Eagle Robotics Path Visualizer

Based on github/RechargedGreen/RRPathVisualizer

Welcome! This repository contains a visualizer for FIRST Tech Challenge teams to plan and animate paths for the RoadRunner motion planning library. Originally developed by Recharged Green Robotics, this repository features additions from Eagle Robotics to improve path development and user experience.

Key features:

• Visualization of multiple RoadRunner trajectory groups to plan for many autonomous scenarios and starting positions
• Mouse tracking to aid in coordinate selection along with animation controls
• Easy mirroring of field positions to visualize either alliance color using infix functions
• Reflection-based configuration system that lets users change trajectory settings (e.g. alliance color, starting position) without recompiling or restarting the application
• Sharing of configuration variables across different trajectories using application-level "environment" config

How do I create a path?

The TrajectoryGen abstract class serves as the starting point for creating a custom trajectory. Create a new class extending TrajectoryGen within the root-level trajectories package to get started.
The createTrajectory() function must be implemented by each subclass and returns a list of trajectories. By default, the robot starting pose is set to (x=0, y=0, heading=0). To change this, set startPose to a new Pose2d instance as the first action within the method. It is better to set the starting pose within createTrajectory() rather than class initialization, as this allows for configuration updates, as will be discussed later. Additionally, instantiate a new ArrayList<Trajectory> variable.

To get a TrajectoryBuilder object, call the superclass builder() function. Pass a value to optional parameter tangent to set a custom starting tangent for the robot motion; otherwise, it will default to the current robot heading. To conform to functional programming style, do not use variables; instead, call a series of functions on the trajectory builder to add path elements.

When finished with a path, there are two options. Both of these options are custom for the path visualizer and will need to be replaced when copying to robot code in Android Studio.

• Call the saveAndBuild() method on the trajectory builder. This will return a Trajectory object but will also update the known start pose to be the end point of the build trajectory. This ensures that trajectories can be built in a series without having to manually update the starting pose. With this new object, manually add it to the list created earlier.
• Call the saveAndBuildTo(list: ArrayList<Trajectory>) method, which performs the same actions as saveAndBuild() but also adds the built trajectory to the list passed to the function.

Finally, return the list created earlier in the function.

Infix functions

The infix functions contained within classes extending TrajectoryGen classes provide easy capability for changing robot position based on the current alliance color or robot starting position. For example, the TrajectoryGenUltimateGoal class contains the following methods:

• Double.reverseIf(AllianceColor) flips the sign of a Double if the current alliance color matches the value passed to the function
• Double.reverseIf(StartingLine) flips the sign of a Double if the current starting line matches the value passed to the function

Ex. 6.0 reverseIf BLUE returns 6.0 if the set alliance color is RED or -6.0 if the set alliance color is BLUE. The infix functions contained within the TrajectoryGenUltimateGoal class provide easy capability for changing robot position based on the current alliance color or robot starting position.

Viewing trajectories

Any Kotlin class extending TrajectoryGen and stored in the trajectories package will automatically be loaded upon application start.

Extend the TrajectoryGenPowerPlay class to receive three built-in environment config variables that can be edited near the top of the application:

• Alliance color (red or blue)
• Starting row (row 2 or row 5 of field)
• Signal orientation (image 1, image 2, or image 3)

A drop-down menu at the top of the application can be used for swapping between the created trajectory generators.

Annotations

Config (for variables)

Add the @Config annotation to any Int, Double, Boolean, or enum class variable in the trajectory generator class to be able to edit this variable during runtime.

Parameters:

• Name (String): Designate an alternate name for the config item that will be shown instead during runtime. This will also replace the variable name for matching the variable to the environment config.
• Environment (Boolean): If true, the annotated variable will be considered an "environment" variable. The value of this will be shared (and automatically updated) with all other variables with the same name and type across different trajectory generators.

PrimaryTrajectory (for classes)

The first trajectory generator class found with the @PrimaryTrajectory annotation will be the first visualized upon application start.

Disabled (for classes)

Any trajectory generator class annotated with @Disabled will not be shown in the application.