MeshCentral/public/novnc/core/decoders/hextile.js

140 lines
4.7 KiB
JavaScript

/*
* noVNC: HTML5 VNC client
* Copyright (C) 2012 Joel Martin
* Copyright (C) 2018 Samuel Mannehed for Cendio AB
* Copyright (C) 2018 Pierre Ossman for Cendio AB
* Licensed under MPL 2.0 (see LICENSE.txt)
*
* See README.md for usage and integration instructions.
*
*/
import * as Log from '../util/logging.js';
export default class HextileDecoder {
constructor() {
this._tiles = 0;
this._lastsubencoding = 0;
}
decodeRect(x, y, width, height, sock, display, depth) {
if (this._tiles === 0) {
this._tiles_x = Math.ceil(width / 16);
this._tiles_y = Math.ceil(height / 16);
this._total_tiles = this._tiles_x * this._tiles_y;
this._tiles = this._total_tiles;
}
while (this._tiles > 0) {
let bytes = 1;
if (sock.rQwait("HEXTILE", bytes)) {
return false;
}
let rQ = sock.rQ;
let rQi = sock.rQi;
let subencoding = rQ[rQi]; // Peek
if (subencoding > 30) { // Raw
throw new Error("Illegal hextile subencoding (subencoding: " +
subencoding + ")");
}
const curr_tile = this._total_tiles - this._tiles;
const tile_x = curr_tile % this._tiles_x;
const tile_y = Math.floor(curr_tile / this._tiles_x);
const tx = x + tile_x * 16;
const ty = y + tile_y * 16;
const tw = Math.min(16, (x + width) - tx);
const th = Math.min(16, (y + height) - ty);
// Figure out how much we are expecting
if (subencoding & 0x01) { // Raw
bytes += tw * th * 4;
} else {
if (subencoding & 0x02) { // Background
bytes += 4;
}
if (subencoding & 0x04) { // Foreground
bytes += 4;
}
if (subencoding & 0x08) { // AnySubrects
bytes++; // Since we aren't shifting it off
if (sock.rQwait("HEXTILE", bytes)) {
return false;
}
let subrects = rQ[rQi + bytes - 1]; // Peek
if (subencoding & 0x10) { // SubrectsColoured
bytes += subrects * (4 + 2);
} else {
bytes += subrects * 2;
}
}
}
if (sock.rQwait("HEXTILE", bytes)) {
return false;
}
// We know the encoding and have a whole tile
rQi++;
if (subencoding === 0) {
if (this._lastsubencoding & 0x01) {
// Weird: ignore blanks are RAW
Log.Debug(" Ignoring blank after RAW");
} else {
display.fillRect(tx, ty, tw, th, this._background);
}
} else if (subencoding & 0x01) { // Raw
display.blitImage(tx, ty, tw, th, rQ, rQi);
rQi += bytes - 1;
} else {
if (subencoding & 0x02) { // Background
this._background = [rQ[rQi], rQ[rQi + 1], rQ[rQi + 2], rQ[rQi + 3]];
rQi += 4;
}
if (subencoding & 0x04) { // Foreground
this._foreground = [rQ[rQi], rQ[rQi + 1], rQ[rQi + 2], rQ[rQi + 3]];
rQi += 4;
}
display.startTile(tx, ty, tw, th, this._background);
if (subencoding & 0x08) { // AnySubrects
let subrects = rQ[rQi];
rQi++;
for (let s = 0; s < subrects; s++) {
let color;
if (subencoding & 0x10) { // SubrectsColoured
color = [rQ[rQi], rQ[rQi + 1], rQ[rQi + 2], rQ[rQi + 3]];
rQi += 4;
} else {
color = this._foreground;
}
const xy = rQ[rQi];
rQi++;
const sx = (xy >> 4);
const sy = (xy & 0x0f);
const wh = rQ[rQi];
rQi++;
const sw = (wh >> 4) + 1;
const sh = (wh & 0x0f) + 1;
display.subTile(sx, sy, sw, sh, color);
}
}
display.finishTile();
}
sock.rQi = rQi;
this._lastsubencoding = subencoding;
this._tiles--;
}
return true;
}
}