ArrayOfDisplacement

ArrayOfDisplacement is a term used in computer graphics to refer to a collection of displacement values that modify the geometry of a surface. The array provides per-element offsets that, when applied, displace vertices from their base positions to create detail such as wrinkles, grooves, or profile variation without increasing base polygon count.

Data representation: Each element can be a scalar or a three-dimensional vector. In practice, many pipelines store as three floats per element (dx, dy, dz) representing an offset in object or tangent space; others store a single float representing a displacement along the surface normal. The array is typically associated with the same topological set as the mesh (one entry per vertex, or per texel/patch in a tessellation pipeline).

Usage: During rendering, the array is sampled in a vertex shader or a tessellation evaluation shader. If the displacement is a vector, the displacement is added directly to the position. If scalar, it is multiplied by the surface normal (and sometimes a scale factor) before being added. This is a generalization of displacement maps and is used in both real-time and offline rendering.

Origins and storage: ArrayOfDisplacement can be authored by artists, baked from high-detail geometry, or generated procedurally. It may be stored as a dedicated vertex attribute, as a texture (displacement map), or integrated into a larger asset format such as GLTF, FBX, or custom engines. There are trade-offs between memory footprint and precision, and many pipelines compress or stream the data as needed.

Related concepts include displacement mapping, height maps, tessellation, and vertex attributes.