@openhps/core/dist/esm/three/nodes/core/MRTNode.js

Open Hybrid Positioning System - Core component

import OutputStructNode from './OutputStructNode.js';
import { nodeProxy, vec4 } from '../tsl/TSLBase.js';

/**
 * Returns the MRT texture index for the given name.
 *
 * @param {Array<Texture>} textures - The textures of a MRT-configured render target.
 * @param {string} name - The name of the MRT texture which index is requested.
 * @return {number} The texture index.
 */
export function getTextureIndex(textures, name) {
  for (let i = 0; i < textures.length; i++) {
    if (textures[i].name === name) {
      return i;
    }
  }
  return -1;
}

/**
 * This node can be used setup a MRT context for rendering. A typical MRT setup for
 * post-processing is shown below:
 * ```js
 * const mrtNode = mrt( {
 *   output: output,
 *   normal: normalView
 * } ) );
 * ```
 * The MRT output is defined as a dictionary.
 *
 * @augments OutputStructNode
 */
class MRTNode extends OutputStructNode {
  static get type() {
    return 'MRTNode';
  }

  /**
   * Constructs a new output struct node.
   *
   * @param {Object<string, Node>} outputNodes - The MRT outputs.
   */
  constructor(outputNodes) {
    super();

    /**
     * A dictionary representing the MRT outputs. The key
     * is the name of the output, the value the node which produces
     * the output result.
     *
     * @type {Object<string, Node>}
     */
    this.outputNodes = outputNodes;

    /**
     * This flag can be used for type testing.
     *
     * @type {boolean}
     * @readonly
     * @default true
     */
    this.isMRTNode = true;
  }

  /**
   * Returns `true` if the MRT node has an output with the given name.
   *
   * @param {string} name - The name of the output.
   * @return {NodeBuilder} Whether the MRT node has an output for the given name or not.
   */
  has(name) {
    return this.outputNodes[name] !== undefined;
  }

  /**
   * Returns the output node for the given name.
   *
   * @param {string} name - The name of the output.
   * @return {Node} The output node.
   */
  get(name) {
    return this.outputNodes[name];
  }

  /**
   * Merges the outputs of the given MRT node with the outputs of this node.
   *
   * @param {MRTNode} mrtNode - The MRT to merge.
   * @return {MRTNode} A new MRT node with merged outputs..
   */
  merge(mrtNode) {
    const outputs = {
      ...this.outputNodes,
      ...mrtNode.outputNodes
    };
    return mrt(outputs);
  }
  setup(builder) {
    const outputNodes = this.outputNodes;
    const mrt = builder.renderer.getRenderTarget();
    const members = [];
    const textures = mrt.textures;
    for (const name in outputNodes) {
      const index = getTextureIndex(textures, name);
      members[index] = vec4(outputNodes[name]);
    }
    this.members = members;
    return super.setup(builder);
  }
}
export default MRTNode;

/**
 * TSL function for creating a MRT node.
 *
 * @tsl
 * @function
 * @param {Object<string, Node>} outputNodes - The MRT outputs.
 * @returns {MRTNode}
 */
export const mrt = /*@__PURE__*/nodeProxy(MRTNode);