Instancing draws one shape many times. Each copy has its own matrix for position, turn, and size.
Look at Draw calls. The number stays at 1. The computer draws every copy in one pass. The copies share one shape. Only their matrices differ.
Select a block
Click a block, or type its number. The rightmost column of the matrix is the position of that copy.
4×4 matrix for this copy. Read each row from left to right. The rightmost column is the position.
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Color shows height. Color is not in the matrix. Taller blocks are darker.
Where this is used
A game or a film draws many trees, blades of grass, or people from one model. A particle effect often draws many copies of one small shape. An environment artist and a technical artist set this up.
A city model or a digital twin repeats buildings and street lights. A GIS developer or a digital-twin developer builds that view.
An architecture model can repeat every seat in a stadium. A CAD viewer repeats bolts and panels from one part.
A science viewer can draw many atoms as copies of one sphere. A scientific visualization developer builds that picture.
One draw call keeps the picture steady on a phone, a laptop, or a VR headset. A VR headset needs a high frame rate so the view stays comfortable.
Common mistakes
Each copy is not a new shape. The copies share one box, and only the matrix changes.
The rightmost column is the position of that copy. It is not the turn.
More copies do not add draw calls. This picture stays at one draw call.
Color shows height. Color is not stored in the matrix.