three
Version:
JavaScript 3D library
128 lines (99 loc) • 1.91 kB
JavaScript
import Binding from './Binding.js';
import { getFloatLength } from './BufferUtils.js';
/**
* Represents a buffer binding type.
*
* @private
* @abstract
* @augments Binding
*/
class Buffer extends Binding {
/**
* Constructs a new buffer.
*
* @param {string} name - The buffer's name.
* @param {TypedArray} [buffer=null] - The buffer.
*/
constructor( name, buffer = null ) {
super( name );
/**
* This flag can be used for type testing.
*
* @type {boolean}
* @readonly
* @default true
*/
this.isBuffer = true;
/**
* The bytes per element.
*
* @type {number}
*/
this.bytesPerElement = Float32Array.BYTES_PER_ELEMENT;
/**
* A reference to the internal buffer.
*
* @private
* @type {TypedArray}
*/
this._buffer = buffer;
/**
* An array of update ranges.
*
* @private
* @type {Array<{start: number, count: number}>}
*/
this._updateRanges = [];
}
/**
* The array of update ranges.
*
* @type {Array<{start: number, count: number}>}
*/
get updateRanges() {
return this._updateRanges;
}
/**
* Adds an update range.
*
* @param {number} start - The start index.
* @param {number} count - The number of elements.
*/
addUpdateRange( start, count ) {
this.updateRanges.push( { start, count } );
}
/**
* Clears all update ranges.
*/
clearUpdateRanges() {
this.updateRanges.length = 0;
}
/**
* The buffer's byte length.
*
* @type {number}
* @readonly
*/
get byteLength() {
return getFloatLength( this._buffer.byteLength );
}
/**
* A reference to the internal buffer.
*
* @type {Float32Array}
* @readonly
*/
get buffer() {
return this._buffer;
}
/**
* Updates the binding.
*
* @return {boolean} Whether the buffer has been updated and must be
* uploaded to the GPU.
*/
update() {
return true;
}
}
export default Buffer;