摄像机

https://learnopengl-cn.github.io/01%20Getting%20started/09%20Camera/#_8

https://www.jianshu.com/p/003b1fb8d6d3

 

#include "ACamera.h"

#include <QDebug>

ACamera::ACamera(QVector3D position, QVector3D up, float yaw, float pitch) :
    position(position),
    worldUp(up),
    front(-position),
    picth(pitch),
    yaw(yaw),
    movementSpeed(SPEED),
    mouseSensitivity(SENSITIVITY),
    zoom(ZOOM)
{
    this->updateCameraVectors();

    for(uint i = 0; i != 1024; ++i)
        keys[i] = false;
}

ACamera::~ACamera()
{

}

// Returns the view matrix calculated using Euler Angles and the LookAt Matrix
QMatrix4x4 ACamera::getViewMatrix()
{
    QMatrix4x4 view;
    view.lookAt(this->position, this->position + this->front, this->up);
    return view;
}

// Processes input received from any keyboard-like input system. Accepts input parameter in the form of ACamera defined ENUM (to abstract it from windowing systems)
void ACamera::processKeyboard(Camera_Movement direction, float deltaTime)
{
    float velocity = this->movementSpeed * deltaTime;
    if (direction == FORWARD)
        this->position += this->front * velocity;
    if (direction == BACKWARD)
        this->position -= this->front * velocity;
    if (direction == LEFT)
        this->position += this->right * velocity;
    if (direction == RIGHT)
        this->position -= this->right * velocity;
    if (direction == UP)
        this->position += this->worldUp * velocity;
    if (direction == DOWN)
        this->position -= this->worldUp * velocity;
}

// Processes input received from a mouse input system. Expects the offset value in both the x and y direction.
void ACamera::processMouseMovement(float xoffset, float yoffset, bool constraintPitch)
{
  xoffset *= this->mouseSensitivity;
  yoffset *= this->mouseSensitivity;

  this->yaw += xoffset;
  this->picth += yoffset;

  if (constraintPitch) {
    if (this->picth > 89.0f)
      this->picth = 89.0f;
    if (this->picth < -89.0f)
      this->picth = -89.0f;
  }

  this->updateCameraVectors();
}

// Processes input received from a mouse scroll-wheel event. Only requires input on the vertical wheel-axis
void ACamera::processMouseScroll(float yoffset)
{
  if (this->zoom >= 1.0f && this->zoom <= 45.0f)
    this->zoom -= yoffset;
  if (this->zoom > 45.0f)
    this->zoom = 45.0f;
  if (this->zoom < 1.0f)
      this->zoom = 1.0f;
}

void ACamera::processInput(float dt)
{

    if (keys[Qt::Key_W])
      processKeyboard(FORWARD, dt);
    if (keys[Qt::Key_S])
      processKeyboard(BACKWARD, dt);
    if (keys[Qt::Key_A])
      processKeyboard(LEFT, dt);
    if (keys[Qt::Key_D])
      processKeyboard(RIGHT, dt);
    if (keys[Qt::Key_E])
      processKeyboard(UP, dt);
    if (keys[Qt::Key_Q])
      processKeyboard(DOWN, dt);
}

void ACamera::updateCameraVectors()
{
    // Calculate the new Front vector
    QVector3D front;
    front.setX(cos(this->yaw) * cos(this->picth));
    front.setY(sin(this->picth));
    front.setZ(sin(this->yaw) * cos(this->picth));
    this->front = front.normalized();
    this->right = QVector3D::crossProduct(this->front, this->worldUp).normalized();
    this->up = QVector3D::crossProduct(this->right, this->front).normalized();
}

ACamera.cpp