1 files changed, 139 insertions, 0 deletions
diff --git a/core/decoders/hextile.js b/core/decoders/hextile.js
new file mode 100644
index 0000000..91141aa
--- /dev/null
+++ b/core/decoders/hextile.js
@@ -0,0 +1,139 @@
+/*
+ * 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.get_rQ();
+            let rQi = sock.get_rQi();
+
+            let subencoding = rQ[rQi];  // Peek
+            if (subencoding > 30) {  // Raw
+                throw 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.set_rQi(rQi);
+            this._lastsubencoding = subencoding;
+            this._tiles--;
+        }
+
+        return true;
+    }
+}