@novnc/novnc
Version:
An HTML5 VNC client
192 lines (190 loc) • 7.87 kB
JavaScript
"use strict";
Object.defineProperty(exports, "__esModule", {
value: true
});
exports["default"] = void 0;
var _inflator = _interopRequireDefault(require("../inflator.js"));
function _interopRequireDefault(e) { return e && e.__esModule ? e : { "default": e }; }
function _typeof(o) { "@babel/helpers - typeof"; return _typeof = "function" == typeof Symbol && "symbol" == typeof Symbol.iterator ? function (o) { return typeof o; } : function (o) { return o && "function" == typeof Symbol && o.constructor === Symbol && o !== Symbol.prototype ? "symbol" : typeof o; }, _typeof(o); }
function _classCallCheck(a, n) { if (!(a instanceof n)) throw new TypeError("Cannot call a class as a function"); }
function _defineProperties(e, r) { for (var t = 0; t < r.length; t++) { var o = r[t]; o.enumerable = o.enumerable || !1, o.configurable = !0, "value" in o && (o.writable = !0), Object.defineProperty(e, _toPropertyKey(o.key), o); } }
function _createClass(e, r, t) { return r && _defineProperties(e.prototype, r), t && _defineProperties(e, t), Object.defineProperty(e, "prototype", { writable: !1 }), e; }
function _toPropertyKey(t) { var i = _toPrimitive(t, "string"); return "symbol" == _typeof(i) ? i : i + ""; }
function _toPrimitive(t, r) { if ("object" != _typeof(t) || !t) return t; var e = t[Symbol.toPrimitive]; if (void 0 !== e) { var i = e.call(t, r || "default"); if ("object" != _typeof(i)) return i; throw new TypeError("@@toPrimitive must return a primitive value."); } return ("string" === r ? String : Number)(t); } /*
* noVNC: HTML5 VNC client
* Copyright (C) 2021 The noVNC authors
* Licensed under MPL 2.0 (see LICENSE.txt)
*
* See README.md for usage and integration instructions.
*
*/
var ZRLE_TILE_WIDTH = 64;
var ZRLE_TILE_HEIGHT = 64;
var ZRLEDecoder = exports["default"] = /*#__PURE__*/function () {
function ZRLEDecoder() {
_classCallCheck(this, ZRLEDecoder);
this._length = 0;
this._inflator = new _inflator["default"]();
this._pixelBuffer = new Uint8Array(ZRLE_TILE_WIDTH * ZRLE_TILE_HEIGHT * 4);
this._tileBuffer = new Uint8Array(ZRLE_TILE_WIDTH * ZRLE_TILE_HEIGHT * 4);
}
return _createClass(ZRLEDecoder, [{
key: "decodeRect",
value: function decodeRect(x, y, width, height, sock, display, depth) {
if (this._length === 0) {
if (sock.rQwait("ZLib data length", 4)) {
return false;
}
this._length = sock.rQshift32();
}
if (sock.rQwait("Zlib data", this._length)) {
return false;
}
var data = sock.rQshiftBytes(this._length, false);
this._inflator.setInput(data);
for (var ty = y; ty < y + height; ty += ZRLE_TILE_HEIGHT) {
var th = Math.min(ZRLE_TILE_HEIGHT, y + height - ty);
for (var tx = x; tx < x + width; tx += ZRLE_TILE_WIDTH) {
var tw = Math.min(ZRLE_TILE_WIDTH, x + width - tx);
var tileSize = tw * th;
var subencoding = this._inflator.inflate(1)[0];
if (subencoding === 0) {
// raw data
var _data = this._readPixels(tileSize);
display.blitImage(tx, ty, tw, th, _data, 0, false);
} else if (subencoding === 1) {
// solid
var background = this._readPixels(1);
display.fillRect(tx, ty, tw, th, [background[0], background[1], background[2]]);
} else if (subencoding >= 2 && subencoding <= 16) {
var _data2 = this._decodePaletteTile(subencoding, tileSize, tw, th);
display.blitImage(tx, ty, tw, th, _data2, 0, false);
} else if (subencoding === 128) {
var _data3 = this._decodeRLETile(tileSize);
display.blitImage(tx, ty, tw, th, _data3, 0, false);
} else if (subencoding >= 130 && subencoding <= 255) {
var _data4 = this._decodeRLEPaletteTile(subencoding - 128, tileSize);
display.blitImage(tx, ty, tw, th, _data4, 0, false);
} else {
throw new Error('Unknown subencoding: ' + subencoding);
}
}
}
this._length = 0;
return true;
}
}, {
key: "_getBitsPerPixelInPalette",
value: function _getBitsPerPixelInPalette(paletteSize) {
if (paletteSize <= 2) {
return 1;
} else if (paletteSize <= 4) {
return 2;
} else if (paletteSize <= 16) {
return 4;
}
}
}, {
key: "_readPixels",
value: function _readPixels(pixels) {
var data = this._pixelBuffer;
var buffer = this._inflator.inflate(3 * pixels);
for (var i = 0, j = 0; i < pixels * 4; i += 4, j += 3) {
data[i] = buffer[j];
data[i + 1] = buffer[j + 1];
data[i + 2] = buffer[j + 2];
data[i + 3] = 255; // Add the Alpha
}
return data;
}
}, {
key: "_decodePaletteTile",
value: function _decodePaletteTile(paletteSize, tileSize, tilew, tileh) {
var data = this._tileBuffer;
var palette = this._readPixels(paletteSize);
var bitsPerPixel = this._getBitsPerPixelInPalette(paletteSize);
var mask = (1 << bitsPerPixel) - 1;
var offset = 0;
var encoded = this._inflator.inflate(1)[0];
for (var y = 0; y < tileh; y++) {
var shift = 8 - bitsPerPixel;
for (var x = 0; x < tilew; x++) {
if (shift < 0) {
shift = 8 - bitsPerPixel;
encoded = this._inflator.inflate(1)[0];
}
var indexInPalette = encoded >> shift & mask;
data[offset] = palette[indexInPalette * 4];
data[offset + 1] = palette[indexInPalette * 4 + 1];
data[offset + 2] = palette[indexInPalette * 4 + 2];
data[offset + 3] = palette[indexInPalette * 4 + 3];
offset += 4;
shift -= bitsPerPixel;
}
if (shift < 8 - bitsPerPixel && y < tileh - 1) {
encoded = this._inflator.inflate(1)[0];
}
}
return data;
}
}, {
key: "_decodeRLETile",
value: function _decodeRLETile(tileSize) {
var data = this._tileBuffer;
var i = 0;
while (i < tileSize) {
var pixel = this._readPixels(1);
var length = this._readRLELength();
for (var j = 0; j < length; j++) {
data[i * 4] = pixel[0];
data[i * 4 + 1] = pixel[1];
data[i * 4 + 2] = pixel[2];
data[i * 4 + 3] = pixel[3];
i++;
}
}
return data;
}
}, {
key: "_decodeRLEPaletteTile",
value: function _decodeRLEPaletteTile(paletteSize, tileSize) {
var data = this._tileBuffer;
// palette
var palette = this._readPixels(paletteSize);
var offset = 0;
while (offset < tileSize) {
var indexInPalette = this._inflator.inflate(1)[0];
var length = 1;
if (indexInPalette >= 128) {
indexInPalette -= 128;
length = this._readRLELength();
}
if (indexInPalette > paletteSize) {
throw new Error('Too big index in palette: ' + indexInPalette + ', palette size: ' + paletteSize);
}
if (offset + length > tileSize) {
throw new Error('Too big rle length in palette mode: ' + length + ', allowed length is: ' + (tileSize - offset));
}
for (var j = 0; j < length; j++) {
data[offset * 4] = palette[indexInPalette * 4];
data[offset * 4 + 1] = palette[indexInPalette * 4 + 1];
data[offset * 4 + 2] = palette[indexInPalette * 4 + 2];
data[offset * 4 + 3] = palette[indexInPalette * 4 + 3];
offset++;
}
}
return data;
}
}, {
key: "_readRLELength",
value: function _readRLELength() {
var length = 0;
var current = 0;
do {
current = this._inflator.inflate(1)[0];
length += current;
} while (current === 255);
return length + 1;
}
}]);
}();