Instanced Drawing (GPU Instancing)

Instanced Drawing (Instance drawing / GPU Instancing) is a technical term that is extremely important in rendering and optimizing game graphics (technical art). An explanation of an optimization technique that utilizes GPU hardware capabilities to draw duplicates of the same 3D mesh (e.g., tens of thousands of grasses in a meadow, thousands of soldiers, etc.) in a massively parallel manner while assigning individual positions, angles, and colors (Structured Buffer, etc.) with a one-time draw call.

An analogy in the real world: Instead of manually copying the same copy (grass model) one by one and delivering it to the site individually by truck, we send one ``completed stamp (mesh data)'' and ``coordinate list (position array) of tens of thousands of places to be stamped'' to the site, and a GPU stamp machine simultaneously stamps tens of thousands of times in 1 millisecond for simultaneous duplication printing

Instance drawing is a method that completely eliminates the need for the CPU to send tens of thousands of commands to the GPU, ``Draw this grass here,'' when arranging a large number of copies of objects of the same shape (3D mesh). , is the ultimate parallel mass copying technology that instantly sends a ``grass mold (mesh data)'' and ``a list of tens of thousands of coordinate addresses to place it'' to the GPU with a single command, and uses the GPU's ultra-high-speed replication stamp function (instancing function) to instantly ``copy and paste'' tens of thousands of pieces of grass on the spot.'' CPU communication congestion (draw callbottleneck) is completely eliminated, allowing you to build ultra-dense nature and large armies that exceed the limits of appearance with incredible lightness.

Detailed mechanism and operating principle

Turn on "Enable GPU Instancing" in the material's insector, or call `Graphics.DrawMeshInstanced` or `Graphics.DrawMeshInstancedIndirect` on the C# side to instantly send tens of thousands of position coordinate arrays to the GPU. href="/article/term-draw-call">Draw call to draw in one stroke.