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50
51#include "camera.h"
52
53Camera::Camera(const QVector3D &pos)
54 : m_forward(0.0f, 0.0f, -1.0f),
55 m_right(1.0f, 0.0f, 0.0f),
56 m_up(0.0f, 1.0f, 0.0f),
57 m_pos(pos),
58 m_yaw(0.0f),
59 m_pitch(0.0f)
60{
61}
62
63static inline void clamp360(float *v)
64{
65 if (*v > 360.0f)
66 *v -= 360.0f;
67 if (*v < -360.0f)
68 *v += 360.0f;
69}
70
71void Camera::yaw(float degrees)
72{
73 m_yaw += degrees;
74 clamp360(&m_yaw);
75 m_yawMatrix.setToIdentity();
76 m_yawMatrix.rotate(m_yaw, 0, 1, 0);
77
78 QMatrix4x4 rotMat = m_pitchMatrix * m_yawMatrix;
79 m_forward = (QVector4D(0.0f, 0.0f, -1.0f, 0.0f) * rotMat).toVector3D();
80 m_right = (QVector4D(1.0f, 0.0f, 0.0f, 0.0f) * rotMat).toVector3D();
81}
82
83void Camera::pitch(float degrees)
84{
85 m_pitch += degrees;
86 clamp360(&m_pitch);
87 m_pitchMatrix.setToIdentity();
88 m_pitchMatrix.rotate(m_pitch, 1, 0, 0);
89
90 QMatrix4x4 rotMat = m_pitchMatrix * m_yawMatrix;
91 m_forward = (QVector4D(0.0f, 0.0f, -1.0f, 0.0f) * rotMat).toVector3D();
92 m_up = (QVector4D(0.0f, 1.0f, 0.0f, 0.0f) * rotMat).toVector3D();
93}
94
95void Camera::walk(float amount)
96{
97 m_pos[0] += amount * m_forward.x();
98 m_pos[2] += amount * m_forward.z();
99}
100
101void Camera::strafe(float amount)
102{
103 m_pos[0] += amount * m_right.x();
104 m_pos[2] += amount * m_right.z();
105}
106
107QMatrix4x4 Camera::viewMatrix() const
108{
109 QMatrix4x4 m = m_pitchMatrix * m_yawMatrix;
110 m.translate(-m_pos);
111 return m;
112}
113