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ArAugmentedImage

An image being detected and tracked by ARCore.

Summary

Enumerations
`ArAugmentedImageTrackingMethod{ AR_AUGMENTED_IMAGE_TRACKING_METHOD_NOT_TRACKING = 0, AR_AUGMENTED_IMAGE_TRACKING_METHOD_FULL_TRACKING = 1, AR_AUGMENTED_IMAGE_TRACKING_METHOD_LAST_KNOWN_POSE = 2 }`	enum Defines the current tracking mode for an Augmented Image.

Typedefs
`ArAugmentedImage`	typedef `struct ArAugmentedImage_` An image that has been detected and tracked (reference type, long-lived).

Functions
`ArAugmentedImage_acquireName(const ArSession session, const ArAugmentedImage augmented_image, char **out_augmented_image_name)`	`void` Returns the name of this image.
`ArAugmentedImage_getCenterPose(const ArSession session, const ArAugmentedImage augmented_image, ArPose *out_pose)`	`void` Returns the pose of the center of the Augmented Image, in world coordinates.
`ArAugmentedImage_getExtentX(const ArSession session, const ArAugmentedImage augmented_image, float *out_extent_x)`	`void` Retrieves the estimated width, in metres, of the corresponding physical image, as measured along the local X-axis of the coordinate space with origin and axes as defined by `ArAugmentedImage_getCenterPose`.
`ArAugmentedImage_getExtentZ(const ArSession session, const ArAugmentedImage augmented_image, float *out_extent_z)`	`void` Retrieves the estimated height, in metres, of the corresponding physical image, as measured along the local Z-axis of the coordinate space with origin and axes as defined by `ArAugmentedImage_getCenterPose`.
`ArAugmentedImage_getIndex(const ArSession session, const ArAugmentedImage augmented_image, int32_t *out_index)`	`void` Returns the zero-based positional index of this image from its originating image database.
`ArAugmentedImage_getTrackingMethod(const ArSession session, const ArAugmentedImage image, ArAugmentedImageTrackingMethod *out_tracking_method)`	`void` Returns the current method being used to track this Augmented Image.

Enumerations

ArAugmentedImageTrackingMethod

 ArAugmentedImageTrackingMethod

Defines the current tracking mode for an Augmented Image.

To retrieve the tracking mode for an image use ArAugmentedImage_getTrackingMethod.

Properties
`AR_AUGMENTED_IMAGE_TRACKING_METHOD_FULL_TRACKING`	The Augmented Image is currently being tracked using the camera image.
`AR_AUGMENTED_IMAGE_TRACKING_METHOD_LAST_KNOWN_POSE`	The Augmented Image is currently being tracked based on its last known pose, because it can no longer be tracked using the camera image.
`AR_AUGMENTED_IMAGE_TRACKING_METHOD_NOT_TRACKING`	The Augmented Image is not currently being tracked.

Typedefs

ArAugmentedImage

struct ArAugmentedImage_ ArAugmentedImage

An image that has been detected and tracked (reference type, long-lived).

Trackable type: AR_TRACKABLE_AUGMENTED_IMAGE
Release with: ArTrackable_release

Functions

ArAugmentedImage_acquireName

void ArAugmentedImage_acquireName(
  const ArSession *session,
  const ArAugmentedImage *augmented_image,
  char **out_augmented_image_name
)

Returns the name of this image.

The image name is not guaranteed to be unique.

This function will allocate memory for the name string, and set *out_augmented_image_name to point to that string. The caller must release the string using ArString_release when the string is no longer needed.

ArAugmentedImage_getCenterPose

void ArAugmentedImage_getCenterPose(
  const ArSession *session,
  const ArAugmentedImage *augmented_image,
  ArPose *out_pose
)

Returns the pose of the center of the Augmented Image, in world coordinates.

The pose's transformed +Y axis will be the normal out of the plane. The pose's transformed +X axis points from left to right on the image, and the transformed +Z axis points from top to bottom on the image.

If the tracking state is AR_TRACKING_STATE_PAUSED or AR_TRACKING_STATE_STOPPED, this returns the pose when the image state was last AR_TRACKING_STATE_TRACKING, or the identity pose if the image state has never been AR_TRACKING_STATE_TRACKING.

ArAugmentedImage_getExtentX

void ArAugmentedImage_getExtentX(
  const ArSession *session,
  const ArAugmentedImage *augmented_image,
  float *out_extent_x
)

Retrieves the estimated width, in metres, of the corresponding physical image, as measured along the local X-axis of the coordinate space with origin and axes as defined by ArAugmentedImage_getCenterPose.

ARCore will attempt to estimate the physical image's width and continuously update this estimate based on its understanding of the world. If the optional physical size is specified in the image database, this estimation process will happen more quickly. However, the estimated size may be different from the originally specified size.

If the tracking state is AR_TRACKING_STATE_PAUSED or AR_TRACKING_STATE_STOPPED, this returns the estimated width when the image state was last AR_TRACKING_STATE_TRACKING. If the image state has never been AR_TRACKING_STATE_TRACKING, this returns 0, even the image has a specified physical size in the image database.

ArAugmentedImage_getExtentZ

void ArAugmentedImage_getExtentZ(
  const ArSession *session,
  const ArAugmentedImage *augmented_image,
  float *out_extent_z
)

Retrieves the estimated height, in metres, of the corresponding physical image, as measured along the local Z-axis of the coordinate space with origin and axes as defined by ArAugmentedImage_getCenterPose.

ARCore will attempt to estimate the physical image's height and continuously update this estimate based on its understanding of the world. If an optional physical size is specified in the image database, this estimation process will happen more quickly. However, the estimated size may be different from the originally specified size.

If the tracking state is AR_TRACKING_STATE_PAUSED or AR_TRACKING_STATE_STOPPED, this returns the estimated height when the image state was last AR_TRACKING_STATE_TRACKING. If the image state has never been AR_TRACKING_STATE_TRACKING, this returns 0, even the image has a specified physical size in the image database.

ArAugmentedImage_getIndex

void ArAugmentedImage_getIndex(
  const ArSession *session,
  const ArAugmentedImage *augmented_image,
  int32_t *out_index
)

Returns the zero-based positional index of this image from its originating image database.

This index serves as the unique identifier for the image in the database.

ArAugmentedImage_getTrackingMethod

void ArAugmentedImage_getTrackingMethod(
  const ArSession *session,
  const ArAugmentedImage *image,
  ArAugmentedImageTrackingMethod *out_tracking_method
)

Returns the current method being used to track this Augmented Image.