Migrating from 0.5.x #

This document assesses the 1.0.0 API changes that will most affect teams using the library.

Packages #

Previously, classes were scattered across many subpackages of com.acmerobotics.roadrunner. Now everything can be found in the root package.

Trajectory Builder #

Most of the methods are the same and should feel familiar. The most notable change is splitting lineTo() into two methods, lineToX() and lineToY(). Line directions will now automatically match the path tangent for continuity unless setTangent() is called. Wherever possible, the trajectory builder encourages continuity.

Trajectory Sequences #

Trajectory sequences have been extended intoa a full actions system. Each action describes a task that executes in a bunch of small steps. For example, following a trajectory is an action made up of “read encoders, compute deviation from the trajectory, set motor powers, read encoders, compute deviation …”. The TrajectoryActionBuilder class takes the place of TrajectorySequenceBuilder in making it easy to combine following trajectories with moving servos, setting motor powers, and any other behaviors you might want.

Markers are included in the new system. Here’s an example:

builder
.lineToX(-12)
.afterDisp(5, dispMarker)
.splineTo(Vector2d(-24, -12), -Math.PI / 2)
.turn(Math.PI / 2)
.afterTime(0.5, tempMarker)
.turn(Math.PI / 2)
.setReversed(true)
.splineTo(Vector2d(-36, 0), Math.PI)

The action dispMarker triggers 5 units after the end of the first line and is similar to a displacement marker. The action tempMarker triggers half of a second after the first turn begins and is similar to a temporal marker.

PID Controller #

Some old classes didn’t make the cut for the new code. Among this group is PIDFController, which you can find here in Java. All of the other old files are still available on GitHub, and you can copy them into your codebase if you need to. Nothing is gone completely.