implement remote cursor rendering

README.md

@@ -67,7 +67,7 @@ Please tweet [@noVNC](http://www.twitter.com/noVNC) if you do.
 * Supports all modern browsers including mobile (iOS, Android)
 * Supported VNC encodings: raw, copyrect, rre, hextile, tight, tightPNG
 * Supports scaling, clipping and resizing the desktop
-* Local cursor rendering
+* Local or remote cursor rendering
 * Clipboard copy/paste
 * Translations
 * Touch gestures for emulating common mouse actions

core/rfb.js

@@ -285,6 +285,7 @@ export default class RFB extends EventTargetMixin {
         this.focusOnClick = true;
 
         this._viewOnly = false;
+        this._remoteCursor = false;
         this._clipViewport = false;
         this._scaleViewport = false;
         this._resizeSession = false;
@@ -315,6 +316,16 @@ export default class RFB extends EventTargetMixin {
         }
     }
 
+    get remoteCursor() { return this._remoteCursor; }
+    set remoteCursor(remoteCursor) {
+        this._remoteCursor = remoteCursor;
+
+        this._cursor.setVisibility(!remoteCursor);
+        if (this._rfbConnectionState === "connected") {
+            this._sendEncodings();
+        }
+    }
+
     get capabilities() { return this._capabilities; }
 
     get touchButton() { return 0; }
@@ -2072,7 +2083,7 @@ export default class RFB extends EventTargetMixin {
         encs.push(encodings.pseudoEncodingDesktopName);
         encs.push(encodings.pseudoEncodingExtendedClipboard);
 
-        if (this._fbDepth == 24) {
+        if (this._fbDepth == 24 && !this._remoteCursor) {
             encs.push(encodings.pseudoEncodingVMwareCursor);
             encs.push(encodings.pseudoEncodingCursor);
         }

core/util/cursor.js

@@ -10,7 +10,8 @@ const useFallback = !supportsCursorURIs || isTouchDevice;
 
 export default class Cursor {
     constructor() {
-        this._target = null;
+        this._target  = null;
+        this._visible = true;
 
         this._canvas = document.createElement('canvas');
 
@@ -109,6 +110,15 @@ export default class Cursor {
         this._hotSpot.y = 0;
     }
 
+    setVisibility(visible) {
+        this._visible = visible;
+        if (visible) {
+            this._showCursor();
+        } else {
+            this._hideCursor();
+        }
+    }
+
     // Mouse events might be emulated, this allows
     // moving the cursor in such cases
     move(clientX, clientY) {
@@ -201,6 +211,9 @@ export default class Cursor {
         if (!target) {
             return false;
         }
+        if (!this._visible) {
+            return false;
+        }
         // Easy case
         if (target === this._target) {
             return true;

docs/API.md

@@ -21,6 +21,14 @@ protocol stream.
     movement) should be prevented from being sent to the server.
     Disabled by default.
 
+`remoteCursor`
+  - Is a `boolean` indicating if the cursor should be drawn on the server.
+    Usually the cursor is drawn on the client because it provides a more
+    responsive user experience. However in certain situations, for example
+    in conjuction with `viewOnly` it might be desirable to render the 
+    mouse cursor on the server.
+    Disabled by default.
+
 `focusOnClick`
   - Is a `boolean` indicating if keyboard focus should automatically be
     moved to the remote session when a `mousedown` or `touchstart`