Adding CUP button and CUP mode.

[williamlemus]

https://bugs.launchpad.net/mixxx/+bug/1535468

The CUP mode has been added. It works the following way:

• Press, pause at the cue point
• release, play

It is available as a Cue mode, or as a button that can be learned.

[sblaisot]

indentation problem between the first two lines and the next two lines.

[daschuer]

// If stopped, press to set as cue point.

I am not sure if that is desired. Do you have a reference for this feature?

EDIT: I have found some, so the set behaviour is correct.

[sblaisot]

Thanks fo this PR.

Did you sign the mixxx contributor agreement ? https://docs.google.com/a/mixxx.org/spreadsheet/viewform?formkey=dEpYN2NkVEFnWWQzbkFfM0ZYYUZ5X2c6MQ

Please also update the mixxxcontrols wiki page when this PR will be merged.

[daschuer]

Thank you for this Pull Request.

Unfortunately this branch does not merge cleanly with our master branch. It is a good practice to keep your own master branch equal with the upstream master branch of mixxxdj/mixxx.

This can be done from the command line like that:

# copy your changes into a feature branch 
git checkout master
git checkout -b CUP_feature

# adding mixxxdj/mixxx as upstream, if not already done:
git remote add upstream https://github.com/mixxxdj/mixxx.git

# set your master to upstream master 
git fetch upstream
git checkout master
git reset upstream/master --hard

# rebase your changes onto your new master
git checkout CUP_feature
git rebase master
# this will conflict. meld is a nice tool to resolve these conflicts side by side 
sudo apt-get install meld 

# resolve conflicts:
git mergetool
# add changed files 
git add <changed files list>
git rebase --continue  

# publish your changes
git push 

# now you have to issue a new pull request here on GitHub for your new branch.

[daschuer]

IMHO this the CUP button is a button of its own, not a cue button in a cue mode.
How about:

addDeckControl("cue_play", tr("CUP (Cue Play)),
                          tr("Goto cue point and play after release"), cueMenu);

[daschuer]

http://www.reloop.com/reloop-digital-jockey-2-master-edition#
in Tutorial Video 9, they say that CUP also sets the cue point when paused.

[daschuer]

Not sure, but here it is nothing about setting a cue point with CUP
http://www.reloop.com/media/custom/upload/Reloop-Reloop_Beatmix2_VirtualDJ8_Operation_Guide.pdf

[daschuer]

OK, after searching the web some more, I think your implementation with cue set feature is just right.

[williamlemus]

I will make a new pull request(rebased from the upstream master branch) with the following changes:

• Change tab to spaces
• Reword the addDeckControl to:

addDeckControl("cue_play", tr("CUP (Cue Play)),
                          tr("Goto cue point and play after release"), cueMenu);

• Remove the quantization:

            // If quantize is enabled, jump to the cue point since it's not
            // necessarily where we currently are
            if (m_pQuantizeEnabled->get() > 0.0) {
                lock.unlock();  // prevent deadlock.
                // Enginebuffer will quantize more exactly than we can.
                seekAbs(m_pCuePoint->get());