xrt: add hand_tracking_image_boundary_info

src/xrt/drivers/ht/ht_driver.c

@@ -286,7 +286,26 @@ ht_device_create_index(struct xrt_prober *xp, struct t_stereo_camera_calibration
 	if (use_old_rgb) {
 		sync = t_hand_tracking_sync_old_rgb_create(calib);
 	} else {
-		sync = t_hand_tracking_sync_mercury_create(calib, HT_OUTPUT_SPACE_LEFT_CAMERA);
+
+		struct hand_tracking_image_boundary_info info;
+		info.views[0].type = HT_IMAGE_BOUNDARY_CIRCLE;
+		info.views[1].type = HT_IMAGE_BOUNDARY_CIRCLE;
+
+
+		//!@todo This changes by like 50ish pixels from device to device. For now, the solution is simple: just
+		//! make the circle a bit bigger than we'd like.
+		// Maybe later we can do vignette calibration? Write a tiny optimizer that tries to fit Index's
+		// gradient? Unsure.
+		info.views[0].boundary.circle.normalized_center.x = 0.5f;
+		info.views[0].boundary.circle.normalized_center.y = 0.5f;
+
+		info.views[1].boundary.circle.normalized_center.x = 0.5f;
+		info.views[1].boundary.circle.normalized_center.y = 0.5f;
+
+		info.views[0].boundary.circle.normalized_radius = 0.55;
+		info.views[1].boundary.circle.normalized_radius = 0.55;
+
+		sync = t_hand_tracking_sync_mercury_create(calib, HT_OUTPUT_SPACE_LEFT_CAMERA, info);
 	}
 
 	struct ht_device *htd = ht_device_create_common(calib, true, &finder.xfctx, sync);
@@ -340,6 +359,7 @@ ht_device_create(struct xrt_frame_context *xfctx,
                  struct t_stereo_camera_calibration *calib,
                  enum hand_tracking_output_space output_space,
                  enum hand_tracking_algorithm algorithm_choice,
+                 struct hand_tracking_image_boundary_info boundary_info,
                  struct xrt_slam_sinks **out_sinks,
                  struct xrt_device **out_device)
 {
@@ -347,7 +367,7 @@ ht_device_create(struct xrt_frame_context *xfctx,
 	XRT_TRACE_MARKER();
 	assert(calib != NULL);
 
-	struct t_hand_tracking_sync *sync = t_hand_tracking_sync_mercury_create(calib, output_space);
+	struct t_hand_tracking_sync *sync = t_hand_tracking_sync_mercury_create(calib, output_space, boundary_info);
 
 	struct ht_device *htd = ht_device_create_common(calib, false, xfctx, sync);
 
@@ -380,7 +400,11 @@ ht_device_create_depthai_ov9282()
 
 	struct t_hand_tracking_sync *sync;
 
-	sync = t_hand_tracking_sync_mercury_create(calib, HT_OUTPUT_SPACE_LEFT_CAMERA);
+	struct hand_tracking_image_boundary_info info;
+	info.views[0].type = HT_IMAGE_BOUNDARY_NONE;
+	info.views[1].type = HT_IMAGE_BOUNDARY_NONE;
+
+	sync = t_hand_tracking_sync_mercury_create(calib, HT_OUTPUT_SPACE_LEFT_CAMERA, info);
 
 	struct ht_device *htd = ht_device_create_common(calib, true, &xfctx, sync);
 

src/xrt/drivers/ht/ht_interface.h

@@ -57,6 +57,7 @@ ht_device_create(struct xrt_frame_context *xfctx,
                  struct t_stereo_camera_calibration *calib,
                  enum hand_tracking_output_space output_space,
                  enum hand_tracking_algorithm algorithm_choice,
+                 struct hand_tracking_image_boundary_info boundary_info,
                  struct xrt_slam_sinks **out_sinks,
                  struct xrt_device **out_device);
 

src/xrt/drivers/wmr/wmr_hmd.c

@@ -1486,11 +1486,17 @@ wmr_hmd_hand_track(struct wmr_hmd *wh,
 	struct xrt_device *device = NULL;
 
 #ifdef XRT_BUILD_DRIVER_HANDTRACKING
+	//!@todo Turning it off is okay for now, but we should plug metric_radius (or whatever it's called) in, at some
+	//! point.
+	struct hand_tracking_image_boundary_info boundary_info;
+	boundary_info.views[0].type = HT_IMAGE_BOUNDARY_NONE;
+	boundary_info.views[1].type = HT_IMAGE_BOUNDARY_NONE;
 
 	int create_status = ht_device_create(&wh->tracking.xfctx,         //
 	                                     stereo_calib,                //
 	                                     HT_OUTPUT_SPACE_LEFT_CAMERA, //
 	                                     HT_ALGORITHM_MERCURY,        //
+	                                     boundary_info,               //
 	                                     &sinks,                      //
 	                                     &device);
 	if (create_status != 0) {

src/xrt/include/tracking/t_hand_tracking.h

@@ -30,6 +30,37 @@ enum hand_tracking_algorithm
 	HT_ALGORITHM_OLD_RGB
 };
 
+enum hand_tracking_image_boundary_type
+{
+	HT_IMAGE_BOUNDARY_NONE,
+	HT_IMAGE_BOUNDARY_CIRCLE,
+};
+
+struct hand_tracking_image_boundary_circle
+{
+	// The center, in normalized 0-1 UV coordinates.
+	// Should probably be between 0 and 1 in pixel coordinates.
+	struct xrt_vec2 normalized_center;
+	// The radius, divided by the image width.
+	// For Index, should be around 0.5.
+	float normalized_radius;
+};
+
+struct hand_tracking_image_boundary_info_one_view
+{
+	enum hand_tracking_image_boundary_type type;
+	union {
+		struct hand_tracking_image_boundary_circle circle;
+	} boundary;
+};
+
+
+struct hand_tracking_image_boundary_info
+{
+	//!@todo Hardcoded to 2 - needs to increase as we support headsets with more cameras.
+	struct hand_tracking_image_boundary_info_one_view views[2];
+};
+
 /*!
  * Synchronously processes frames and returns two hands.
  */

src/xrt/tracking/hand/mercury/hg_interface.h

@@ -8,6 +8,7 @@
  * @ingroup aux_tracking
  */
 #pragma once
+#include "xrt/xrt_defines.h"
 #include "tracking/t_tracking.h"
 #include "tracking/t_hand_tracking.h"
 
@@ -22,7 +23,8 @@ extern "C" {
  */
 struct t_hand_tracking_sync *
 t_hand_tracking_sync_mercury_create(struct t_stereo_camera_calibration *calib,
-                                    enum hand_tracking_output_space output_space);
+                                    enum hand_tracking_output_space output_space,
+                                    struct hand_tracking_image_boundary_info boundary_info);
 
 #ifdef __cplusplus
 } // extern "C"

src/xrt/tracking/hand/mercury/hg_sync.cpp

@@ -491,7 +491,9 @@ HandTracking::cCallbackDestroy(t_hand_tracking_sync *ht_sync)
  */
 
 extern "C" t_hand_tracking_sync *
-t_hand_tracking_sync_mercury_create(struct t_stereo_camera_calibration *calib, hand_tracking_output_space output_space)
+t_hand_tracking_sync_mercury_create(struct t_stereo_camera_calibration *calib,
+                                    enum hand_tracking_output_space output_space,
+                                    struct hand_tracking_image_boundary_info boundary_info)
 {
 	XRT_TRACE_MARKER();