README-DEVELOPER.md

OpenSCAD with 3D glasses

Build notes

These are build notes on compiling OpenSCAD to an AppImage on a raspberry pi 4 running 2020-08-20-raspios-buster-arm64.

Install build dependencies

sudo apt-get upgrade
sudo apt-get install cmake gawk bison flex gettext itstool libcgal-dev libeigen3-dev libfontconfig1-dev libharfbuzz-dev libopengl-dev libglew-dev libopencsg-dev libxml2-dev libboost-all-dev libzip-dev libcairo2-dev lib3mf-dev libqscintilla2-qt5-dev qtmultimedia5-dev imagemagick libqt5gamepad5-dev libhidapi-dev libspnav-dev libdouble-conversion-dev qt5-default

Download sources

git clone http://github.com/koendv/openscad
cd openscad
git submodule update --init

Build openscad

First check all dependencies are installed:

source ./scripts/setenv-unibuild.sh
./scripts/check-dependencies.sh

Check the output of check-dependencies is "OK", then build:

mkdir build
cd build
cmake -DCMAKE_INSTALL_PREFIX=/usr ..
make -j4

Create appimage

The AppImage contains the application, and all shared libraries and files needed to run the application. To create the AppImage, use AppImageKit and linuxqtdeploy.

Build and install AppImageKit:

git clone --recursive https://github.com/AppImage/AppImageKit
mkdir build
cd build/
cmake ..
make
sudo make install

Needed by linuxqtdeploy:

apt-get install patchelf

Get linuxdeployqt:

git clone --recursive https://github.com/probonopd/linuxdeployqt
cd linuxdeployqt

Patch linuxdeployqt:

patch -p1 <<EOD
diff --git a/tools/linuxdeployqt/main.cpp b/tools/linuxdeployqt/main.cpp
index 338a0e2..47f2555 100644
--- a/tools/linuxdeployqt/main.cpp
+++ b/tools/linuxdeployqt/main.cpp
@@ -189,6 +189,7 @@ int main(int argc, char **argv)
     
     // We need to catch those errors at the source of the problem
     // https://github.com/AppImage/appimage.github.io/search?q=GLIBC&unscoped_q=GLIBC&type=Issues
+#if 0
     const char *glcv = gnu_get_libc_version ();
     if(skipGlibcCheck) {
         qInfo() << "WARNING: Not checking glibc on the host system.";
@@ -210,6 +211,7 @@ int main(int argc, char **argv)
             return 1;
         }
     }
+#endif
 
     if (argc < 2 || (firstArgument.startsWith("-"))) {
         qInfo() << "";
EOD

Set path to qmake:

export PATH=/usr/lib/qt5/bin/:$PATH

Build and install linuxdeployqt:

qmake
make
sudo make install

Create OpenSCAD application AppDir:

cd src/openscad/build
export INSTALL_ROOT=$HOME/OpenSCAD-aarch64.AppDir
mkdir $INSTALL_ROOT
make install DESTDIR=$INSTALL_ROOT

Create AppImage:

linuxdeployqt $HOME/OpenSCAD-aarch64.AppDir/usr/share/applications/openscad.desktop -appimage -no-strip 

Test AppImage:

./OpenSCAD-aarch64.AppImage

Run the AppImage on a clean install of the operating system to check all dependencies have been caught.

32-bit version

The 32-bit version for Raspberry Pi OS 2021-03-04-raspios-buster-armhf. It differs in that Qt5, lib3mf and QScintilla have been compiled from source. Configuration command line:

export QT_SELECT=qt5.15.2-opengl
qmake openscad.pro "PREFIX=/usr" "LIB3MF_INCLUDEPATH=/usr/include/Bindings/Cpp"  "LIB3MF_LIBPATH=-l3mf -lzip -lz"

Editing an AppImage

If you wish to edit, add or remove a file in an existing AppImage, there is no need to recompile. Simply extract the file tree from the AppImage, edit, test and re-package:

$ OpenSCAD.AppImage --appimage-extract
$ gedit squashfs-root/usr/share/openscad/color-schemes/render/redcyanglasses.json
$ ./squashfs-root/AppRun
$ appimagetool.AppImage squashfs-root/ OpenSCAD-new.AppImage

Links

• Rendering 3D Anaglyph in OpenGL - Geometry calculations used in file GLView.cc, method GLView::setup3dCamera()
• Calculating Stereo Pairs - How to render and how not to.
• Producing Anaglyphs from Synthetic Images - The coefficients used in file colormap.cc, method ColorMap::anaglyphColor(), are on page 4.
• Pull Request at openscad. Contribute to the source code.

Credits

After a patch by Josef Pavlik