src/int32x4array.js

/*
  Copyright (C) 2013

  This software is provided 'as-is', without any express or implied
  warranty.  In no event will the authors be held liable for any damages
  arising from the use of this software.

  Permission is granted to anyone to use this software for any purpose,
  including commercial applications, and to alter it and redistribute it
  freely, subject to the following restrictions:

  1. The origin of this software must not be misrepresented; you must not
     claim that you wrote the original software. If you use this software
     in a product, an acknowledgment in the product documentation would be
     appreciated but is not required.
  2. Altered source versions must be plainly marked as such, and must not be
     misrepresented as being the original software.
  3. This notice may not be removed or altered from any source distribution.
*/

"use strict";


function Int32x4Array(a, b, c) {

  function isNumber(o) {
      return typeof o == "number" || (typeof o == "object" && o.constructor === Number);
  }

  function isTypedArray(o) {
    return (o instanceof Int8Array) ||
           (o instanceof Uint8Array) ||
           (o instanceof Uint8ClampedArray) ||
           (o instanceof Int16Array) ||
           (o instanceof Uint16Array) ||
           (o instanceof Int32Array) ||
           (o instanceof Uint32Array) ||
           (o instanceof Float32Array) ||
           (o instanceof Float64Array) ||
           (o instanceof Int32x4Array) ||
           (o instanceof Float32x4Array);
  }

  function isArrayBuffer(o) {
    return (o instanceof ArrayBuffer);
  }

  if (isNumber(a)) {
    this.storage_ = new Int32Array(a*4);
    this.length_ = a;
    this.byteOffset_ = 0;
    return;
  } else if (isTypedArray(a)) {
    if (!(a instanceof Int32x4Array)) {
      throw "Copying typed array of non-Int32x4Array is unimplemented.";
    }
    this.storage_ = new Int32Array(a.length * 4);
    this.length_ = a.length;
    this.byteOffset_ = 0;
    // Copy integers.
    for (var i = 0; i < a.length*4; i++) {
      this.storage_[i] = a.storage_[i];
    }
  } else if (isArrayBuffer(a)) {
    if ((b != undefined) && (b % Int32x4Array.BYTES_PER_ELEMENT) != 0) {
      throw "byteOffset must be a multiple of 16.";
    }
    if (c != undefined) {
      c *= 4;
      this.storage_ = new Int32Array(a, b, c);
    }
    else {
      // Note: new Int32Array(a, b) is NOT equivalent to new Float32Array(a, b, undefined)
      this.storage_ = new Int32Array(a, b);
    }
    this.length_ = this.storage_.length / 4;
    this.byteOffset_ = b != undefined ? b : 0;
  } else {
    throw "Unknown type of first argument.";
  }
}

Object.defineProperty(Int32x4Array.prototype, 'length',
  { get: function() { return this.length_; }
});

Object.defineProperty(Int32x4Array.prototype, 'byteLength',
  { get: function() { return this.length_ * Int32x4Array.BYTES_PER_ELEMENT; }
});

Object.defineProperty(Int32x4Array, 'BYTES_PER_ELEMENT',
  { get: function() { return 16; }
});

Object.defineProperty(Int32x4Array.prototype, 'BYTES_PER_ELEMENT',
  { get: function() { return 16; }
});

Object.defineProperty(Int32x4Array.prototype, 'byteOffset',
  { get: function() { return this.byteOffset_; }
});

Object.defineProperty(Int32x4Array.prototype, 'buffer',
  { get: function() { return this.storage_.buffer; }
});

Int32x4Array.prototype.getAt = function(i) {
  if (i < 0) {
    throw "Index must be >= 0.";
  }
  if (i >= this.length) {
    throw "Index out of bounds.";
  }
  var x = this.storage_[i*4+0];
  var y = this.storage_[i*4+1];
  var z = this.storage_[i*4+2];
  var w = this.storage_[i*4+3];
  return SIMD.int32x4(x, y, z, w);
}

Int32x4Array.prototype.setAt = function(i, v) {
  if (i < 0) {
    throw "Index must be >= 0.";
  }
  if (i >= this.length) {
    throw "Index out of bounds.";
  }
  if (!(v instanceof SIMD.int32x4)) {
    throw "Value is not a int32x4.";
  }
  this.storage_[i*4+0] = v.x;
  this.storage_[i*4+1] = v.y;
  this.storage_[i*4+2] = v.z;
  this.storage_[i*4+3] = v.w;
}