three
Version:
JavaScript 3D library
73 lines (40 loc) • 1.4 kB
JavaScript
import Node, { addNodeClass } from './Node.js';
import { varying } from './VaryingNode.js';
import { nodeImmutable } from '../shadernode/ShaderNode.js';
class IndexNode extends Node {
constructor( scope ) {
super( 'uint' );
this.scope = scope;
this.isInstanceIndexNode = true;
}
generate( builder ) {
const nodeType = this.getNodeType( builder );
const scope = this.scope;
let propertyName;
if ( scope === IndexNode.VERTEX ) {
propertyName = builder.getVertexIndex();
} else if ( scope === IndexNode.INSTANCE ) {
propertyName = builder.getInstanceIndex();
} else if ( scope === IndexNode.DRAW ) {
propertyName = builder.getDrawIndex();
} else {
throw new Error( 'THREE.IndexNode: Unknown scope: ' + scope );
}
let output;
if ( builder.shaderStage === 'vertex' || builder.shaderStage === 'compute' ) {
output = propertyName;
} else {
const nodeVarying = varying( this );
output = nodeVarying.build( builder, nodeType );
}
return output;
}
}
IndexNode.VERTEX = 'vertex';
IndexNode.INSTANCE = 'instance';
IndexNode.DRAW = 'draw';
export default IndexNode;
export const vertexIndex = nodeImmutable( IndexNode, IndexNode.VERTEX );
export const instanceIndex = nodeImmutable( IndexNode, IndexNode.INSTANCE );
export const drawIndex = nodeImmutable( IndexNode, IndexNode.DRAW );
addNodeClass( 'IndexNode', IndexNode );