| 1 | /* |
| 2 | * noVNC: HTML5 VNC client |
| 3 | * Copyright (C) 2019 The noVNC Authors |
| 4 | * Licensed under MPL 2.0 (see LICENSE.txt) |
| 5 | * |
| 6 | * See README.md for usage and integration instructions. |
| 7 | * |
| 8 | */ |
| 9 | |
| 10 | import * as Log from '../util/logging.js'; |
| 11 | |
| 12 | export default class HextileDecoder { |
| 13 | constructor() { |
| 14 | this._tiles = 0; |
| 15 | this._lastsubencoding = 0; |
| 16 | this._tileBuffer = new Uint8Array(16 * 16 * 4); |
| 17 | } |
| 18 | |
| 19 | decodeRect(x, y, width, height, sock, display, depth) { |
| 20 | if (this._tiles === 0) { |
| 21 | this._tilesX = Math.ceil(width / 16); |
| 22 | this._tilesY = Math.ceil(height / 16); |
| 23 | this._totalTiles = this._tilesX * this._tilesY; |
| 24 | this._tiles = this._totalTiles; |
| 25 | } |
| 26 | |
| 27 | while (this._tiles > 0) { |
| 28 | let bytes = 1; |
| 29 | |
| 30 | if (sock.rQwait("HEXTILE", bytes)) { |
| 31 | return false; |
| 32 | } |
| 33 | |
| 34 | let subencoding = sock.rQpeek8(); |
| 35 | if (subencoding > 30) { // Raw |
| 36 | throw new Error("Illegal hextile subencoding (subencoding: " + |
| 37 | subencoding + ")"); |
| 38 | } |
| 39 | |
| 40 | const currTile = this._totalTiles - this._tiles; |
| 41 | const tileX = currTile % this._tilesX; |
| 42 | const tileY = Math.floor(currTile / this._tilesX); |
| 43 | const tx = x + tileX * 16; |
| 44 | const ty = y + tileY * 16; |
| 45 | const tw = Math.min(16, (x + width) - tx); |
| 46 | const th = Math.min(16, (y + height) - ty); |
| 47 | |
| 48 | // Figure out how much we are expecting |
| 49 | if (subencoding & 0x01) { // Raw |
| 50 | bytes += tw * th * 4; |
| 51 | } else { |
| 52 | if (subencoding & 0x02) { // Background |
| 53 | bytes += 4; |
| 54 | } |
| 55 | if (subencoding & 0x04) { // Foreground |
| 56 | bytes += 4; |
| 57 | } |
| 58 | if (subencoding & 0x08) { // AnySubrects |
| 59 | bytes++; // Since we aren't shifting it off |
| 60 | |
| 61 | if (sock.rQwait("HEXTILE", bytes)) { |
| 62 | return false; |
| 63 | } |
| 64 | |
| 65 | let subrects = sock.rQpeekBytes(bytes).at(-1); |
| 66 | if (subencoding & 0x10) { // SubrectsColoured |
| 67 | bytes += subrects * (4 + 2); |
| 68 | } else { |
| 69 | bytes += subrects * 2; |
| 70 | } |
| 71 | } |
| 72 | } |
| 73 | |
| 74 | if (sock.rQwait("HEXTILE", bytes)) { |
| 75 | return false; |
| 76 | } |
| 77 | |
| 78 | // We know the encoding and have a whole tile |
| 79 | sock.rQshift8(); |
| 80 | if (subencoding === 0) { |
| 81 | if (this._lastsubencoding & 0x01) { |
| 82 | // Weird: ignore blanks are RAW |
| 83 | Log.Debug(" Ignoring blank after RAW"); |
| 84 | } else { |
| 85 | display.fillRect(tx, ty, tw, th, this._background); |
| 86 | } |
| 87 | } else if (subencoding & 0x01) { // Raw |
| 88 | let pixels = tw * th; |
| 89 | let data = sock.rQshiftBytes(pixels * 4, false); |
| 90 | // Max sure the image is fully opaque |
| 91 | for (let i = 0;i < pixels;i++) { |
| 92 | data[i * 4 + 3] = 255; |
| 93 | } |
| 94 | display.blitImage(tx, ty, tw, th, data, 0); |
| 95 | } else { |
| 96 | if (subencoding & 0x02) { // Background |
| 97 | this._background = new Uint8Array(sock.rQshiftBytes(4)); |
| 98 | } |
| 99 | if (subencoding & 0x04) { // Foreground |
| 100 | this._foreground = new Uint8Array(sock.rQshiftBytes(4)); |
| 101 | } |
| 102 | |
| 103 | this._startTile(tx, ty, tw, th, this._background); |
| 104 | if (subencoding & 0x08) { // AnySubrects |
| 105 | let subrects = sock.rQshift8(); |
| 106 | |
| 107 | for (let s = 0; s < subrects; s++) { |
| 108 | let color; |
| 109 | if (subencoding & 0x10) { // SubrectsColoured |
| 110 | color = sock.rQshiftBytes(4); |
| 111 | } else { |
| 112 | color = this._foreground; |
| 113 | } |
| 114 | const xy = sock.rQshift8(); |
| 115 | const sx = (xy >> 4); |
| 116 | const sy = (xy & 0x0f); |
| 117 | |
| 118 | const wh = sock.rQshift8(); |
| 119 | const sw = (wh >> 4) + 1; |
| 120 | const sh = (wh & 0x0f) + 1; |
| 121 | |
| 122 | this._subTile(sx, sy, sw, sh, color); |
| 123 | } |
| 124 | } |
| 125 | this._finishTile(display); |
| 126 | } |
| 127 | this._lastsubencoding = subencoding; |
| 128 | this._tiles--; |
| 129 | } |
| 130 | |
| 131 | return true; |
| 132 | } |
| 133 | |
| 134 | // start updating a tile |
| 135 | _startTile(x, y, width, height, color) { |
| 136 | this._tileX = x; |
| 137 | this._tileY = y; |
| 138 | this._tileW = width; |
| 139 | this._tileH = height; |
| 140 | |
| 141 | const red = color[0]; |
| 142 | const green = color[1]; |
| 143 | const blue = color[2]; |
| 144 | |
| 145 | const data = this._tileBuffer; |
| 146 | for (let i = 0; i < width * height * 4; i += 4) { |
| 147 | data[i] = red; |
| 148 | data[i + 1] = green; |
| 149 | data[i + 2] = blue; |
| 150 | data[i + 3] = 255; |
| 151 | } |
| 152 | } |
| 153 | |
| 154 | // update sub-rectangle of the current tile |
| 155 | _subTile(x, y, w, h, color) { |
| 156 | const red = color[0]; |
| 157 | const green = color[1]; |
| 158 | const blue = color[2]; |
| 159 | const xend = x + w; |
| 160 | const yend = y + h; |
| 161 | |
| 162 | const data = this._tileBuffer; |
| 163 | const width = this._tileW; |
| 164 | for (let j = y; j < yend; j++) { |
| 165 | for (let i = x; i < xend; i++) { |
| 166 | const p = (i + (j * width)) * 4; |
| 167 | data[p] = red; |
| 168 | data[p + 1] = green; |
| 169 | data[p + 2] = blue; |
| 170 | data[p + 3] = 255; |
| 171 | } |
| 172 | } |
| 173 | } |
| 174 | |
| 175 | // draw the current tile to the screen |
| 176 | _finishTile(display) { |
| 177 | display.blitImage(this._tileX, this._tileY, |
| 178 | this._tileW, this._tileH, |
| 179 | this._tileBuffer, 0); |
| 180 | } |
| 181 | } |