source: framspy/recording-body-coords.sim @ 1288

# The recording of the "center of gravity" (or mass) of all Parts of a creature during its lifespan, and
# the recording of coordinates of all Parts are stored as data->bodyrecording.
# Use STORE_ALL_PART_COORDS below to decide how much data you need recorded - maybe only COG and no Parts.
#
# If STORE_ALL_PART_COORDS=0 below, only COG is stored and the format is
# [ [cog1x,cog1y,cog1z], [cog2x,cog2y,cog2z], [cog3x,cog3y,cog3z], ...]
# where numbers are simulation steps.
# So you get a vector of COG x,y,z coordinates repeated for every simulation step.
#
# If STORE_ALL_PART_COORDS=1 below, the format is more verbose with one more level of nesting, because after the COG,
# the list of coordinates of all Parts follows (the first number below is the simulation step, the second is Part number)
# [ [[cog1x,cog1y,cog1z], [p1_1x,p1_1y,p1_1z], [p1_2x,p1_2y,p1_2z], ...], ...]
#
# You can further limit the amount of stored data by recording coordinates less frequently - see onCreaturesStep() comment below.
# Adjust 'Energy0' to achieve the lifespan you need.
# 'evalcount' should likely be 1 unless you need other performance criteria (like vertpos or distance) averaged from multiple evaluations.
# Put this file in the "data" subdirectory within the Framsticks distribution unless you prefer to provide its path when loading.

sim_params:
expdef:standard-eval
evalplan:~
:numparts,numjoints,numneurons,numconnections,instances,lifespan,velocity,distance,vertvel,vertpos,fit,fit_stdev,time,data->bodyrecording~
usercode:~
function onBorn(cr)
{
        super_onBorn(cr);
        cr.data->bodyrecording=[]; //create key and initialize its value in the "data" dictionary
}

function onCreaturesStep(cr) //change to onCreaturesUpdate(cr) if you want to record every "perfperiod" steps instead of every single step
{
        //super_onCreaturesStep(cr); //there is no onCreaturesStep() defined in parent expdef
        record(cr);
}

function addGenotypePerformanceFromCreature(g, cr) //this function is called twice per one evaluation, see comments in super_addGenotypePerformanceFromCreature(). For each evaluation, it is called once with g.instances=0 and empty g.data (to collect a single copy of cr.data) and then once again for instances>=0 (to aggregate cr.data into g.data according to a custom logic implemented in this function).
/*
For example for evalcount=3, if we wanted to aggregate vectors by appending them:
evaluation #1, instances=0: we append [1,2,3] to empty
evaluation #1, instances=0: we append [1,2,3] to empty
evaluation #2, instances=0: we append [4,5,6] to empty
evaluation #2, instances=1: we append [4,5,6] to [1,2,3]
evaluation #3, instances=0: we append [7,8,9] to empty
evaluation #3, instances=2: we append [7,8,9] to [1,2,3],[4,5,6]
*/
{
        //In the code below, we do not support evalcount>1, i.e. we do not collect more information from more evaluations. The last evaluation wins, so we do not have any "aggregation logic" here.
        //Simulator.print(g.instances); //for debugging double-calls if we ever wanted to have some aggregation logic (then also display g.data)
        super_addGenotypePerformanceFromCreature(g, cr);

        g.data->bodyrecording = cr.data->bodyrecording; //no averaging or any other form of aggregation - here assuming we only evaluate a genotype once; if not, then we ignore (overwrite) recordings from previous evaluations
        
        //Simulator.print("Recorded time steps: %d" % g.data->bodyrecording.size); //just for debugging
        return g;
}


// If needed, you can modify the function below to record the bounding box of the agent (to know the extreme values of Part coordinates
// without recording the coordinates of all Parts), to record MechJoint propertes, Neuro signals etc. See available fields in
// http://www.framsticks.com/files/classdoc/c_creature.html
function record(cr)
{
        const STORE_ALL_PART_COORDS = 1; //set to 0 to significantly reduce the amount of data recorded (will only record COG, not all Parts)
        if (cr.perf_measuring == 1) //record body position only when the creature is in the "performance measuring" period
        {
                var cog = cr.centerOfGravity;
                cog = [cog.x, cog.y, cog.z];
                if (STORE_ALL_PART_COORDS)
                {
                        var now = [cog];
                        for (var j=0; j<cr.numparts; j++)
                        {
                                var part = cr.getMechPart(j);
                                now.add([part.x, part.y, part.z]);
                        }
                        cr.data->bodyrecording.add(now);
                } else
                        cr.data->bodyrecording.add(cog);
        }
}

~