[apriltag] AprilTagFieldLayout: Add accessors for origin and field dimensions (#5869)

apriltag/src/main/java/edu/wpi/first/apriltag/AprilTagFieldLayout.java

@@ -113,6 +113,26 @@ public class AprilTagFieldLayout {
     return new ArrayList<>(m_apriltags.values());
   }
 
+  /**
+   * Returns the length of the field the layout is representing in meters.
+   *
+   * @return length, in meters
+   */
+  @JsonIgnore
+  public double getFieldLength() {
+    return m_fieldDimensions.fieldLength;
+  }
+
+  /**
+   * Returns the length of the field the layout is representing in meters.
+   *
+   * @return width, in meters
+   */
+  @JsonIgnore
+  public double getFieldWidth() {
+    return m_fieldDimensions.fieldWidth;
+  }
+
   /**
    * Sets the origin based on a predefined enumeration of coordinate frame origins. The origins are
    * calculated from the field dimensions.
@@ -152,6 +172,16 @@ public class AprilTagFieldLayout {
     m_origin = origin;
   }
 
+  /**
+   * Returns the origin used for tag pose transformation.
+   *
+   * @return the origin
+   */
+  @JsonIgnore
+  public Pose3d getOrigin() {
+    return m_origin;
+  }
+
   /**
    * Gets an AprilTag pose by its ID.
    *

apriltag/src/main/native/cpp/AprilTagFieldLayout.cpp

@@ -41,6 +41,14 @@ AprilTagFieldLayout::AprilTagFieldLayout(std::vector<AprilTag> apriltags,
   }
 }
 
+units::meter_t AprilTagFieldLayout::GetFieldLength() const {
+  return m_fieldLength;
+}
+
+units::meter_t AprilTagFieldLayout::GetFieldWidth() const {
+  return m_fieldWidth;
+}
+
 void AprilTagFieldLayout::SetOrigin(OriginPosition origin) {
   switch (origin) {
     case OriginPosition::kBlueAllianceWallRightSide:
@@ -59,6 +67,10 @@ void AprilTagFieldLayout::SetOrigin(const Pose3d& origin) {
   m_origin = origin;
 }
 
+Pose3d AprilTagFieldLayout::GetOrigin() const {
+  return m_origin;
+}
+
 std::optional<frc::Pose3d> AprilTagFieldLayout::GetTagPose(int ID) const {
   const auto& it = m_apriltags.find(ID);
   if (it == m_apriltags.end()) {

apriltag/src/main/native/include/frc/apriltag/AprilTagFieldLayout.h

@@ -62,6 +62,18 @@ class WPILIB_DLLEXPORT AprilTagFieldLayout {
   AprilTagFieldLayout(std::vector<AprilTag> apriltags,
                       units::meter_t fieldLength, units::meter_t fieldWidth);
 
+  /**
+   * Returns the length of the field the layout is representing.
+   * @return length
+   */
+  units::meter_t GetFieldLength() const;
+
+  /**
+   * Returns the length of the field the layout is representing.
+   * @return width
+   */
+  units::meter_t GetFieldWidth() const;
+
   /**
    * Sets the origin based on a predefined enumeration of coordinate frame
    * origins. The origins are calculated from the field dimensions.
@@ -83,6 +95,12 @@ class WPILIB_DLLEXPORT AprilTagFieldLayout {
    */
   void SetOrigin(const Pose3d& origin);
 
+  /**
+   * Returns the origin used for tag pose transformation.
+   * @return the origin
+   */
+  Pose3d GetOrigin() const;
+
   /**
    * Gets an AprilTag pose by its ID.
    *