blob: 7c2da8e9655b4e0158994c344e26127f0d129764 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
|
// This file is part of Eigen, a lightweight C++ template library
// for linear algebra.
//
// Copyright (C) 2008 Gael Guennebaud <gael.guennebaud@inria.fr>
//
// 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/.
#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 ( std::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;
}
|
