44 KiB
🌊 S P A C E 🪐 🅱 O X 💫
/\ +-------------------------------------------------------+
____/ \____ /| Open source game framework licensed to freely use, |
\ / / | copy, and modify - created for dank.game |
+--\ ^__^ /--+ | |
| ~/ \~ | | Download at https://open.shampoo.ooo/shampoo/spacebox |
| ~~~~~~~~~~~~ | +-------------------------------------------------------+
| SPACE ~~~~~ | /
| ~~~~~~~ BOX |/
+--------------+
SPACE🪐BOX is a framework that makes creating cross-platform games and other interactive applications easier and faster by providing an added layer of abstraction between SDL + OpenGL and the project.
It was created for 💫dank.game💫. The games Cakefoot, B.U.D.D.I., Gunkiss, and Pepy use SPACE🪐BOX.
Requirements
External
- SDL2 (currently tested against 2.26.3)
- SDL2-image
- SDL2-ttf
- SDL2-mixer
- OpenGL or OpenGL ES (currently tested against OpenGL 3.2 and OpenGL ES 2.0)
- C++ compiler that supports C++17
SDL2, SDL2-image, SDL2-ttf, SDL2-mixer
Use a package manager like apt
if possible.
apt install libsdl2-dev libsdl2-image-dev libsdl2-mixer-dev libsdl2-ttf-dev
Otherwise, visit the repositories for each and follow instructions for installation.
- https://github.com/libsdl-org/SDL
- https://github.com/libsdl-org/SDL_image
- https://github.com/libsdl-org/SDL_ttf
- https://github.com/libsdl-org/SDL_mixer
OpenGL
Install OpenGL or OpenGL ES according to your platform and link to it during compilation. In most cases, it is already installed.
Internal
The rest of the required libraries are included in the repository.
- GLM
- GLEW
- nlohmann::json
- SDL2-gfx
- GIF-H
- SuperXBR
- CLI11
- Catch2
There are example build scripts in the Cakefoot project, the test folder, and the demo folder that demonstrate how to build them.
Builds
🚧🚧🚧
SPACE🪐BOX is expected to be built along with the project implementing it since currently only the source is available.
The details of the build process are still mostly undocumented aside from the notes below, which are not guaranteed to be kept up to date with the latest version of SPACE🪐BOX and are not comprehensive guides.
It is recommended to try building the Cakefoot project and using its Makefile as a basis for any new project. After looking at that Makefile, the following notes may be useful in creating another project.
Linux
A simple up-to-date Makefile is available at src/test/Makefile, and there is also a more complex one in the [Cakefoot repository][].
Copy the Makefile from Cakefoot, which demonstrates how to compile SPACE🪐BOX and link to required libraries, adapt it to fit a new project, and build a Linux executable with GNU make.
Linux Distributable
➡ See this related Stack Overflow thread
There are few techniques that can be used to increase compatibility among Linux versions for the resulting binary.
Checking dependencies
Use readelf
to see which libraries a binary uses and what the extra search path is
$ readelf -d build/x86_64/Cakefoot-linux.x86_64
Dynamic section at offset 0x1a2c10 contains 36 entries:
Tag Type Name/Value
0x0000000000000001 (NEEDED) Shared library: [libSDL2-2.0.so.0]
0x0000000000000001 (NEEDED) Shared library: [libGL.so.1]
0x0000000000000001 (NEEDED) Shared library: [libGLESv2.so.2]
0x0000000000000001 (NEEDED) Shared library: [libSDL2_image-2.0.so.0]
0x0000000000000001 (NEEDED) Shared library: [libSDL2_ttf-2.0.so.0]
0x0000000000000001 (NEEDED) Shared library: [libSDL2_mixer-2.0.so.0]
0x0000000000000001 (NEEDED) Shared library: [libstdc++.so.6]
0x0000000000000001 (NEEDED) Shared library: [libm.so.6]
0x0000000000000001 (NEEDED) Shared library: [libgcc_s.so.1]
0x0000000000000001 (NEEDED) Shared library: [libc.so.6]
...
Use objdump
to see which symbols a binary uses. In this case ios_base
is needed from GLIBCXX_3.4.32
(an older version of GLIBCXX couldn't be used for the ios_base_library_init
symbol during compilation).
$ objdump -x build/x64/Cakefoot-linux.x64 | grep GLIBCXX_3.4.32 | c++filt
0x0297f842 0x00 23 GLIBCXX_3.4.32
0000000000000000 F *UND* 0000000000000000 std::ios_base_library_init()@GLIBCXX_3.4.32
Static flags
Adding -static-libgcc
and -static-libstdc++
to the linker flags will remove the dependencies on libstdc++
and libgcc_s
.
Older compiler
Using an older version of GCC to compile can lower the version of some symbols.
Packaging shared libraries
The rpath
property can be used to add a local library search path to the linker, and any libraries to package with the distributable can be added to the local path. For example, this is how SDL is packaged with Cakefoot.
This flag is used to add a relative library lookup path
-Wl,-rpath $(X64_BUILD_LIB_DIR)
This block is used to copy the SDL libraries into the local library folder
cp $$(ldd $(X64_BUILD_DIR)/$@ | grep libSDL2-2.0 | cut -d" " -f3) \
$$(ldd $(X64_BUILD_DIR)/$@ | grep libSDL2_image | cut -d" " -f3) \
$$(ldd $(X64_BUILD_DIR)/$@ | grep libSDL2_ttf | cut -d" " -f3) \
$$(ldd $(X64_BUILD_DIR)/$@ | grep libSDL2_mixer | cut -d" " -f3) ${basename $@}/$(X64_BUILD_LIB_DIR)
Virtualization using Docker
Docker can be used to compile for a target platform with a desired baseline compatibility profile, for example, Ubuntu 16.04.
apt install docker.io
Make sure your user has sudo permissions to use /usr/bin/docker
by editing either /etc/sudoers/
or a file in /etc/sudoers.d/
. Then pull the Ubuntu 16.04 image.
sudo docker pull ubuntu:16.04
To be continued... 🚧
Emscripten
Creating a browser build with Emscripten and its built-in version of SDL has worked well on a few projects. The general process is to create a separate make target that uses Emscripten's C++ to WebAssembly compiler. See the browser webcam demo for an example.
Expected Warnings
The browser console will report an error Uncaught unwind
. This is expected and is related to how Emscripten launches the program.
If exception support is enabled using the -fexception
flag, the browser console will report an error.
emscripten_set_main_loop_timing: Cannot set timing mode for main loop since a main loop does not exist!
Call emscripten_set_main_loop first to set one up.
This warning can be safely ignored. See the Github issue for more information.
Raspberry Pi
Raspberry Pi builds, like Android and Emscripten, require using OpenGL ES. The build process is similar to standard desktop Linux.
GLEW is not available for OpenGL ES, so GLES headers are included directly from the expected system directories.
The flag -DGLEW_NO_GLU
may also be necessary since there may not be a glu.h
file on Raspberry Pi installations. This flag can also just be used by default because GLU is deprecated.
SDL
SDL should be built with --enable-video-kmsdrm
. This will require the installation of external packages. OpenGL ES will also need to be installed.
sudo apt install libgbm-dev libdrm-dev libegl-dev libgles2-mesa-dev
Otherwise, SDL can be installed in the same way described above.
KMS
If using the Raspberry Pi without X-windows, SDL will run in KMS mode. The config for the latest versions of the Raspberry Pi OS Lite should be setup correctly by default, and the installation of SDL from source should enable KMS by default if the necessary packages above have been installed. However, it is good to verify that /boot/firmware/config.txt
is setup correctly and that SDL is built with KMS video output enabled.
To verify /boot/firmware/config.txt
, make sure the line dtoverlay=vc4-kms-v3d
is included in the file. This activates KMS mode for the console instead of either Fake KMS or the older framebuffer modes.
Build the testgles2.c
SDL test
In the SDL source downloaded in the previous step, there is a test/testgles2.c
program that draws a rotating cube using GLES. This can be used to verify that the SDL installation is working on the Pi.
cd [SDL_source]/test/
gcc $(sdl-config --cflags --libs) -LSDL_test -o testgles
./testgles
Raspberry Pi Model 3B+
This model only supports up to Open GL ES 2.0.
Raspberry Pi Model 4
This model supports up to Open GL ES 3.2.
External demos
Try these non-SPACEBOX demos for verifying the Raspberry Pi OpenGL ES setup with KMS.
Android
The fill_screen demo has a working example of how to build for Android. It may be worthwhile to read the SDL wiki Android page and SDL docs Android README and compile an SDL example for Linux before doing a SPACEBOX Android build. The source distributions for SDL, SDL image, SDL ttf, and SDL mixer, and the Android SDK are required.
After building the demo, see the following for further information on using SDL on Android.
- SDL wiki
- SDL Android README
- In the SDL source package,
SDL_android.h
and the Android section ofSDL_system.h
Building an SDL example for Linux
-
Install Java packages
apt install openjdk-17-jdk ant
-
Make a folder for Android to store the SDK, NDK, emulator, tools, etc.
mkdir -p ~/local/Android/
-
Download Android command line tools to that folder, extract them, and install an NDK (the gradle tool included with SDL defaults to NDK 21.4.7075529). Note that the gradle tool may download Android tools, but this step seems to be necessary for signing the license, which gets created in
licenses
$ cd ~/local/Android/ $ unzip commandlinetools-linux-8512546_latest.zip $ cmdline-tools/bin/sdkmanager --sdk_root=$HOME/local/Android/ "ndk;21.4.7075529"
-
Download and extract SDL source
$ wget "https://github.com/libsdl-org/SDL/releases/download/release-2.24.0/SDL2-2.24.0.tar.gz" $ tar -xf SDL2-2.24.0.tar.gz $ cd SDL2-2.24.0/
-
Copy
android-project/
to another folder, symlink the SDL source,$ cp -r android-project org.my.testgles $ cd org.my.testgles/app/jni $ ln -s ../../.. SDL
-
Edit the line with
YourSourcehere.c
inorg.my.testgles/app/jni/src/Android.mk
to point to an SDL example$ cd src/ && sed -i s#YourSourceHere.c#../SDL/test/testgles.c# Android.mk
-
Build with
gradlew
in the root of the project, specifying where to find the Android folder$ ANDROID_SDK_ROOT=$HOME/local/Android ./gradlew build
-
The APK should be output to
app/build/outputs/apk/debug/app-debug.apk
. It can be uploaded to the phone for testing or run on an emulator. To create an emulator, use the Android SDK's tools. For example, to create an Android emulator for API level 31 (Android 12.0) with ABI x86_64.# Install a version of command line tools with support for later versions of Java $ cmdline-tools/bin/sdkmanager --sdk_root=$HOME/local/Android "cmdline-tools;latest" # Install a system image $ cmdline-tools/bin/sdkmanager --sdk_root=$HOME/local/Android "system-images;android-31;default;x86_64" # Create emulator $ cmdline-tools/latest/bin/avdmanager create avd -n android_31_x86_64 -k "system-images;android-31;default;x86_64" # Launch in the background $ ~/local/Android/tools/emulator -avd android_31_x86_64 & # Install the APK to the running emulator $ ~/local/Android/platform-tools/adb -e install -r app/build/outputs/apk/debug/app-debug.apk # Start the log viewer $ ~/local/Android/platform-tools/adb [-s device_name] logcat
fill_screen demo
The fill_screen demo has a Makefile that should work for building for Android if the paths in the file are adjusted to match the project. Edit the Makefile and run make build/android/[org.my.app]
. If that isn't working, see below for notes on how the build was originally done manually.
Custom assets
Assets can be copied to app/src/main/assets
. The box demo has an example of how to include custom assets like config JSON and shaders.
Creating the fill_screen Android build
These steps were taken to build the fill_screen demo for Android. The Android SDK is assumed to be installed as explained above in the SDL test example. The instructions are based on SDL 2.24.0. There is also a Makefile target that scripts this process in [demo/fill_screen/Makefile][]
.
-
Copy the included Android project in the SDL source into the root of the fill_screen project folder.
$ cp -r path/to/SDL2-2.24.0/android-project [fill_screen root]/ooo.shampoo.fill_screen $ cd [fill_screen root]/ooo.shampoo.fill_screen
-
Edit the application ID
$ sed -i s/org.libsdl.app/ooo.shampoo.fill_screen/ app/build.gradle app/src/main/AndroidManifest.xml
-
Enable C++ STL
$ sed -i "s/^#.*\(APP_STL\)/\1/" app/jni/Application.mk
-
Enable C++ 17 features and exceptions
$ echo "APP_CPPFLAGS := -std=c++17 -fexceptions -frtti" >> app/jni/Application.mk
-
Modify rules to allow OpenGL ES 3.0 (necessary for example for using GL_RGBA8)
$ sed -i -e 's/^LOCAL_LDLIBS.*/& -lGLESv3/' app/jni/src/Android.mk $ sed -i 's/0x0002/0x0003/' app/src/main/AndroidManifest.xml $ sed -i 's/\(minSdkVersion\).*16/\1 18/' app/build.gradle $ sed -i 's/\(android\)-16/\1-18/' app/build.gradle app/jni/Application.mk
-
std::filesystem
is only available in NDK 22+, so install NDK version 22 and set the project to use it$ ~/local/Android/cmdline-tools/bin/sdkmanager --sdk_root=$HOME/local/Android --install "ndk;22.1.7171670" $ sed -i '11i\ ndkVersion "22.1.7171670"' app/build.gradle
-
Link to SDL source packages (versions other than the listed ones may work)
$ ln -s path/to/SDL2-2.24.0 app/jni/SDL $ ln -s path/to/SDL2_image-2.6.2 app/jni/SDL2_image $ ln -s path/to/SDL2_mixer-2.6.2 app/jni/SDL2_mixer $ ln -s path/to/SDL2_ttf-2.20.1 app/jni/SDL2_ttf
-
Add SDL packages as libraries in the Makefile
$ sed -i 's/^LOCAL_SHARED_LIBRARIES.*/& SDL2_image SDL2_mixer SDL2_ttf/' app/jni/src/Android.mk
-
Add SPACEBOX lib/ and src/ to include search path. In this command, the paths are relative to the path of Android.mk and based on the location of fill_screen as included in the SPACEBOX repository, but they can be edited to other paths if necessary.
$ sed -i 's#^LOCAL_C_INCLUDES.*#& $(LOCAL_PATH)/../../../../../../lib $(LOCAL_PATH)/../../../../../../src#' \ app/jni/src/Android.mk
-
Add SPACEBOX source files from lib/ src/ and source files for fill_screen
$ sed -i 's#YourSourceHere.c#$(LOCAL_PATH)/../../../../fill_screen.cpp#' app/jni/src/Android.mk $ sed -i 's#^LOCAL_SRC_FILES.*#& $(wildcard $(LOCAL_PATH)/../../../../../../src/*.cpp)#' app/jni/src/Android.mk $ sed -i 's#^LOCAL_SRC_FILES.*#& $(wildcard $(LOCAL_PATH)/../../../../../../lib/sdl2-gfx/*.c)#' app/jni/src/Android.mk
-
Create a file at
app/src/main/java/ooo/shampoo/fill_screen/FillScreen.java
with the following contentspackage ooo.shampoo.fill_screen; import org.libsdl.app.SDLActivity; public class FillScreen extends SDLActivity { protected String getMainFunction() { return "main"; } }
-
Edit the manifest to point to that class
$ sed -i 's/\(name=\)"SDLActivity"/\1"FillScreen"/' app/src/main/AndroidManifest.xml
-
Run gradle
$ ANDROID_SDK_ROOT=$HOME/local/Android ./gradlew build
Screen rotation
Note that SDL_WINDOW_RESIZABLE
is required for screen rotation to work
Cross compilation considerations
std::filesystem::exists
will not work with files stored in the Android APK
Windows
Windows builds are made with MinGW. The box demo contains a make target for building a Windows 32-bit executable from a Linux system. To build from Windows itself, the make target will have to be modified. The SDL MinGW releases and MinGW itself must be downloaded separately.
Download SDL's MinGW libraries from the SDL releases page. Download the libraries for SDL image, SDL mixer, and SDL ttf as well.
mkdir SDL2-mingw
cd SDL2-mingw
wget "https://github.com/libsdl-org/SDL/releases/download/release-2.24.2/SDL2-devel-2.24.2-mingw.zip"
unzip SDL2-devel-2.24.2-mingw.zip
wget "https://github.com/libsdl-org/SDL_image/releases/download/prerelease-2.5.2/SDL2_image-devel-2.5.2-mingw.tar.gz"
tar -xf SDL2_image-devel-2.5.2-mingw.tar.gz
wget "https://github.com/libsdl-org/SDL_ttf/releases/download/release-2.0.15/SDL2_ttf-devel-2.0.15-mingw.tar.gz"
tar -xf SDL2_ttf-devel-2.0.15-mingw.tar.gz
wget "https://github.com/libsdl-org/SDL_mixer/releases/download/prerelease-2.5.2/SDL2_mixer-devel-2.5.2-mingw.tar.gz"
tar -xf SDL2_mixer-devel-2.5.2-mingw.tar.gz
Install MinGW. The simplest way to install is through the package manager. On Debian the command is
apt install mingw-w64
Add -DGLEW_STATIC
to compile the GLEW library into a [SPACE BOX] project using MinGW.
Add -static-libgcc
and -static-libstdc++
to the linker flags to compile GCC and C++ STD runtime DLLs into the executable instead of distributing the DLL file with the executable.
Add -mwindows
to the linker flags to prevent Windows from opening a console window in the background when launching the game.
See the Windows section of demo/box/Makefile
for a complete list of necessary flags and build process.
Cross compilation considerations
std::filesystem::path::c_str
returns aconst wchar_t*
instead ofconst char*
. To make a platform generic call, convert the path to a string, then usestd::filesystem::path::string::c_str
instead.- In order to use
std::thread
with MinGW, you must use the POSIX version of the compiler, for examplex86_64-w64-mingw32-g++-posix
and add-lpthread
to the linker flags.
MacOS
To fully support macOS, both Intel x86_64-macos
and ARM aarch64-macos
architecture versions must be compiled.
Make sure the version of macOS on the build host system is supported by the version of SDL being used. There is information in the documentation in the SDL source at SDL2-2.X.X/docs/README-macos.md
. If necessary, upgrade the macOS operating system, using the official Apple support links, or downgrade SDL by downloading a lower version.
To begin compiling for macOS, clone the cross compilation toolkit osxcross tool
git clone https://github.com/tpoechtrager/osxcross
Install necessary packages
apt install clang make libssl-dev lzma-dev libxml2-dev xz-utils bzip2 cpio zlib1g-dev
Download the Xcode XIP archive to the root of the repository and use the toolkit to generate the SDK as a TAR archive
./tools/gen_sdk_package_pbzx.sh <xcode>.xip
Move the SDK TAR archive into tarballs/
and run the build script at the root of the repository
./build.sh
Add the bin/
directory to PATH
PATH=$PATH:/media/gdrive/osxcross/target/bin/
Get the target value from osxcross-conf
. In this case it's darwin20.4
$ target/bin/osxcross-conf
export OSXCROSS_VERSION=1.5
export OSXCROSS_OSX_VERSION_MIN=10.9
export OSXCROSS_TARGET=darwin20.4
...
Update references to OpenGL for macOS if necessary. See this thread about alternatives to OpenGL on Mac for future concerns about OpenGL on macOS. This is currently handled in SPACE🪐BOX with the following pre-processor directive.
#if defined(__MACOS__)
#define GL_SILENCE_DEPRECATION
#include <OpenGL/gl3.h>
#endif
Get the SDL Framework DMG releases so SDL can be included in the project. The following is a build target for creating a signed and notarized app bundle and DMG of Cakefoot for macOS. There are some important parts to be expanded on in a future update, including linking to frameworks, using an rpath, compiling with a deployment target and universal architecture, and creating an app bundle along with its Info.plist. The signing and notarization process is explained in the next section.
MACOS_CROSS_ROOT = /media/gdrive/osxcross
MACOS_CROSS_FW = $(MACOS_CROSS_ROOT)/local/Frameworks
MACOS_CFLAGS = -Wall -Wextra -O3 -c -I$(SB_LIB_DIR) -I$(SB_SRC_DIR) -DGLEW_STATIC -DGLEW_NO_GLU -F$(MACOS_CROSS_FW) \
-I$(MACOS_CROSS_FW)/SDL2.framework/Headers -I$(MACOS_CROSS_FW)/SDL2_image.framework/Headers \
-I$(MACOS_CROSS_FW)/SDL2_ttf.framework/Headers -I$(MACOS_CROSS_FW)/SDL2_mixer.framework/Headers -D__MACOS__ -D__APPLE__
MACOS_CXXFLAGS = $(CFLAGS) --std=c++17
MACOS_LFLAGS = -Wl,-rpath,@executable_path/../Frameworks -pthread -F$(MACOS_CROSS_FW) -framework SDL2 \
-framework SDL2_image -framework SDL2_ttf -framework SDL2_mixer -framework OpenGL
MACOS_OBJ = $(addprefix $(MACOS_BUILD_DIR)/, glew.o SDL2_rotozoom.o SDL2_gfxPrimitives.o $(SB_O_FILES) $(SRC_O_FILES))
MACOS_BUNDLE = $(MACOS_BUILD_DIR)/dmg/$@
MACOS_BUNDLE_CONTENTS = $(MACOS_BUILD_DIR)/dmg/$@/Contents
MACOS_CROSS_BIN = $(MACOS_CROSS_ROOT)/target/bin
MACOS_CERTIFICATE = local/Cakefoot_MacOS_DeveloperID_Application.pem
MACOS_RCODESIGN = ~/ext/software/apple-codesign-0.27.0/rcodesign
Cakefoot.app : CC = MACOSX_DEPLOYMENT_TARGET=11.3 PATH=$(PATH):$(MACOS_CROSS_BIN) o64-clang -arch arm64 -arch x86_64
Cakefoot.app : CXX = MACOSX_DEPLOYMENT_TARGET=11.3 PATH=$(PATH):$(MACOS_CROSS_BIN) o64-clang++ -arch arm64 -arch x86_64
Cakefoot.app : CFLAGS = $(MACOS_CFLAGS)
Cakefoot.app : CXXFLAGS = $(MACOS_CXXFLAGS)
Cakefoot.app : LFLAGS = $(MACOS_LFLAGS)
Cakefoot.app : $(MACOS_OBJ)
mkdir -p $(MACOS_BUNDLE_CONTENTS)/MacOS $(MACOS_BUNDLE_CONTENTS)/Frameworks $(MACOS_BUNDLE_CONTENTS)/Resources
cp src/Info.plist $(MACOS_BUNDLE_CONTENTS)
cp -r $(MACOS_CROSS_FW)/SDL2*.framework $(MACOS_BUNDLE_CONTENTS)/Frameworks
$(CXX) $^ $(LFLAGS) -o $(MACOS_BUNDLE_CONTENTS)/MacOS/$(basename $@)
rsync -arRL resource/ src/shaders/ config.json $(MACOS_BUNDLE_CONTENTS)/Resources
$(MACOS_RCODESIGN) sign --for-notarization --code-signature-flags runtime --pem-file $(MACOS_CERTIFICATE) \
$(MACOS_BUNDLE)
notarize :
$(MACOS_RCODESIGN) notary-submit --api-key-file local/Cakefoot_App_Store_Connect_API_key.json --staple \
$(MACOS_BUILD_DIR)/dmg/Cakefoot.app
cd $(MACOS_BUILD_DIR) && genisoimage -V Cakefoot -D -R -apple -no-pad -hide-rr-moved -o Cakefoot.dmg dmg && cd -
Signing a DMG
Download Apple Codesign Tools
wget https://github.com/indygreg/apple-platform-rs/releases/download/apple-codesign/0.27.0/apple-codesign-0.27.0-x86_64-unknown-linux-musl.tar.gz
Generate a Certificate Signing Request
openssl genrsa -out local/Cakefoot_CSR_key.pem 2048
rcodesign generate-certificate-signing-request --pem-file local/Cakefoot_CSR_key.pem --csr-pem-file \
local/Cakefoot_Certificate_Signing_Request.pem
Or generate certificates using Xcode on MacOS
Exchange the Certificate Signing Request (CSR) for a Code Signing Certificate (CSC)
- Go to https://developer.apple.com/account/resources/certificates/add (you must be logged into Apple’s website)
- Select the certificate flavor you want to issue.
- Click Continue to advance to the next form.
- Select the G2 Sub-CA (Xcode 11.4.1 or later) Profile Type (we support it).
- Choose the file containing your CSR.
- Click Continue.
- If all goes according to plan, you should see a page saying Download Your Certificate.
- Click the Download button.
- Save the certificate somewhere. (Saved below as
Cakefoot_MacOS_DeveloperID_Application.crt
)
View the certificate
openssl x509 -in local/Cakefoot_MacOS_DeveloperID_Application.cer -text -noout
Combine the certificate with the private key into a single PEM file
openssl x509 -inform der -in Cakefoot_MacOS_DeveloperID_Application.cer -out Cakefoot_MacOS_DeveloperID_Application.pem
cat local/Cakefoot_CSR_key.pm >> Cakefoot_MacOS_DeveloperID_Application.pem
Sign the Application Bundle (in-place)
rcodesign sign --for-notarization --code-signature-flags runtime \
--pem-file local/Cakefoot_MacOS_DeveloperID_Application.pem Cakefoot.app
To view the signature info of a signed app on MacOS
codesign --display --verbose=4 /Volumes/Cakefoot/Cakefoot.app
To notarize, generate a team API key with Developer access role. Download it to a path, for example Cakefoot_App_Store_Connect_API_key_33UBLVSW4Y.p8
. Use the Issuer ID
and KEY ID
from the Apple Developer site combined with the downloaded file to create a JSON document. Submit a request for notarization, wait for the response, and automatically staple. See Review Guidelines for details on what Apple checks for during notarization.
rcodesign notary-submit --api-key-file local/Cakefoot_App_Store_Connect_API_key.json --staple build/macos/dmg/Cakefoot.app
Check the app bundle on MacOS
codesign --verify --verbose Cakefoot.app
spctl -a -t exec -vv Cakefoot.app
Debugging notes
-
Make sure there are no absolute paths other than system libraries in the binary by verifying with
otool -l /path/to/binary
. In the case of Cakefoot, an unnecessary absoluterpath
was erroneously being added in a previous version of the build script. See this thread for more info. -
Make sure the ZIP archive of the app bundle is zipped with
--symlinks
to prevent creating extra copies of the contents of the linked directories in the framework folders. In addition to taking up more space, removing the symlinks will cause the app to fail against thespctl
test and Gatekeeper. -
Gatekeeper seems to require that
Info.plist
has theCFBundlePackageType
key set toAPPL
. -
An application downloaded from the internet can be flagged as quarantined regardless of whether it is certified and notarized. The quarantine flag is controlled by the application which downloads the file, and it seems like web browsers on MacOS are configured to quarantine files. When an application is quarantined, it is moved into the
/private/var/
directory. When Cakefoot is directly downloaded from the web in DMG format, it is flagged to be quarantined, and an unknown reason related to quarantining cause the game to crash. The current less than ideal solution is to move Cakefoot out of the DMG into another folder, for example/System/Applications
or/Users/[user]/Desktop
. -
Possibly useful entitlements that would be added to a plist file
Cakefoot.entitlements
com.apple.security.app-sandbox (set to false) com.apple.security.cs.allow-unsigned-executable-memory com.apple.security.cs.disable-executable-page-protection com.apple.security.cs.disable-library-validation com.apple.security.cs.allow-dyld-environment-variables (needed by Steam API)
Demos
As the project matures, these demos are intended to be transitioned into an automated testing suite, but they are not currently guaranteed to be up to date with the latest version of SPACE🪐BOX. In fact, they don't even indicate which version of SPACE🪐BOX they're compatible with since versioning was only added recently.
The demo/
folder contains programs that demonstrate and test the capabilities of the framework. In order to compile each, you should edit the definitions in the Makefile.
Fill screen
This is intended to be a bare minimum test of the framework which loads the framework and fills the screen with a new color each frame. It currently builds to Linux and Android.
Box
Test OpenGL context by drawing a textured, rotating cube. It currently builds to Linux, Android, and web browsers.
Browser webcam
An example for using a C++ program to display a webcam stream in the browser using Emscripten to translate the code from C++ to WebAssembly. Get the frame pixel data from a canvas element, read it into a SPACEBOX object, write the pixel data to an OpenGL texture, and use Emscripten to display the video.
Squircle
Map an image from a rectangle to a circle or from a circle to a rectangle using a shader program. Based on a blog post about elliptical grid mapping equations.
OpenCV camera
Get camera input using the OpenCV library on Linux or Android.
Testing
The Catch2 framework is used for testing SPACE🪐BOX. It comes included with the repository. Catch2 can be used to write custom tests for SPACE🪐BOX projects as well.
The tests and test data are kept in the src/test/
folder. There is a Makefile
that includes build targets for supported platforms. If the necessary prerequisites are installed for the target platform, the Makefile
can be used to build a test program. For example, if the SDL and OpenGL prerequisites are installed, and the target is Linux, the build can be created by running the following in the test folder.
make SPACEBOX-linux_test.x64
The test program will be output to build/x64/SPACEBOX-linux_text.x64
. Run the program, and it should create a window and quickly exit with all tests passing.
$ build/x64/SPACEBOX-linux_test.x64
Randomness seeded to: 68735375
===============================================================================
All tests passed (1 assertion in 1 test case)
A text file with the results will be created in the working directory. This can be useful for reading the results without running in a terminal, for example on Windows or MacOS. A JSON file with the test results will also be created automatically in the working directory. This can be useful for loading the results into an external program like a CI system.
Per-project tests
If using more than one file to define tests, define the following macro in only one of the files before including catch_amalgamated.hpp
.
#define CATCH_CONFIG_MAIN
To use your own main function, which is what the SPACE🪐BOX tests do, use the -DCATCH_AMALGAMATED_CUSTOM_MAIN
preprocessor flag when building the tests.
Then it becomes possible to add command line configuration directly to the test code.
Catch::Session sess;
const char *args[11] = {"program", "-s", "-d", "yes", "--use-colour", "no", "-r",
"compact", "-o", "test_result1", "Test1"};
int res = sess.run(11, args);
Catch2 provides listener classes which can listen for events, for example test run begin and end, and run custom code
#include <catch2/catch_amalgamated.hpp>
class testRunListener : public Catch::EventListenerBase {
public:
using Catch::EventListenerBase::EventListenerBase;
void testRunStarting(Catch::TestRunInfo const&) override {
lib_foo_init();
}
};
Other libraries
These are other libraries that have been used in projects that use this framework but aren't required by the framework
OpenCV
Download a source package and follow the specific instructions for each platform.
Linux
Create a build directory, then configure and make. This example uses a custom installation path ~/local/opencv
:
$ mkdir build_linux/ && cd build_linux/
$ cmake -DCMAKE_INSTALL_PREFIX=$HOME/local/opencv ..
$ make && make install
The core
, imgproc
, videoio
, and highgui
modules can then be linked to by adding the following to the linker flags:
-L$(HOME)/local/opencv/lib -Wl,-rpath,$(HOME)/local/opencv/lib -lopencv_videoio -lopencv_core -lopencv_highgui \
-lopencv_imgproc
The specific modules needed may vary depending on the project. See detailed instructions for building OpenCV on Linux for more advanced installation. There are also contributed modules available, which can be downloaded separately and compiled with the core modules. For example, this command builds all the modules in ../../opencv_contrib-4.x/modules
, except python3
, along with the core modules.
$ cmake -D CMAKE_INSTALL_PREFIX=$HOME/local/opencv -D OPENCV_EXTRA_MODULES_PATH="../../opencv_contrib-4.x/modules" -D \
BUILD_opencv_python3=OFF ..
Emscripten
To build the WASM libraries necessary to include OpenCV in an Emscripten build of a SPACEBOX project, set up the Emscripten environment and run OpenCV's build_js.py
script with the WASM output option. Note that OpenCV's cv::VideoCapture
object will not be available in the libraries built this way because OpenCV emulates that object in its JS implementation.
$ source [EMSDK_PATH]/emsdk_env.sh
$ python3 [OPENCV_PATH]/platforms/js/build_js.py --emscripten_dir [EMSCRIPTEN_PATH] build_wasm --build_wasm
There is a detailed explanation of this process at [https://docs.opencv.org/4.6.0/d4/da1/tutorial_js_setup.html]. And useful information for getting around the absence of cv::VideoCapture
at [https://docs.opencv.org/4.6.0/dd/d00/tutorial_js_video_display.html]. Check out a minimal example of using OpenCV with C++ and Emscripten at [https://github.com/mpizenberg/emscripten-opencv]. There is also information on how to build the contributed modules as WASM libraries in the first link.
At the time of writing this, the contributed module for barcode scanning needs -DBUILD_PROTOBUF=ON
added to the build_js.py
script and needs js
added to its list of wrapper languages in its CMakeLists.txt
file to compile successfully.
To link to the WASM libraries, add the *.a
files from the build directory to Emscripten's linker flags. Add both lib/*.a
and 3rdparty/lib/*.a
. For GNU Make, this might look like the following.
$(wildcard $(addprefix $(WASM_BUILD_DIR)/lib/,*.a)) $(wildcard $(addprefix $(WASM_BUILD_DIR)/3rdparty/lib/,*.a))
Android
Follow the steps at Building an SDL example for Linux up to the NDK installation steps, using 24.0.8215888 as the NDK version. This version or higher is necessary for using cv::VideoCapture.
$ ~/local/Android/cmdline-tools/bin/sdkmanager --sdk_root=$HOME/local/Android --install "ndk;24.0.8215888"
To build the OpenCV Android SDK, including shared object files, one for each Android ABI, run the build_sdk.py
script packaged with the OpenCV source.
$ cd [opencv_source]
$ python3 platforms/android/build_sdk.py --sdk_path ~/local/Android/ --ndk_path ~/local/Android/ndk/24.0.8215888/ \
--extra_modules_path ../opencv_contrib-4.7.0-subset/ --shared --no_samples_build \
--config ndk-18-api-level-24.config.py build_android/
$ ls -R build_android/OpenCV-android-sdk/sdk/native/libs/
build_android/OpenCV-android-sdk/sdk/native/libs/:
arm64-v8a armeabi-v7a x86 x86_64
build_android/OpenCV-android-sdk/sdk/native/libs/arm64-v8a:
libopencv_world.so libtbb.so
build_android/OpenCV-android-sdk/sdk/native/libs/armeabi-v7a:
libopencv_world.so libtbb.so
build_android/OpenCV-android-sdk/sdk/native/libs/x86:
libopencv_world.so libtbb.so
build_android/OpenCV-android-sdk/sdk/native/libs/x86_64:
libopencv_world.so libtbb.so
This SDK can be included in an Android NDK project. See the camera demo for an example of how to add it to a SPACEBOX project build.
Full example
This builds the local, WASM, and Android libraries by downloading OpenCV 4.7.0 and the contributed modules source packages. See Gunkiss for an example of using these libraries in a project with multiple target platforms.
$ wget https://github.com/opencv/opencv/archive/4.7.0.zip
$ unzip 4.7.0.zip
$ tar -xf opencv_contrib-4.7.0.tar.gz
$ mkdir opencv_contrib-4.7.0-subset
$ cp -r opencv_contrib-4.7.0/modules/barcode/ opencv_contrib-4.7.0-subset/
$ rm -rf ~/local/opencv/
$ cd opencv-4.7.0/
$ mkdir build_linux
$ cd build_linux/
$ cmake -D CMAKE_INSTALL_PREFIX=$HOME/local/opencv -D OPENCV_EXTRA_MODULES_PATH="../../opencv_contrib-4.7.0-subset/" ..
...
-- OpenCV modules:
-- To be built: barcode calib3d core dnn features2d flann gapi highgui imgcodecs imgproc java ml objdetect
photo python3 stitching ts video videoio
...
$ make -j3 && make install
$ cd ..
$ source ~/ext/software/emsdk/emsdk_env.sh
$ python3 platforms/js/build_js.py --cmake_option="-DOPENCV_EXTRA_MODULES_PATH=../../opencv_contrib-4.7.0-subset/" \
--emscripten_dir ~/ext/software/emsdk/upstream/emscripten build_wasm_contrib --build_wasm
$ python3 platforms/android/build_sdk.py --sdk_path ~/local/Android/ --ndk_path ~/local/Android/ndk/22.1.7171670/ \
--extra_modules_path ../opencv_contrib-4.7.0-subset/ --shared --no_samples_build build_android/
curl
Linux
Install from the package manager
sudo apt install libcurl4-openssl-dev
Emscripten
Use Emscripten's Fetch API instead of curl
Android
There are instructions on how to build for Android in the curl documentation. There is also a project libcurl-android that facilitates the build process.
$ git clone --recursive https://github.com/ibaoger/libcurl-android
Add x86
to the APP_ABI
parameter in build_for_android.sh
. Then run the build script.
$ NDK_ROOT=/path/to/NDK ./build_for_android.sh
The libraries should be written the jni/build
folder. The folder libs/x86-64
should actually be named libs/x86_64
, so rename it.
$ mv jni/build/zlib/x86-64 jni/build/zlib/x86_64
$ mv jni/build/curl/x86-64 jni/build/curl/x86_64
$ mv jni/build/openssl/x86-64/ jni/build/openssl/x86_64
See how the OpenCV libraries are included in an Android NDK project in the camera demo for an example of how to use pre-built shared libraries.
ZBar
Linux
Download from http://zbar.sourceforge.net/download.html and configure to only use image processing features (requires the imagemagickwand library, available from, for example apt get libmagickwand-dev
) and choose your installation directory:
./configure --without-gtk --without-python --without-qt --without-xshm --without-xv --without-jpeg \
--disable-video --prefix=$HOME/local/zbar
make
make && make install
Emscripten
To build a WASM library that can be used to build an Emscripten version of a SPACEBOX project, set up the Emscripten environment and configure using emconfigure
with the same disable flags as above.
$ source emsdk_env.sh
$ emconfigure ./configure --without-gtk --without-python --without-qt --without-xshm --without-xv --without-jpeg \
--disable-video
$ emmake make
$ find . -iname *.a
./zbar/.libs/libzbar.a
There is a detailed tutorial on using Zbar with WebAssembly at https://barkeywolf.consulting/posts/barcode-scanner-webassembly/
External Resources
- Khronos's OpenGL and GLSL wiki
- docs.gl: official OpenGL API documentation with added features
- MDN's list of best practices for WebGL
- Emscripten documentation's chapter on optimizing for WebGL
- SDL wiki
- Webassembly memory debugging article
Font
When initializing a Game object, the framework will attempt to load the font file BPmono.ttf
from the project root (where the compiled executable is located). If this file isn't found, the program can still run successfully, but the repository contains BPmono.ttf
if you want to create a symlink to the file in the project root.
History
These versions are available to checkout using tags.
- Disable logging by default
- Configure and enable/disable stdout and file logs separately
- Prevent GL error checking by default and add functions for allowing/disallowing
- Started tracking versioning using Git tags and a version string generated by Git
CI
SPACE🪐BOX doesn't have any CI features other than the tests, which are not automated. In the future, Gitea runners and/or git hooks may be used to implement merge protection.
License
SPACE🪐BOX is released under the zlib license. It is free to use, copy, and modify. Commercial use is permitted. See LICENSE.txt for details.
Included libraries are included under various permissive licenses compatible with the zlib license:
Library | License |
---|---|
BPmono.ttf | LICENSE_BPmono.txt |
gif-h | lib/gif-h/LICENSE |
GLEW | lib/glew/LICENSE.txt |
GLM | lib/glm/LICENSE |
nlohmann::json | lib/json/LICENSE.MIT |
SDL2-gfx | lib/sdl2-gfx/LICENSE |
superxbr.cpp | lib/superxbr.cpp |
CLI11 | lib/cli11/LICENSE |
Catch2 | [lib/catch2/LICENSE.txt](lib/catch2/LICENSE.txt |
Contact
Method | Contact information |
---|---|
cocktail.frank@dank.game | |
Web | https://dank.game |
X | https://x.com/diskmem |
PayPal | https://paypal.me/ohsqueezy |