camera.cpp Example File

hellovulkancubes/camera.cpp
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 #include "camera.h"

 Camera::Camera(const QVector3D &pos)
     : m_forward(0.0f, 0.0f, -1.0f),
       m_right(1.0f, 0.0f, 0.0f),
       m_up(0.0f, 1.0f, 0.0f),
       m_pos(pos),
       m_yaw(0.0f),
       m_pitch(0.0f)
 {
 }

 static inline void clamp360(float *v)
 {
     if (*v > 360.0f)
         *v -= 360.0f;
     if (*v < -360.0f)
         *v += 360.0f;
 }

 void Camera::yaw(float degrees)
 {
     m_yaw += degrees;
     clamp360(&m_yaw);
     m_yawMatrix.setToIdentity();
     m_yawMatrix.rotate(m_yaw, 0, 1, 0);

     QMatrix4x4 rotMat = m_pitchMatrix * m_yawMatrix;
     m_forward = (QVector4D(0.0f, 0.0f, -1.0f, 0.0f) * rotMat).toVector3D();
     m_right = (QVector4D(1.0f, 0.0f, 0.0f, 0.0f) * rotMat).toVector3D();
 }

 void Camera::pitch(float degrees)
 {
     m_pitch += degrees;
     clamp360(&m_pitch);
     m_pitchMatrix.setToIdentity();
     m_pitchMatrix.rotate(m_pitch, 1, 0, 0);

     QMatrix4x4 rotMat = m_pitchMatrix * m_yawMatrix;
     m_forward = (QVector4D(0.0f, 0.0f, -1.0f, 0.0f) * rotMat).toVector3D();
     m_up = (QVector4D(0.0f, 1.0f, 0.0f, 0.0f) * rotMat).toVector3D();
 }

 void Camera::walk(float amount)
 {
     m_pos[0] += amount * m_forward.x();
     m_pos[2] += amount * m_forward.z();
 }

 void Camera::strafe(float amount)
 {
     m_pos[0] += amount * m_right.x();
     m_pos[2] += amount * m_right.z();
 }

 QMatrix4x4 Camera::viewMatrix() const
 {
     QMatrix4x4 m = m_pitchMatrix * m_yawMatrix;
     m.translate(-m_pos);
     return m;
 }