[NablaDyn]

Dear potential MegaCads users,

several times I have been asked how to install MegaCads on Ubuntu systems. I know MegaCads always seems a bit bitchy when it comes to that.

Therefore, I decided open a thread containing detailed instructions on how to get MegaCads run properly on Ubuntu. I figured these routines out over hours of trial-and-error approaches and now they seem to function quite perfectly and universally. I successfully run MegaCads on Ubuntu 14.04, 15.10 and 16.10 and use it for mesh generation for OpenFOAM (to use it alongside OpenFOAM see http://www.cfd-online.com/Forums/ope...-megacads.html after installation).

Note: There are surely many other/easier ways to install MegaCads and I don't consider my solution flawless, but it works fine for me. Ever since I managed the installation on Ubuntu 16.10, I have never again encountered any setup related problems concerning installation or use of MegaCads.

[NablaDyn]

The following instructions should apply to any recent 64 bit Ubuntu version.
Note: AFAIK the library 'libXp.so.6', which is required by MegaCads, is not natively available for Ubuntu 16. You therefore may need to build it from source (see below)
Of course, you run all below instructions at your own risk and responsibility...
I subdivided the procedure into several parts to make it easier to follow.

[NablaDyn]

1. Have Ubuntu installed properly and open a terminal.
2. Set up the system's 'locales', MegaCads might otherwise be unable to read grid or geometry files although it seems to work normally.

   $ sudo gedit /etc/defaults/locale

   Change all locales to 'en_US.UTF-8'.
3. Update your system:

   $ sudo apt-get update

   $ sudo apt-get upgrade

4. Check whether C-shell is installed by typing:

   $ csh

   If not, install C-Shell (CSH):

   $ sudo apt-get install csh

   MegaCads doesn't like BASH, so I use a script (shown below) that switches to CSH during my MegaCads sessions automatically.

[NablaDyn]

To embed MegaCads you need to adapt some environment variables in a certain file ('MegaEnvironment') that is shipped with your copy of MegaCads. There is also an installation instruction/client shipped with it, that tries to configure the software more or less automatically but that hasn't worked for me so far ...
Instead, I always use a specific and very strict file structure for storing the executables (feel free to adapt the following locations and names as you please, only be sure to keep consistency):

1. Set up a folder '~/Software/MegaCads' by:

   $ mkdir ~/Software

   $ mkdir  ~/Software/MegaCads

   We will refer to that directory as INSTALLDIR from here on.
2. Extract the MegaCads tarball into the new directory. The new directory should look like figure 1 now.
3. Make sure the file 'MegaEnvironment' is located in the INSTALLDIR. If this is not already the case, do

   $ cp ~/Software/MegaCads/MEGACADS-2.5.2/BINARIES/PC64/MegaEnvironment ~/Software/MegaCads/

   and open it by

   $ gedit ~/Software/MegaCads/MegaEnvironment

4. There's now two environment variables to adapt: '$MEGA_ROOT' and 'MEGA_BIN'. 'MEGA_ROOT' must point to /home/<username>/Software/MegaCads/MEGACADS-2.5.2'. Note, that you must adapt the user name. 'MEGA_BIN' must point to '$MEGA_ROOT/BINARIES/PC64. Accordingly, adapt the 'xrdb -merge' pathes at the end of the file. Everything else is additional stuff or dedicated to other OS and thus, not mandatory. Afterwards, save the file and close it.
5. You may now give it a first shot by switching into C-shell and trying to launch MegaCads from your INSTALLDIR:

   $ csh

   % source MegaEnvironment

   What you get probably looks like figure 2 and tell you that some aliases have been set. The 'mcads2' alias is the one to lauch MegaCads.
6. Lastly, you need to assign sufficient permissions to allow for MegaCads files to be executed, but first, switch back to BASH:

   % bash

7. User level permissions are sufficient:

   $ chmod u+x ~/Software/MegaCads/MEGACADS-2.5.2/BINARIES/PC64/MegaCads

   $ chmod u+x ~/Software/MegaCads/MEGACADS-2.5.2/BINARIES/PC64/MegaBatch

   $ chmod u+x ~/Software/MegaCads/MEGACADS-2.5.2/BINARIES/PC64/MegaEdit

[NablaDyn]

Now, MegaCads itself is set up. But when you try to run it from shell by

$ csh

% source MegaEnvironment

% mcads2

you will pretty likely be informed that certain shared libraries are missing on your system. It clearly depends on your system, whether they are already available or not. So, I will start with the messages (and the corresponding remedies) I always encounter on a fresh Ubuntu setup.

1. libnetcdf.so.4: Install libnetcdf.so.7 (or newer) instead:

   $ sudo apt-get install libnetcdf7

   Softlink the library:

   $ sudo ln -s /usr/lib/x86_64-linux-gnu/libnetcdf.so.7 /usr/lib/libnetcdf.so.4

2. libXm.so.4: Simply install via APT:

   $ sudo apt-get install libxm4

3. libjpeg.so.62: Again:

   $ sudo apt-get install libjpeg62

4. libXp.so.6: This one might be a bit harder to install. On newer Ubuntus (e.g. 16.x) you may need to build it from source:

1. Download the three required package files [libxp_1.0.2-1ubuntu1.dsc] [libxp_1.0.2.orig.tar.gz] [libxp_1.0.2-1ubuntu1.diff.gz] from the ubuntu pages.
2. Place these files in a directory of your choice, enter that directory and run

   $ dpkg-source -x libxp_1.0.2-2.dsc

   This creates a new subdirectory 'libxp...'.
3. Install some utilities necessary for package building:

   $ sudo apt-get install dh-autoreconf quilt x11proto-print-dev xutils-dev

4. Now run

   $ dpkg-buildpackage -uc -us -rfakeroot -b

   to build the library and change the directory by

   $ cd ..

5. You can now conveniently install the library:

   $ sudo dpkg -i libxp-dev_1.0.2-1ubuntu1_amd64.deb libxp6_1.0.2-1ubuntu1_amd64.deb

Well, that should have done the magic. Now try from your INSTALLDIR:

$ csh

% source MegaEnvironment

% mcads2

You should now - with tears of joy welling in your eyes - see something like figure 3.

[Flowkersma]

Hi,

Thank you for the guide! I can now see the main screen. However, when I click file->import->STL-Ascii... nothing happens. No dialogs, no errors, nothing. Do you have suggestions what to do?

When I run MegaCads, I get three warnings which are probably not related to this:

Warning: Cannot convert string "*hel*-m*-r-*-10-*" to type FontStruct
Warning: Cannot convert string "*hel*-b*-r-*-12-*" to type FontStruct
Warning: Cannot convert string "*hel*-m*-r-*-12-*" to type FontStruct

Best,
Mikko

[NablaDyn]

Originally Posted by Flowkersma

Hi,

Thank you for the guide! I can now see the main screen. However, when I click file->import->STL-Ascii... nothing happens. No dialogs, no errors, nothing. Do you have suggestions what to do?

When I run MegaCads, I get three warnings which are probably not related to this:


Best,
Mikko

Hi Mikko,

no these messages are due to the fonts MegaCads wants to use by default and of no importance.
The graphical menu for import/export is not fully functional (as mentioned in the paper). You need to import data via script commands in the SAVE_PROC_FILE. You can use 'read_data' or 'import_geometry' for that. MegaCads comes with HTML help pages (simply view them in your browser). The help pages describe the functionalities and script commands.

HINT: Try to use GUI and text editor simultaneously during mesh creation. This makes it way easier and faster to debug or develop your mesh.

[NablaDyn]

Forgot the most important part ...
To shortcut the launching process, create a 'launch'-file containing the lines (adapt the path):

#!/bin/csh
source  <path_to_MegaEnvironment>
mcads2

Save that file in your INSTALLDIR and make it executable

$ chmod u+x <launch-file>

Additionally, you can now create a desktop-launcher to start MegaCads from the Ubuntu GUI (Unity). Simply put a launcher file (e.g. 'MegaCads.desktop') into /usr/share/applications/.
The launcher needs to look somewhat like this:

#!/usr/bin/env xdg-open
[Desktop Entry]
Version=1.0
Type=Application
Name=MegaCads
Comment=StructuredMeshGenerator
Exec=<path_to_launcher_file>
Icon=<path_to_launcher_icon>
Terminal=false
Categories=Applications

I use this one:

[rnburne]

The particular package I have was downloaded from DLR in Aug, 2015. Attached is some information that hopefully will help........

pic 1 extracted contents
structure of the main folder
pic 2 contents of "TOOLS"
MegaEnvironment file
error message

Each step of the installation process was successful but I'm left with an
error message. Can anyone help?

Ron

[NablaDyn]

Originally Posted by rnburne

The particular package I have was downloaded from DLR in Aug, 2015. Attached is some information that hopefully will help........

pic 1 extracted contents
structure of the main folder
pic 2 contents of "TOOLS"
MegaEnvironment file
error message

Each step of the installation process was successful but I'm left with an
error message. Can anyone help?

Ron

Ron,

it seems you simply forgot to adapt the MegaEnvironment file. Your error is due to the splash screen image MegaCads cannot find because of the not yet defined environment variables. I attached a ME file with info about which lines to change (yellow: edit, red: remove). Additionally, your alias is obviously named 'mcads'. Either change the entry in your ME file (mcads->mcads2) or in the launch script (mcads2->mcads) and it should work...

Hope it helps.

Best regards,

Martin

[Flowkersma]

The directory structure was a bit different for me than in the example. Here are the environment variables that I modified:

setenv MEGA_ROOT /home/mikko/apps/megacads/megacads-2.5.2/MegaCads-2.5.2/
setenv MEGA_BIN $MEGA_ROOT/BINARIES/PC64/
setenv MEGAPIXMAPS   $MEGA_ROOT/MEGACADS/PIXMAP

[NablaDyn]

Originally Posted by Flowkersma

The directory structure was a bit different for me than in the example. Here are the environment variables that I modified:

setenv MEGA_ROOT /home/mikko/apps/megacads/megacads-2.5.2/MegaCads-2.5.2/
setenv MEGA_BIN $MEGA_ROOT/BINARIES/PC64/
setenv MEGAPIXMAPS   $MEGA_ROOT/MEGACADS/PIXMAP

I'm sorry, you are probably right. the structure shown above is the one I always start from. But I think I've accidently mixed it all up a bit back then...
However, the instructions I gave should be consistent as long as you are aware of what your installation's root directory is.

[rnburne]

Originally Posted by NablaDyn

Ron,

it seems you simply forgot to adapt the MegaEnvironment file. Your error is due to the splash screen image MegaCads cannot find because of the not yet defined environment variables. I attached a ME file with info about which lines to change (yellow: edit, red: remove). Additionally, your alias is obviously named 'mcads'. Either change the entry in your ME file (mcads->mcads2) or in the launch script (mcads2->mcads) and it should work...

Hope it helps.

Best regards,

Martin

The MegaEnvr file shown is an unedited version. I had made all the correct
entries......with one small exception. It's now up and running. Thanks.

[NablaDyn]

To make MegaCads run on Ubuntu 20.04 LTS (Focal Fossa), follow the above steps until step "1. libnetcdf.so.4..." in post #5 and make sure to have gdebi installed, for convenience.


Instead of libnetcdf.so.7, you will probably have to install something like libnetcdf.so.15:

sudo apt-get install libnetcdf15

Link as usual:

sudo ln -s /usr/lib/x86_64-linux-gnu/libnetcdf.so.15 /usr/lib/libnetcdf.so.4

Proceed with

sudo apt-get install libxm4

sudo apt-get install libjpeg62

The remaining libraries are not available via apt, but I unearthed them on the web (attached). Install them, e.g., via GUI in the following order (I might have mixed something up...):

1. multiarch...
2. libxp...
3. gcc-base...

Download and install libgfortran from: https://packages.ubuntu.com/bionic-u...tran3/download

Now, execute the "mcads.sh" script as usual. The MegaCads GUI should now pop up. Important: Make sure you are using en-US locales on your system. Otherwise MegaCads may behave weirdly, crash or be unable to import/export data properly.