From 965fa60bff8e8354bd01aadeaf721d1f03d4bc2a Mon Sep 17 00:00:00 2001
From: Christoph Haag <christoph.haag@collabora.com>
Date: Tue, 3 Nov 2020 23:11:09 +0100
Subject: [PATCH] xrt: Move synchronized state test into oxr session

The compositor now moves immediately to visible/focused when polling.
The state tracker will generate relevant openxr state changes once the session is synchronized.

Properly working alternative to e03ee48dcea88427ac3272ccab70bb665b1618a4 (reverted in e7643de8dbb10884736107284c2fdad56c7a6c83)
---
 src/xrt/compositor/main/comp_compositor.c | 17 ++++------
 src/xrt/compositor/main/comp_compositor.h |  6 ++--
 src/xrt/state_trackers/oxr/oxr_objects.h  |  3 ++
 src/xrt/state_trackers/oxr/oxr_session.c  | 39 ++++++++++-------------
 4 files changed, 29 insertions(+), 36 deletions(-)

diff --git a/src/xrt/compositor/main/comp_compositor.c b/src/xrt/compositor/main/comp_compositor.c
index afd58c7b1..c8005771d 100644
--- a/src/xrt/compositor/main/comp_compositor.c
+++ b/src/xrt/compositor/main/comp_compositor.c
@@ -210,9 +210,6 @@ compositor_wait_frame(struct xrt_compositor *xc,
 		*predicted_display_time = c->last_next_display_time;
 		*out_frame_id = c->last_next_display_time;
 
-		if (c->state == COMP_STATE_PREPARED) {
-			c->state = COMP_STATE_WAITED;
-		}
 		return XRT_SUCCESS;
 	}
 
@@ -246,9 +243,6 @@ compositor_wait_frame(struct xrt_compositor *xc,
 
 			c->last_next_display_time = next_display_time;
 
-			if (c->state == COMP_STATE_PREPARED) {
-				c->state = COMP_STATE_WAITED;
-			}
 			return XRT_SUCCESS;
 		}
 	}
@@ -529,14 +523,15 @@ compositor_poll_events(struct xrt_compositor *xc,
 	U_ZERO(out_xce);
 
 	switch (c->state) {
+	case COMP_STATE_UNINITIALIZED:
+		COMP_ERROR(c, "Polled uninitialized compositor");
+		out_xce->state.type = XRT_COMPOSITOR_EVENT_NONE;
+		break;
 	case COMP_STATE_READY:
 		out_xce->state.type = XRT_COMPOSITOR_EVENT_NONE;
 		break;
 	case COMP_STATE_PREPARED:
-		out_xce->state.type = XRT_COMPOSITOR_EVENT_NONE;
-		break;
-	case COMP_STATE_WAITED:
-		COMP_DEBUG(c, "WAITED -> VISIBLE");
+		COMP_DEBUG(c, "PREPARED -> VISIBLE");
 		out_xce->state.type = XRT_COMPOSITOR_EVENT_STATE_CHANGE;
 		out_xce->state.visible = true;
 		c->state = COMP_STATE_VISIBLE;
@@ -1373,6 +1368,8 @@ xrt_gfx_provider_create_native(struct xrt_device *xdev)
 
 	c->compositor_frame_times.debug_var = ft;
 
+	c->state = COMP_STATE_READY;
+
 	return &c->base;
 }
 
diff --git a/src/xrt/compositor/main/comp_compositor.h b/src/xrt/compositor/main/comp_compositor.h
index 9448704be..94cf7dbcf 100644
--- a/src/xrt/compositor/main/comp_compositor.h
+++ b/src/xrt/compositor/main/comp_compositor.h
@@ -127,9 +127,9 @@ struct comp_layer_slot
  */
 enum comp_state
 {
-	COMP_STATE_READY = 0,
-	COMP_STATE_PREPARED = 1,
-	COMP_STATE_WAITED = 2,
+	COMP_STATE_UNINITIALIZED = 0,
+	COMP_STATE_READY = 1,
+	COMP_STATE_PREPARED = 2,
 	COMP_STATE_VISIBLE = 3,
 	COMP_STATE_FOCUSED = 4,
 };
diff --git a/src/xrt/state_trackers/oxr/oxr_objects.h b/src/xrt/state_trackers/oxr/oxr_objects.h
index 0478c176e..63e8bc722 100644
--- a/src/xrt/state_trackers/oxr/oxr_objects.h
+++ b/src/xrt/state_trackers/oxr/oxr_objects.h
@@ -1258,6 +1258,9 @@ struct oxr_session
 	 */
 	bool has_ended_once;
 
+	bool compositor_visible;
+	bool compositor_focused;
+
 	bool frame_started;
 	bool exiting;
 
diff --git a/src/xrt/state_trackers/oxr/oxr_session.c b/src/xrt/state_trackers/oxr/oxr_session.c
index f9c872e2a..cdb5f5337 100644
--- a/src/xrt/state_trackers/oxr/oxr_session.c
+++ b/src/xrt/state_trackers/oxr/oxr_session.c
@@ -232,7 +232,8 @@ oxr_session_poll(struct oxr_logger *log, struct oxr_session *sess)
 		return;
 	}
 
-	while (true) {
+	bool read_more_events = true;
+	while (read_more_events) {
 		union xrt_compositor_event xce = {0};
 		xc->poll_events(xc, &xce);
 
@@ -240,29 +241,11 @@ oxr_session_poll(struct oxr_logger *log, struct oxr_session *sess)
 		switch (xce.type) {
 		case XRT_COMPOSITOR_EVENT_NONE:
 			// No more events.
-			return;
+			read_more_events = false;
+			break;
 		case XRT_COMPOSITOR_EVENT_STATE_CHANGE:
-			if (xce.state.visible &&
-			    sess->state == XR_SESSION_STATE_SYNCHRONIZED) {
-				oxr_session_change_state(
-				    log, sess, XR_SESSION_STATE_VISIBLE);
-			}
-			if (xce.state.focused &&
-			    sess->state == XR_SESSION_STATE_VISIBLE) {
-				oxr_session_change_state(
-				    log, sess, XR_SESSION_STATE_FOCUSED);
-			}
-
-			if (!xce.state.focused &&
-			    sess->state == XR_SESSION_STATE_FOCUSED) {
-				oxr_session_change_state(
-				    log, sess, XR_SESSION_STATE_VISIBLE);
-			}
-			if (!xce.state.visible &&
-			    sess->state == XR_SESSION_STATE_VISIBLE) {
-				oxr_session_change_state(
-				    log, sess, XR_SESSION_STATE_SYNCHRONIZED);
-			}
+			sess->compositor_visible = xce.state.visible;
+			sess->compositor_focused = xce.state.focused;
 			break;
 		case XRT_COMPOSITOR_EVENT_OVERLAY_CHANGE:
 			oxr_event_push_XrEventDataMainSessionVisibilityChangedEXTX(
@@ -273,6 +256,16 @@ oxr_session_poll(struct oxr_logger *log, struct oxr_session *sess)
 			break;
 		}
 	}
+
+	if (sess->state == XR_SESSION_STATE_SYNCHRONIZED &&
+	    sess->compositor_visible) {
+		oxr_session_change_state(log, sess, XR_SESSION_STATE_VISIBLE);
+	}
+
+	if (sess->state == XR_SESSION_STATE_VISIBLE &&
+	    sess->compositor_focused) {
+		oxr_session_change_state(log, sess, XR_SESSION_STATE_FOCUSED);
+	}
 }
 
 XrResult