Executive summary: There is no cursor in viewer using TurboVNC viewer 2.1 running on a Debian 8 machine to connect to an Ubuntu 12.04 (yes, I know it's old, but can't upgrade now) server running TigerVNC x0vncserver 1.7.0.
I've come to this combination because TurboVNC does not have a x0vncserver (which I need) and TigerVNC viewer does not support scaling (which is nice to have). Using TigerVNC at both sides works fine, but there's no scaling. Both TurboVNC and TigerVNC viewers with x11vnc server work fine, but this is waaay slower.
I've tried all viewer and server options (i.e. local/server cursor, scaling on/off, etc.) to no avail. Can't say whether the problem is at the viewer or server side, so I'm opening an issue on both in the hope that this otherwise fantastic combination becomes useable.
I'm afraid x0vncserver doesn't support a mouse cursor in any way. So you need to use a client that supports a fallback cursor display. There is commonly an option to show a dot when there is no cursor.
The option to display a dot when there is no cursor is better than nothing, but barely. That dot is so small that it is hard to follow. An option to specify the cursor shape, or even an option to specify an arrow cursor would help greatly.
A workaround is to use the vnc.so module. I just tested it under RHEL7.3 (tigervnc-server-module-1.3.1-9.el7.x86_64), it shows me the server's mouse cursor.