From 60cd63027129383dc28ad9f1e37c5ed378a2d427 Mon Sep 17 00:00:00 2001
From: Jakob Bornecrantz <jakob@collabora.com>
Date: Sun, 6 Mar 2022 12:33:28 +0000
Subject: [PATCH] tracking: Add new hand tracking interface header

Co-authored-by: Moses Turner <moses@collabora.com>
---
 src/xrt/include/tracking/t_hand_tracking.h | 107 +++++++++++++++++++++
 1 file changed, 107 insertions(+)
 create mode 100644 src/xrt/include/tracking/t_hand_tracking.h

diff --git a/src/xrt/include/tracking/t_hand_tracking.h b/src/xrt/include/tracking/t_hand_tracking.h
new file mode 100644
index 000000000..cd0bb15fc
--- /dev/null
+++ b/src/xrt/include/tracking/t_hand_tracking.h
@@ -0,0 +1,107 @@
+// Copyright 2022, Collabora, Ltd.
+// SPDX-License-Identifier: BSL-1.0
+/*!
+ * @file
+ * @brief  Hand tracking interfaces.
+ * @author Jakob Bornecrantz <jakob@collabora.com>
+ * @ingroup xrt_iface
+ */
+
+#pragma once
+
+#include "xrt/xrt_defines.h"
+#include "xrt/xrt_frame.h"
+
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+
+// /*!
+//  * Result of a two hand tracking processing.
+//  */
+// struct t_hand_tracking_result_two
+// {
+// 	struct xrt_hand_joint_set hands[2]; // left, right
+// };
+
+/*!
+ * Synchronously processes frames and returns two hands.
+ */
+struct t_hand_tracking_sync
+{
+	/*!
+	 * Process left and right view and get back a result synchronously.
+	 */
+	void (*process)(struct t_hand_tracking_sync *ht_sync,
+	                struct xrt_frame *left_frame,
+	                struct xrt_frame *right_frame,
+	                struct xrt_hand_joint_set *out_left_hand,
+	                struct xrt_hand_joint_set *out_right_hand,
+	                uint64_t *out_timestamp_ns);
+
+	/*!
+	 * Destroy this hand tracker sync object.
+	 */
+	void (*destroy)(struct t_hand_tracking_sync *ht_sync);
+};
+
+/*!
+ * @copydoc t_hand_tracking_sync::process
+ *
+ * @public @memberof t_hand_tracking_sync
+ */
+static inline void
+t_ht_sync_process(struct t_hand_tracking_sync *ht_sync,
+                  struct xrt_frame *left_frame,
+                  struct xrt_frame *right_frame,
+                  struct xrt_hand_joint_set *out_left_hand,
+                  struct xrt_hand_joint_set *out_right_hand,
+                  uint64_t *out_timestamp_ns)
+{
+	ht_sync->process(ht_sync, left_frame, right_frame, out_left_hand, out_right_hand, out_timestamp_ns);
+}
+
+/*!
+ * @copydoc t_hand_tracking_sync::destroy
+ *
+ * Helper for calling through the function pointer: does a null check and sets
+ * ht_sync_ptr to null if freed.
+ *
+ * @public @memberof t_hand_tracking_sync
+ */
+static inline void
+t_ht_sync_destroy(struct t_hand_tracking_sync **ht_sync_ptr)
+{
+	struct t_hand_tracking_sync *ht_sync = *ht_sync_ptr;
+	if (ht_sync == NULL) {
+		return;
+	}
+
+	ht_sync->destroy(ht_sync);
+	*ht_sync_ptr = NULL;
+}
+
+struct t_hand_tracking_async
+{
+	struct xrt_frame_node node;
+	struct xrt_frame_sink left;
+	struct xrt_frame_sink right;
+
+	void (*get_hand)(struct t_hand_tracking_async *ht_async,
+	                 enum xrt_input_name name,
+	                 uint64_t desired_timestamp_ns,
+	                 struct xrt_hand_joint_set *out_value,
+	                 uint64_t *out_timestamp_ns);
+
+	void (*destroy)(struct t_hand_tracking_async *ht_async);
+};
+
+struct t_hand_tracking_async *
+t_hand_tracking_async_default_create(struct xrt_frame_context *xfctx, struct t_hand_tracking_sync *sync);
+
+
+#ifdef __cplusplus
+} // extern "C"
+#endif