mirror of
https://gitlab.com/libeigen/eigen.git
synced 2024-12-21 07:19:46 +08:00
5e9ee8863e
- quaternion vs euler angles interpolation (though the Euler angle version looks a bit too bad) - navigation using either a mapping from 2D screen coordinates to 3D points on a sphere or the standard approach mapping mouse displacements as rotations around camera's axes.
75 lines
2.5 KiB
C++
75 lines
2.5 KiB
C++
// This file is part of Eigen, a lightweight C++ template library
|
|
// for linear algebra. Eigen itself is part of the KDE project.
|
|
//
|
|
// Copyright (C) 2008 Gael Guennebaud <g.gael@free.fr>
|
|
//
|
|
// Eigen is free software; you can redistribute it and/or
|
|
// modify it under the terms of the GNU Lesser General Public
|
|
// License as published by the Free Software Foundation; either
|
|
// version 3 of the License, or (at your option) any later version.
|
|
//
|
|
// Alternatively, you can redistribute it and/or
|
|
// modify it under the terms of the GNU General Public License as
|
|
// published by the Free Software Foundation; either version 2 of
|
|
// the License, or (at your option) any later version.
|
|
//
|
|
// Eigen is distributed in the hope that it will be useful, but WITHOUT ANY
|
|
// WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
|
|
// FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License or the
|
|
// GNU General Public License for more details.
|
|
//
|
|
// You should have received a copy of the GNU Lesser General Public
|
|
// License and a copy of the GNU General Public License along with
|
|
// Eigen. If not, see <http://www.gnu.org/licenses/>.
|
|
|
|
#include "trackball.h"
|
|
#include "camera.h"
|
|
|
|
using namespace Eigen;
|
|
|
|
void Trackball::track(const Vector2i& point2D)
|
|
{
|
|
if (mpCamera==0)
|
|
return;
|
|
Vector3f newPoint3D;
|
|
bool newPointOk = mapToSphere(point2D, newPoint3D);
|
|
|
|
if (mLastPointOk && newPointOk)
|
|
{
|
|
Vector3f axis = mLastPoint3D.cross(newPoint3D).normalized();
|
|
float cos_angle = mLastPoint3D.dot(newPoint3D);
|
|
if ( ei_abs(cos_angle) < 1.0 )
|
|
{
|
|
float angle = 2. * acos(cos_angle);
|
|
if (mMode==Around)
|
|
mpCamera->rotateAroundTarget(Quaternionf(AngleAxisf(angle, axis)));
|
|
else
|
|
mpCamera->localRotate(Quaternionf(AngleAxisf(-angle, axis)));
|
|
}
|
|
}
|
|
|
|
mLastPoint3D = newPoint3D;
|
|
mLastPointOk = newPointOk;
|
|
}
|
|
|
|
bool Trackball::mapToSphere(const Vector2i& p2, Vector3f& v3)
|
|
{
|
|
if ((p2.x() >= 0) && (p2.x() <= int(mpCamera->vpWidth())) &&
|
|
(p2.y() >= 0) && (p2.y() <= int(mpCamera->vpHeight())) )
|
|
{
|
|
double x = (double)(p2.x() - 0.5*mpCamera->vpWidth()) / (double)mpCamera->vpWidth();
|
|
double y = (double)(0.5*mpCamera->vpHeight() - p2.y()) / (double)mpCamera->vpHeight();
|
|
double sinx = sin(M_PI * x * 0.5);
|
|
double siny = sin(M_PI * y * 0.5);
|
|
double sinx2siny2 = sinx * sinx + siny * siny;
|
|
|
|
v3.x() = sinx;
|
|
v3.y() = siny;
|
|
v3.z() = sinx2siny2 < 1.0 ? sqrt(1.0 - sinx2siny2) : 0.0;
|
|
|
|
return true;
|
|
}
|
|
else
|
|
return false;
|
|
}
|