Batching and vertex shader custom chunks

Glenn_Ko · June 5, 2018, 5:12am

var chunks = material.chunks.
chunks.transformVS = " my custom code here "…

When i activate batching for a particular thing with this.app.batcher.generate()… my chunks.transformVS custom code no longer runs.

Why?

Yikes:

github.com

playcanvas/engine/blob/stable/src/scene/batching.js#L908


// Create mesh
mesh = new pc.Mesh();
mesh.vertexBuffer = vertexBuffer;
mesh.indexBuffer[0] = indexBuffer;
mesh.primitive[0].type = batch.origMeshInstances[0].mesh.primitive[0].type;
mesh.primitive[0].base = 0;
mesh.primitive[0].count = batchNumIndices;
mesh.primitive[0].indexed = true;
mesh.cull = false;


if (dynamic) {
    // Patch the material
    material = material.clone();
    material.chunks.transformVS = this.transformVS;
    material.chunks.skinTexVS = this.skinTexVS;
    material.chunks.skinConstVS = this.skinConstVS;
    material.update();
}


// Create meshInstance
var meshInstance = new pc.MeshInstance(this.rootNode, mesh, material);

Looks like BatchManager has it’s own this instance of transformVS that was preinitializrd and stuck to the default pc.shaderChunks version!!.. bleh… but all it does is prepends #DEFINEs for bone limits and DYNaMIC batch flags to the existing chunk , so why not this should be done by prepending the bone/dynamic flags to any existing custom material.chunks.chunkName ( if available ) during batch creation, and not be stuck to default replacement? Looks like I got to do some heavy method replacements/overhauling to pc.BatchManager.

I also find that storing a this.shaaderRefeence is pointless anyway if it can be accessible globally from pc.shaderChunks.etc, anyway.