version: "1.0.0" name: reduce-draw-calls description: Use when a PlayCanvas app has too many draw calls or is CPU-bound, before hand-merging meshes or writing custom renderers.

Cut draw calls

Measure first with app.stats.drawCallCount or MiniStats; the per-pass app.stats.drawCalls breakdown fills only in profiler builds. Also halve the pixel ratio and call app.resizeCanvas(): if frame time drops, the cost is fill rate, not draw calls. Stop at the first rung that meets the budget and report before-and-after counts.

1. Stop drawing hidden things

An element at opacity 0 still draws. Set enabled = false.

2. BatchManager

Call app.batcher.addGroup(name, dynamic, maxAabbSize), then set batchGroupId on render, sprite, or element components. Use dynamic: false for geometry that never moves. Members join when enabled in the live tree, in any order, and groups regenerate automatically when membership changes. Call markGroupDirty(id) only after moving members of a static group. Manual AppOptions bootstraps must set batchManager.

3. Hardware instancing

Use this for many copies of one mesh and material with per-frame transforms. Build a buffer with VertexFormat.getDefaultInstancingFormat(device), one mat4 per instance, and call meshInstance.setInstancing(vb); instancingCount follows the buffer.

There is no per-instance culling. By default the group always draws; setInstancing(vb, true) culls it as one unit against a RenderComponent#customAabb covering every instance. Split large instance sets into spatial chunks. Custom vertex chunks need the INSTANCING path (override-shader-chunks). Start from the graphics/instancing-basic and graphics/instancing-custom examples.

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