Add simulated touchpad option for touchscreen devices

[bpsib]

Is your feature request related to a problem? Please describe.

Describe the solution you'd like
Option for a simulated touchpad when used on touchscreen;

Describe alternatives you've considered
Connecting a mouse

Additional context
It would make using noVNC on a touchscreen much easier. It's a complete pain to use on touchscreen devices otherwise.

[CendioOssman]

noVNC already has touch gestures to make it easier to use when using touch screens. Are those not working well for you?

[bpsib]

I rather have the ability to move the mouse by swiping the touchscreen so then I precise control over the mouse cursor. This helps prevent me from clicking the wrong thing by not quite getting my finger in the right place which can be really annoying. Also having no pinch-to-zoom feature makes matters worse. All the VNC mobile apps I have used have the simulated touchpad feature so why not noVNC?

[CendioOssman]

All features take time, not just to implement, but also to maintain. So we would rather not have more stuff than necessary. Which means it is important for us to understand what problems different features solve.

User preference is not irrelevant, but it is not as critical compared to when a new feature solves practical problems.

[pterodyne]

+1 this feature request. thanks for a great project!

[luoluo888]

+1 this feature request. thanks for a great project!!!

[sravyak]

+1 this feature request. thanks for a great project!!!

[kairusds]

+1