Merged

<Merged /> takes a { name: mesh } map and builds one instanced batch per entry. Any descendant, at any depth and in any component, joins one by key with <Instance batch="..." />.

That is what makes repeating a whole model cheap: a robot made of two meshes drawn 49 times is two drawcalls, not 98.

Usage

The model becomes its own component, and knows nothing about the batches beyond their names:

<script setup lang="ts">
import { Instance } from '@tresjs/cientos'
</script>

<template>
  <TresGroup>
    <Instance batch="Body" :position="[0, 0.6, 0]" />
    <Instance batch="Body" :position="[0, 1.6, 0]" :scale="0.6" />
    <Instance batch="Eye" :position="[-0.18, 1.7, 0.32]" />
    <Instance batch="Eye" :position="[0.18, 1.7, 0.32]" />
  </TresGroup>
</template>

The provider hands over the meshes and renders as many copies as it likes:

<script setup lang="ts">
import { TresCanvas } from '@tresjs/core'
import { Merged, useGLTF } from '@tresjs/cientos'
import Robot from './Robot.vue'

const { nodes } = useGLTF('/robot.glb')
</script>

<template>
  <TresCanvas>
    <TresPerspectiveCamera :position="[12, 9, 12]" />
    <Merged :meshes="{ Body: nodes.Body, Eye: nodes.Eye }">
      <Robot :position="[-2, 0, 0]" />
      <Robot :position="[0, 0, 0]" />
      <Robot :position="[2, 0, 0]" />
    </Merged>
  </TresCanvas>
</template>

Instancing a whole glTF

useGLTF gives you nodes, so instancing every repeated mesh of a model is a matter of picking the ones worth batching:

<Merged :meshes="{ Screw: nodes.Screw, Bolt: nodes.Bolt }">
  <Machine v-for="i in 20" :key="i" :position="layout[i]" />
</Merged>

The payoff is across models, not within one: twenty machines sharing two batches is two drawcalls.

Opting a node out

An <Instance /> is all-or-nothing per node: it uses the batch's geometry and material. When one node needs its own material, a different geometry, or its own shader, render a normal <TresMesh /> instead of an <Instance />. You trade one drawcall for full control over that node, and every other node stays batched.

Props

Exposes the named batch registry through instances.