jolt-jni

JVM bindings for Jolt Physics

currently under construction

Jolt-jni provides a thin layer atop Jolt Physics, to facilitate physics simulation in JVM languages such as Java and Kotlin.

Translating JoltPhysics applications into Java

There’s close correspondence between the class/method names of JoltPhysics and jolt-jni. For example:

• The Body class in jolt-jni will eventually provide all the functionality of the Body class in Jolt Physics.
• The ConstBody interface will include all the const methods of the JoltPhysics Body class, such as its GetPosition() method, which in jolt-jni is called getPosition().

Things become slightly more interesting when C++ templates and public member data are involved:

• An array of body IDs is Array<BodyID> in JoltPhysics; in jolt-jni it’s called a BodyIdVector.
• The mConvexRadius member of the JoltPhysics BoxShapeSettings class is accessed using getConvexRadius() and setConvexRadius() in jolt-jni.

For a couple well-known JoltPhysics examples, direct translations into Java are provided.

How to add jolt-jni to an existing JVM project

Jolt-jni comes pre-built as a platform-independent JVM library plus a set of native libraries, all downloadable from Maven Central.

Current jolt-jni releases provide the JVM library under 6 distinct names (artifact IDs). They also provide 24 native libraries, each specific to a particular platform, build type, and build flavor.

Your runtime classpath should include a JVM library plus 1-to-6 native libraries: a native library for each platform on which the code will run.

Gradle-built projects

Add to the project’s "build.gradle" or "build.gradle.kts" file:

repositories {
    mavenCentral()
}
dependencies {
    implementation("com.github.stephengold:jolt-jni-Linux64:0.5.0") // JVM library
    runtimeOnly("com.github.stephengold:jolt-jni-Linux64:0.5.0:DebugSp") // native library for Linux
    // (Native libraries for other platforms could go here.)
}

• The "Linux64" platform name may be replaced by "Linux_ARM32hf", "Linux_ARM64", "MacOSX64", "MacOSX_ARM64", or "Windows64".
• The "DebugSp" classifier may be replaced by "DebugDp", "ReleaseSp", or "ReleaseDp".

External links

• The JoltPhysics repo at GitHub