Renderer · interface

InstanceData

One base mesh drawn many times in a single call.

interface InstanceData

import type { InstanceData } from '@driftengine/core';

In depth

A field of grass is tens of thousands of copies of the same few triangles. Submitted individually that is tens of thousands of draw calls, which is the one thing a browser renderer cannot absorb; as instances it is one call and the GPU does the rest. This is what makes "dress the world" affordable at all.

Per-instance attributes advance once per instance rather than once per vertex (vertexAttribDivisor), so the base mesh is uploaded once and never again.

Properties

Name	Type	Description
`positions`readonly	`Float32Array`	3 floats each: world position.
`scaleAndYaw`readonly	`Float32Array`	2 floats each: uniform scale, then yaw in radians.
`tints`readonly	`Float32Array`	3 floats each: multiplied into the base mesh's colour.
`windResponse`readonly	`Float32Array`	3 floats each: how far this instance bends, how much the gust moves it, and a phase offset. More Per instance rather than global so a field does not sway in lockstep — uniform motion is the single clearest sign that foliage is a texture with an animation on it rather than many separate plants.
`capacity`readonly	`number`
`count`	`number`	How many instances are live; the rest of the buffer is ignored.