lippicv missing ubuntu 16.10

[wotanii]

#### abstract

Following the build/installation guide ends in an error "/us/bin/ld: cannot find -lippicv".

#### reproduction

OS: ubuntu 16.10, gnome3,

# follow the installation-guide on https://github.com/panda3d/panda3d

sudo apt-get install build-essential pkg-config python-dev libpng-dev libjpeg-dev libtiff-dev zlib1g-dev libssl-dev libx11-dev libgl1-mesa-dev libxrandr-dev libxxf86dga-dev libxcursor-dev bison flex libfreetype6-dev libvorbis-dev libeigen3-dev libopenal-dev libode-dev libbullet-dev nvidia-cg-toolkit libgtk2.0-dev

python2.7 makepanda/makepanda.py --everything --installer --no-egl --no-gles --no-gles2

expected result: successful build

actual result: error "/us/bin/ld: cannot find -lippicv"

#### possible reason

an old version of opencv required lippicv, even though it didn't. Maybe something like that is also the case here?

#### workaround/solution

none so far.
I tried installing openCV, but it merely triggered a rebuild. It did not fix the issue.

[rdb (rdb)]

It's very odd that you had the pkg-config files for OpenCV without having the OpenCV development package installed. This is likely an issue with the OpenCV packages.

However, there really isn't much purpose in building Panda with OpenCV support now that we support Video4Linux for webcam capture. To people who run into this issue, I would suggest building with --no-opencv to be sure. In the future, I will probably simply disable it by default to avoid issues like this.

[wotanii (wotanii)]

correction: openCV DID NOT FIX the issue. It merely triggered a long rebuild.

I still get the same error. The full build-output is in the attachment.

[rdb (rdb)]

I suggest you build with --no-opencv since there is nothing to gain by building with OpenCV nowadays on Linux.

I will either update the readme instructions to include this flag, or disable it by default in makepanda.

I also recommend you build with --threads=N where N is the number of cores you have to spare. This will greatly speed up the build.

[wotanii (wotanii)]

I had more missing dependencies (even with the --no-opencv flag). I solved them by copying them to panda3d/built/lib as well. After installing the resulting deb-file, I was able run a couple of examples, so I assume everything worked out.

In total I needed the following files:

* libippicv.a
* libpng16.so
* libpng16.so.16
* libpng16.so.16.22.0

I don't know if it affected the process, but I did not clear the build-directory before adding files and adding the opencv-flag.

[rdb (rdb)]

Latest master version now disables OpenCV if ffmpeg is also present. Compile instructions also mention --no-opencv flag.