Configuration

JOML provides some configuration via JVM System Properties to change the behaviour of certain operations at runtime.

Properties

Property	Description	Values	Default	Since
joml.debug	Performs checks that impact performance but don't crash the JVM, such as checking whether only direct NIO Buffers are used when 'joml.nounsafe' is not set and sun.misc.Unsafe is available.	true (implicit), false	false
joml.nounsafe	Whether not to use sun.misc.Unsafe to accelerate memory copy operations, even if it is available. Please note that using joml.nounsafe will result in performance degradations of many operations, especially copying memory from/to arrays, NIO buffers and JOML objects	true (implicit), false	false
joml.fastmath	Whether fast approximations of some java.lang.Math operations should be used, most notably sin/cos. See the JavaDoc of the class org.joml.Math for more information.	true (implicit), false	false
joml.sinLookup	If joml.fastmath is used, then this controls whether to use a lookup table implementation of the sin/cos approximation. If false, then an arithmetic approximation is used. See the JavaDoc of the class org.joml.Math for more information.	true (implicit), false	false
joml.sinLookup.bits	If joml.sinLookup is used, then this controls the size of the lookup table. Lower values reduce the table size but lead to less accurate approximations.	integer	14
joml.format	If disabled, then a default NumberFormat instance with English locale is used to format all numbers in toString() instead of scientific notation.	true (implicit), false	true
joml.format.decimals	If joml.format is enabled, then this determines the number of decimal digits in the scientific notation used to format all numbers in toString().	integer	3
joml.useMathFma	If enabled, java.lang.Math.fma() is used in most matrix/vector/quaternion methods.	true (implicit), false	false	1.9.24
joml.forceUnsafe	If enabled, the use of sun.misc.Unsafe is forced. If it is not supported, then operations that would use it throw org.joml.ConfigurationException	true (implicit), false	false	1.9.25

Examples

To disable the use of sun.misc.Unsafe:

java -Djoml.nounsafe -jar yourapp.jar

To use fast lookup table approximations of sin/cos with 10 bits of table size:

java -Djoml.fastmath -Djoml.sinLookup -Djoml.sinLookup.bits=10 -jar yourapp.jar