houdini 20.0 Nodes Geometry nodes

Labs Decal Projector geometry node

Project a decal (localised piece of geometry and a texture) onto geometry.

Decals are a common feature in game engines. For example, say a small manhole cover texture is required at a single location on a large floor. Applying a massive texture across the entire floor to get enough resolution for the manhole cover is inefficient. To require re-uving the floor to define a region for the manhole is possible, but will require further edits if the location of the cover has to change.

Instead, game engines will provide a decal, providing a wireframe box as a GUI element to the user. The manhole cover is assigned to the decal, and the box UI is rotated, scaled, and intersected with the floor to represent where it needs to go. The manhole cover will be composited into the floor texture.

The gamedev decal projector sop replicates this workflow. Rather than composite the texture, a perfectly fitting polygon 'sticker' or 'decal' is made containing the required texture. This will adapt to to any changes of the underlying geometry, and can be merged with the original geometry.

Parameters

Transform

Translate

Position of projection plane.

Rotate

Rotation of projection plane.

Scale

Scale of projection plane.

Pivots

Pivot Rotate

Position of rotation pivot of projection plane.

Pivot Translate

Position of translation pivot of projection plane.

Uniform Scale

Scale of projection plane.

Match Image Aspect Ratio

Scale the projection by the Image’s aspect ratio

Base Color

Texture map used for decal base color.

Height Map

Texture map used for projection, ideally a grayscale 'heightmap' image. Note that this refers to a texture to be used as a heightmap, not a houdini heightfield node!

Strength

Multiplier to alter the strength of the heightmap.

Use Inverted Height as AO

When enabled the lowest parts of the heightmap will be darkened with a 2d ambient occlusion filter, useful to enhance detail and visually separate high and low parts of the heightmap.

Max Distance

Maximum distance the surface can be away from the projector handle. If the projection is further than this distance, the projection will be clipped.

Floating Distance

Distance to float the projection above the target surface. Ideally this should be as close as possible, but not so close that it causes flickering or Z-fighting issues.

Clip X

Clip or 'barn doors' for the left and right side of the projection.

Clip Z

Clip or 'barn doors' for the top and bottom of the projection.

Geometry nodes