From: Mikko Rasa <tdb@tdb.fi>
Date: Wed, 5 Oct 2016 23:32:53 +0000 (+0300)
Subject: Store the base matrix of HeadTrackingCamera and provice access to it
X-Git-Url: http://git.tdb.fi/?a=commitdiff_plain;h=c3de3d030e663319289ce39aef1e8b21c3b47084;p=libs%2Fvr.git

Store the base matrix of HeadTrackingCamera and provice access to it

It will be useful for positioning other tracked devices.
---

diff --git a/source/headtrackingcamera.cpp b/source/headtrackingcamera.cpp
index 86d6e24..9f4dd5c 100644
--- a/source/headtrackingcamera.cpp
+++ b/source/headtrackingcamera.cpp
@@ -21,10 +21,12 @@ void HeadTrackingCamera::update_from_matrix(const GL::Matrix &hmd_matrix)
 	columns[0] = compose(right, 0.0f);
 	columns[1] = compose(up, 0.0f);
 	columns[2] = compose(cross(right, up), 0.0f);
-	columns[3] = compose(base_camera.get_position(), 1.0f);
-	GL::Matrix matrix = GL::Matrix::from_columns(columns)*hmd_matrix;
+	columns[3] = compose(base_camera.get_position()+base_camera.get_up_direction()*elevation_offset, 1.0f);
+	base_matrix = GL::Matrix::from_columns(columns);
 
-	set_position(matrix*GL::Vector3()+base_camera.get_up_direction()*elevation_offset);
+	GL::Matrix matrix = base_matrix*hmd_matrix;
+
+	set_position(matrix*GL::Vector3());
 	set_look_direction((matrix*GL::Vector4(0, 0, -1, 0)).slice<3>(0));
 	set_up_direction((matrix*GL::Vector4(0, 1, 0, 0)).slice<3>(0));
 
diff --git a/source/headtrackingcamera.h b/source/headtrackingcamera.h
index c200136..a10c1e1 100644
--- a/source/headtrackingcamera.h
+++ b/source/headtrackingcamera.h
@@ -10,12 +10,15 @@ class HeadTrackingCamera: public Msp::GL::Camera
 {
 protected:
 	const GL::Camera &base_camera;
+	GL::Matrix base_matrix;
 	float elevation_offset;
 
 	HeadTrackingCamera(const GL::Camera &);
 public:
 	virtual ~HeadTrackingCamera() { }
 
+	const GL::Matrix &get_base_matrix() const { return base_matrix; }
+
 	void set_elevation_offset(float);
 	virtual void reset_tracking() { }
 	virtual void update() = 0;