Logging
OPENRNDR uses kotlin-logging, which is a Kotlin flavoured wrapper around slf4j, to log its internal workings. Log messages are displayed in the IDE’s console and saved to the application.log file.
Configure logging
In build.gradle.kts we can modify the applicationLogging variable.
Logging.NONEto disable logging.Logging.SIMPLEto display monochrome log messages in the console.Logging.FULLto display coloured log messages in the console to distinguish their types.
In src/main/resources/log4j2.yaml we can change the logging level. To make it verbose we can replace level: info with level: all.
Exception handling
It is possible to change how exception errors are presented by IntelliJ Idea: Open the Run > Edit Configurations menu and make sure the VM Options text field contains -Dorg.openrndr.exceptions=JVM. This can sometimes help figure out why a program is crashing.
Crashing shaders
If a ShadeStyle crashes, a ShaderError.glsl file is created at the root of the project. The content of the file is the actual shader program OPENRNDR tried to use. Studying this program can help figure out why shaders fail. A common reason is using incorrect names for methods, uniforms or variables.
Debugging video exporting
When a video file is produced, a ffmpegOutput.txt is created at the root of the project. Studying this file can help diagnose problems with video exporting.
Enabling OpenGL debug messages
If your graphics hardware and drivers support OpenGL debug contexts you can open the Run > Edit Configurations... menu in IntelliJ and make sure the VM Options text field contains -Dorg.openrndr.gl3.debug=true to enable the debug messages.
Using RenderDoc
RenderDoc is a graphics debugger currently available for Vulkan, D3D11, D3D12, OpenGL, and OpenGL ES development on Windows, Linux, Android, Stadia, and Nintendo Switch™.
This post explains how to use RenderDoc with OPENRNDR.