VMWare mouse support

[learn-more]

VMWare has a custom encoding for the cursor:
https://github.com/rfbproto/rfbproto/blob/master/rfbproto.rst#vmware-cursor-pseudo-encoding

This is something that I am implementing in a tool I'm working on,
would you be interested in me contributing it back?

If that is the case:

• In what form would be preferred?
  • A protocol extension
  • Integrating in rfbclient (re-use HandleCursorPos / GotCursorShape or a new way, the format is slightly different)
• Should there be a testcase for this
• Should there be example code for this? (note, I could not find example code using the int8_t *rcSource, *rcMask; anywhere)

[bk138]

Yes, contribution welcome.

What would speak against re-using HandleCursorPos / GotCursorShape ?

What would a testcase look like?

No example needed.

[learn-more]

Yes, contribution welcome.

What would speak against re-using HandleCursorPos / GotCursorShape ?

What would a testcase look like?

No example needed.

HandleCursorPos can be used as-is,
but the GotCursorShape will need to interpret data differently.

For 'normal' cursors, the rcSource and rcMask contain the data,
where it looks like rcSource contains RGBA data, with the A zeroed out?

VMWare sends RGBA data with the alpha filled out, and no rcMask.

[bk138]

HandleCursorPos can be used as-is, but the GotCursorShape will need to interpret data differently.

• maybe it makes sense to introduce additional callbacks just to be explicit and not hide the fact that info might come
  from different sources.
• or: can client API users distuingish otherwise. I.e. rcMask unset -> rcSource contains rgba ?

[learn-more]

HandleCursorPos can be used as-is, but the GotCursorShape will need to interpret data differently.

* maybe it makes sense to introduce additional callbacks just to be explicit and not hide the fact that info might come
  from different sources.

* or: can client API users distuingish otherwise. I.e. rcMask unset -> rcSource contains rgba ?

Both could work.
Another option would be that the code translates the vmware format to the existing rcMask/rcSource format?

This is really a question of api-design, so I think it makes sense for you to state your preference here. (I have not written the code yet, just made sure that I get valid data in a debugger).

For a testcase, I imagined that a stored message could be handled by the client code, and the resulting cursor be checked but I did not find other code doing stuff like that.

[bk138]

Both could work. Another option would be that the code translates the vmware format to the existing rcMask/rcSource format?

This is really a question of api-design, so I think it makes sense for you to state your preference here. (I have not written the code yet, just made sure that I get valid data in a debugger).

Yes, unfortunately ;-) - Well the API needs a careful redesign later on anyway. Let's say that the callbacks are re-used and:

• the code tries to translate incoming data to what users expext from the existing API
• if that's not feasible, stores data in an additional rfbClient member and theres a Big Fat Warning in the API docs about this

For a testcase, I imagined that a stored message could be handled by the client code, and the resulting cursor be checked but I did not find other code doing stuff like that.

Yeah let's KISS and omit that.

[learn-more]

Thanks for the fast responses,
this is a great incentive to contribute!

[learn-more]

This is less compatible as I hoped.
One of the cursors is fine (cursor type 1).
The other one (cursor type 0) needs custom drawing code:

dst[i] = (dst[i] & and-mask[i]) ^ xor-mask[i];

So that is not translatable to the current image/mask.

When working with vmware, cursor type 1 is used for the arrow,
and cursor type 0 is used for the 'I' cursor in text fields. (It is a black bar, but it is visible over a black line, probably due to the xor operation)

[bk138]

Then it seems you need to go for approach b)

if that's not feasible, stores data in an additional rfbClient member and theres a Big Fat Warning in the API docs about this