From 0f40a4be8f5c0cce76672ce38a99ddc775478285 Mon Sep 17 00:00:00 2001
From: Moses Turner <moses@collabora.com>
Date: Sun, 21 Aug 2022 23:54:12 +0100
Subject: [PATCH] t/c/builder_lighthouse: Fail more clearly when cameras aren't
 available

---
 src/xrt/targets/common/target_builder_lighthouse.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/src/xrt/targets/common/target_builder_lighthouse.c b/src/xrt/targets/common/target_builder_lighthouse.c
index 3e86e7d53..d1f713beb 100644
--- a/src/xrt/targets/common/target_builder_lighthouse.c
+++ b/src/xrt/targets/common/target_builder_lighthouse.c
@@ -638,8 +638,21 @@ lighthouse_open_system(struct xrt_builder *xb,
 		lhs.vive_tstatus.hand_enabled = false;
 	}
 
+
+
 	bool success = true;
 
+	if (hmd_config == NULL) {
+		// This should NEVER happen, but we're not writing Rust.
+		U_LOG_E("Didn't get a vive config? Not creating visual trackers.");
+		goto end;
+	}
+	if (!hmd_config->cameras.valid) {
+		U_LOG_I(
+		    "HMD didn't have cameras or didn't have a valid camera calibration. Not creating visual trackers.");
+		goto end;
+	}
+
 	struct xrt_slam_sinks sinks = {0};
 	struct xrt_device *hand_devices[2] = {NULL};
 	success = setup_visual_trackers(usysd, xp, hmd_config, &sinks, hand_devices);