docs/cache.md

Understanding the data format and classes

OpenScene is a compact redistribution of the large-scale nuPlan dataset, retaining only relevant annotations and sensor data at 2Hz. This reduces the dataset size by a factor of >10. The data used in NAVSIM is structured into navsim.common.dataclasses.Scene objects. A Scene is a list of Frame objects, each containing the required inputs and annotations for training a planning Agent.

Caching. Evaluating planners involves significant preprocessing of the raw annotation data, including accessing the global map at each ´Frame´ and converting it into a local coordinate system. You can generate the cache with:

cd $NAVSIM_DEVKIT_ROOT/scripts/
./run_metric_caching.sh

This will create the metric cache under $NAVSIM_EXP_ROOT/metric_cache, where $NAVSIM_EXP_ROOT is defined by the environment variable set during installation.