Class SimVision

java.lang.Object

frc.robot.subsystems.vision.SimVision

public class SimVision
extends Object

Simulated cameras for every pose source, on PhotonLib's VisionSystemSim.

One PhotonLib vision system holds every AprilTag camera on the robot, the Limelights as well as the Orin's cameras, each with its own mount and camera properties. All of them look at the 2026 field from the simulated truth pose (see Swerve.SimErrors). The Orin cameras are read exactly as on the robot, by PhotonOrinIO over NetworkTables. The Limelights are read by SimVision.LimelightSimIO, which turns the same PhotonLib results into what a Limelight reports:

• MegaTag1 uses the multi-tag (or single-tag) solve, heading included.
• MegaTag2 solves translation from each tag with the heading the robot pushed, which is how MegaTag2 works and why it inherits gyro drift.
• Target size reports the largest target's area, as ta.

The QuestNav is SimVision.QuestSimIO: truth plus a slow random-walk drift, in a field frame that only lines up once the robot has sent a pose reset. Those are the two things a VIO source gets wrong.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static final class	SimVision.LimelightSimCamera	One simulated Limelight: PhotonLib results read once per loop, shared by MT1 and MT2.
static final class	SimVision.LimelightSimIO	A Limelight source backed by a PhotonLib sim camera.
static final class	SimVision.QuestSimIO	Simulated QuestNav: reports truth in its own frame, which lines up with the field only after SimVision.QuestSimIO.resetPose(Pose2d), plus a random-walk drift.

Constructor Summary

Constructors

Constructor	Description
SimVision(AprilTagFieldLayout layout, Supplier<Optional<Pose2d>> truth)

Method Summary

Modifier and Type	Method	Description
org.photonvision.PhotonCamera	addCamera(String name, org.photonvision.simulation.SimCameraProperties properties, Transform3d robotToCamera)	Adds a simulated camera that publishes as a PhotonVision camera named name.
Field2d	getDebugField()	Field2d showing what PhotonLib's sim sees (tags, cameras, robot).
static org.photonvision.simulation.SimCameraProperties	limelight4()	Properties of a Limelight 4 (1280x800, ~82 deg diagonal), per Limelight's spec sheet.
static Transform3d	robotToCamera(Limelight.LimelightConfig c)	A Limelight's mount in WPILib's robot frame (x forward, y left, z up).
static org.photonvision.simulation.SimCameraProperties	thriftiestCam()	Properties of a Thrifty Bot Thriftiest Cam (OV9281, 1280x800) as the Orin runs it.
void	update()	Moves every simulated camera to the current truth pose.

Methods inherited from class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

SimVision

public SimVision(AprilTagFieldLayout layout,
 Supplier<Optional<Pose2d>> truth)

Parameters:

layout - field tags

truth - simulated true robot pose

Method Details

update

public void update()

Moves every simulated camera to the current truth pose. Call once per loop, first.

getDebugField

public Field2d getDebugField()

Field2d showing what PhotonLib's sim sees (tags, cameras, robot).

limelight4

public static org.photonvision.simulation.SimCameraProperties limelight4()

Properties of a Limelight 4 (1280x800, ~82 deg diagonal), per Limelight's spec sheet.

thriftiestCam

public static org.photonvision.simulation.SimCameraProperties thriftiestCam()

Properties of a Thrifty Bot Thriftiest Cam (OV9281, 1280x800) as the Orin runs it.

addCamera

public org.photonvision.PhotonCamera addCamera(String name,
 org.photonvision.simulation.SimCameraProperties properties,
 Transform3d robotToCamera)

Adds a simulated camera that publishes as a PhotonVision camera named name.

Parameters:

name - camera name on NetworkTables

properties - sensor model

robotToCamera - mount

Returns:

the PhotonLib camera handle, to read results from

robotToCamera

public static Transform3d robotToCamera(Limelight.LimelightConfig c)

A Limelight's mount in WPILib's robot frame (x forward, y left, z up). Limelight's own convention is forward, right, up and pitch positive up; WPILib's pitch is positive down.