Skip to content

Tracing Downcalls

squid233 edited this page Aug 9, 2025 · 1 revision

You may trace downcall invocation by specifying a system property overrungl.trace.downcalls. To enable it, add -Doverrungl.trace.downcalls=true to JVM arguments.

The downcall invocation are logged to the API logger (default to System.err). To specify the API logger, use OverrunGL::setApiLogger.

OverrunGL.setApiLogger(msg -> log.debug("{}", msg));

When downcall tracing is enabled, you should see messages where your specified API logger logs.

glfwInit()
glfwCreateWindow(640, 480, MemorySegment{ address: 0x1e3e16f5760, byteSize: 6 }, MemorySegment{ address: 0x0, byteSize: 0 }, MemorySegment{ address: 0x0, byteSize: 0 })
glfwDestroyWindow(MemorySegment{ address: 0x1e39baf9150, byteSize: 0 })
glfwTerminate()

Note that downcall tracing can largely decrease the performance of your application.

Clone this wiki locally