Quad

A quad (short for quadrangle or quadrilateral) is a face with four vertices and four edges. Blender's manual notes that quads "deform well" and "are therefore preferred for animation and subdivision modeling" (Blender 3.1 Manual: Mesh Structure). In the engine, every quad becomes two triangles.

#Why quads matter

Quads make loops. When every inner vertex of a quad grid has four edges, edges line up into continuous edge loops and edge rings. Loops only stop at poles, vertices with three, five or more edges (Blender 3.1 Manual: Mesh Structure). Loops make modeling faster: you can select, slide, bevel and cut along them in one click. See edge flow.

Quads subdivide predictably. The most common subdivision method, Catmull-Clark, is designed around quads. CG Channel describes it as the scheme that can be applied to meshes that are "mostly or entirely quads", whereas the Loop scheme for triangle meshes requires them to be "purely triangular" (CG Channel: Pixar releases OpenSubdiv 3.4). University lecture notes on subdivision describe Catmull-Clark as operating on quadrilateral meshes and treat vertices with other than four edges as special "extraordinary" cases (University of Cambridge: Further Graphics: 5. Subdivision surfaces). See subdivision surface modeling.

Quads still end up as triangles. The GPU "only deals with triangles", so every quad is split in two on import (Unreal Engine Documentation: FBX Static Mesh Pipeline). A quad has two possible diagonals, and on a bent quad they give different shapes. See triangulation.

#Common mistakes

• Treating "all quads" as a rule for every asset. It is a rule for subdivision and deformation, not for static game props (CG Cookie forums: N-Gons).
• Forgetting that quads have a diagonal. A non-planar quad shades differently depending on how it is split. See triangulation.
• Forcing quads with bad poles. Turning every triangle into quads can add awkward poles in visible places. Fricker warns that poles can cause subdivision errors and deformation problems (CG Cookie forums: Tris vs Quads for videogames). See pole.
• Leaving quads in a mesh you bake and then letting the engine triangulate differently. See triangulation.

#In different tools

• Blender. The Triangulate modifier splits quads with a choice of methods: Beauty, Fixed (1st to 3rd vertex), Fixed Alternate (2nd to 4th), Shortest Diagonal and Longest Diagonal (Blender 4.0 Manual: Triangulate Modifier). The Statistics overlay shows face and triangle counts, so a pure-quad mesh shows exactly twice as many triangles as faces (Blender 3.5 Manual: Viewport Overlays).
• Maya. The Poly Count HUD lists faces and triangles separately (Maya 2026 Help: Heads Up Display (HUD) Options).
• Unity. The model importer has a "Keep Quads" option that will "stop Unity from converting polygons that have four vertices to triangles" (Unity Manual 2018.2: Model tab). Leave it off unless a specific shader needs quads.
• Unreal Engine. Shows triangles only (Unreal Engine Documentation: Static Mesh Editor UI).

#Related terms

face · triangle · N-gon · edge loop · pole · topology · subdivision surface modeling · triangulation

#Further reading and watching