Merged branch 'dev_native' into lm_sla_supports_auto

Added igl library files

src/igl/two_axis_valuator_fixed_up.h

@@ -0,0 +1,51 @@
+// This file is part of libigl, a simple c++ geometry processing library.
+// 
+// Copyright (C) 2013 Alec Jacobson <alecjacobson@gmail.com>
+// 
+// This Source Code Form is subject to the terms of the Mozilla Public License 
+// v. 2.0. If a copy of the MPL was not distributed with this file, You can 
+// obtain one at http://mozilla.org/MPL/2.0/.
+#ifndef IGL_TWO_AXIS_VALUATOR_FIXED_AXIS_UP_H
+#define IGL_TWO_AXIS_VALUATOR_FIXED_AXIS_UP_H
+
+#include "igl_inline.h"
+#include <Eigen/Core>
+#include <Eigen/Geometry>
+
+namespace igl
+{
+  // Applies a two-axis valuator drag rotation (as seen in Maya/Studio max) to a given rotation.
+  // Inputs:
+  //   w  width of the trackball context
+  //   h  height of the trackball context
+  //   speed  controls how fast the trackball feels, 1 is normal
+  //   down_quat  rotation at mouse down, i.e. the rotation we're applying the
+  //     trackball motion to (as quaternion). **Note:** Up-vector that is fixed
+  //     is with respect to this rotation.
+  //   down_x position of mouse down
+  //   down_y position of mouse down
+  //   mouse_x  current x position of mouse
+  //   mouse_y  current y position of mouse
+  // Outputs:
+  //   quat  the resulting rotation (as quaternion)
+  //
+  // See also: snap_to_fixed_up
+  template <typename Scalardown_quat, typename Scalarquat>
+  IGL_INLINE void two_axis_valuator_fixed_up(
+    const int w,
+    const int h,
+    const double speed,
+    const Eigen::Quaternion<Scalardown_quat> & down_quat,
+    const int down_x,
+    const int down_y,
+    const int mouse_x,
+    const int mouse_y,
+    Eigen::Quaternion<Scalarquat> & quat);
+}
+
+#ifndef IGL_STATIC_LIBRARY
+#  include "two_axis_valuator_fixed_up.cpp"
+#endif
+
+#endif
+