Camera.cpp

#include "Camera.h"
#include <glm/gtc/matrix_transform.hpp>

Camera::Camera(glm::vec3 position, glm::vec3 up, float yaw, float pitch)
        : front(glm::vec3(0.0f, 0.0f, -1.0f)), movementSpeed(SPEED), mouseSensitivity(SENSITIVITY), zoom(ZOOM) {
    this->position = position;
    this->worldUp = up;
    this->yaw = yaw;
    this->pitch = pitch;
    updateCameraVectors();
}

Camera::Camera(float posX, float posY, float posZ, float upX, float upY, float upZ, float yaw, float pitch) {
    this->position = glm::vec3(posX, posY, posZ);
    this->worldUp = glm::vec3(upX, upY, upZ);
    this->yaw = yaw;
    this->pitch = pitch;
    updateCameraVectors();
}

glm::mat4 Camera::GetViewMatrix() {
    return glm::lookAt(position, position + front, up);
}

void Camera::ProcessKeyboard(CameraMovement direction, float deltaTime) {
    float velocity = movementSpeed * deltaTime;
    if (direction == FORWARD)
        position += front * velocity;
    if (direction == BACKWARD)
        position -= front * velocity;
    if (direction == LEFT)
        position -= right * velocity;
    if (direction == RIGHT)
        position += right * velocity;
}

void Camera::ProcessMouseMovement(float xoffset, float yoffset, GLboolean constrainPitch) {
    xoffset *= mouseSensitivity;
    yoffset *= mouseSensitivity;

    yaw   += xoffset;
    pitch += yoffset;

    // make sure that when pitch is out of bounds, screen doesn't get flipped
    if (constrainPitch)
    {
        if (pitch > 89.0f)
            pitch = 89.0f;
        if (pitch < -89.0f)
            pitch = -89.0f;
    }

    // update Front, Right and Up Vectors using the updated Euler angles
    updateCameraVectors();
}

void Camera::ProcessMouseScroll(float yoffset) {
    zoom -= (float)yoffset;
    if (zoom < 1.0f)
        zoom = 1.0f;
    if (zoom > 45.0f)
        zoom = 45.0f;
}

void Camera::updateCameraVectors() {
    // calculate the new Front vector
    glm::vec3 front;
    front.x = cos(glm::radians(yaw)) * cos(glm::radians(pitch));
    front.y = sin(glm::radians(pitch));
    front.z = sin(glm::radians(yaw)) * cos(glm::radians(pitch));
    this->front = glm::normalize(front);
    // also re-calculate the Right and Up vector
    right = glm::normalize(glm::cross(this->front, worldUp));  // normalize the vectors, because their length gets closer to 0 the more you look up or down which results in slower movement.
    up    = glm::normalize(glm::cross(right, this->front));
}