three
Version:
JavaScript 3D library
115 lines (73 loc) • 2.61 kB
JavaScript
import TempNode from '../core/TempNode.js';
/**
* This module is part of the TSL core and usually not used in app level code.
* It represents a join operation during the shader generation process.
* For example in can compose/join two single floats into a `vec2` type.
*
* @augments TempNode
*/
class JoinNode extends TempNode {
static get type() {
return 'JoinNode';
}
/**
* Constructs a new join node.
*
* @param {Array<Node>} nodes - An array of nodes that should be joined.
* @param {?string} [nodeType=null] - The node type.
*/
constructor( nodes = [], nodeType = null ) {
super( nodeType );
/**
* An array of nodes that should be joined.
*
* @type {Array<Node>}
*/
this.nodes = nodes;
}
/**
* This method is overwritten since the node type must be inferred from the
* joined data length if not explicitly defined.
*
* @param {NodeBuilder} builder - The current node builder.
* @return {string} The node type.
*/
getNodeType( builder ) {
if ( this.nodeType !== null ) {
return builder.getVectorType( this.nodeType );
}
return builder.getTypeFromLength( this.nodes.reduce( ( count, cur ) => count + builder.getTypeLength( cur.getNodeType( builder ) ), 0 ) );
}
generate( builder, output ) {
const type = this.getNodeType( builder );
const maxLength = builder.getTypeLength( type );
const nodes = this.nodes;
const primitiveType = builder.getComponentType( type );
const snippetValues = [];
let length = 0;
for ( const input of nodes ) {
if ( length >= maxLength ) {
console.error( `THREE.TSL: Length of parameters exceeds maximum length of function '${ type }()' type.` );
break;
}
let inputType = input.getNodeType( builder );
let inputTypeLength = builder.getTypeLength( inputType );
let inputSnippet;
if ( length + inputTypeLength > maxLength ) {
console.error( `THREE.TSL: Length of '${ type }()' data exceeds maximum length of output type.` );
inputTypeLength = maxLength - length;
inputType = builder.getTypeFromLength( inputTypeLength );
}
length += inputTypeLength;
inputSnippet = input.build( builder, inputType );
const inputPrimitiveType = builder.getComponentType( inputType );
if ( inputPrimitiveType !== primitiveType ) {
inputSnippet = builder.format( inputSnippet, inputPrimitiveType, primitiveType );
}
snippetValues.push( inputSnippet );
}
const snippet = `${ builder.getType( type ) }( ${ snippetValues.join( ', ' ) } )`;
return builder.format( snippet, type, output );
}
}
export default JoinNode;