OrbitCamera.cpp

Go to the documentation of this file.

#include "OrbitCamera.h"
#include "glm/gtc/matrix_transform.hpp"
 
constexpr float CAMERA_DEFAULT_YAW = 0.0f;
constexpr float CAMERA_DEFAULT_PITCH = 90.0f;
constexpr float CAMERA_DEFAULT_RADIUS = 5.0f;
constexpr float CAMERA_MIN_RADIUS = 0.5f;
constexpr float CAMERA_MAX_RADIUS = 150.0f;
 
OrbitCamera::OrbitCamera()
    : pos_(glm::vec3(0.0f)),
      target_(glm::vec3(0.0f)),
      up_(glm::vec3(0.0f)),
      right_(glm::vec3(0.0f)),
      yaw_(0.0f),
      pitch_(0.0f),
      radius_(0.0f)
{
    reset();
}
 
glm::mat4 OrbitCamera::getViewMatrix() const
{
    return glm::lookAt(pos_, target_, up_);
}
 
void OrbitCamera::reset()
{
    pos_ = glm::vec3(0.0f, 0.0f, 0.0f);
    target_ = glm::vec3(0.0f, 0.0f, 0.0f);
    up_ = glm::vec3(0.0f, 0.0f, 1.0f);
    yaw_ = CAMERA_DEFAULT_YAW;
    pitch_ = CAMERA_DEFAULT_PITCH;
    radius_ = CAMERA_DEFAULT_RADIUS;
    updatePosition();
}
 
void OrbitCamera::resetFromBounds(float zMin, float zMax, float fovDegrees)
{
    reset();
 
    // by default, creatures/characters are "on the ground", consider 0 as minimal possible z value
    if (zMin < 0.0f)
        zMin = 0.0f;
 
    target_.z = (zMin + zMax) / 2.0f;
    setRadius((zMin + zMax) / 2.0f * 1.3f / sinf(glm::radians(fovDegrees / 2.0f)));
    updatePosition();
}
 
void OrbitCamera::setLookAt(const glm::vec3& target)
{
    target_ = target;
    updatePosition();
}
 
void OrbitCamera::setRadius(float radius)
{
    radius_ = glm::clamp(radius, CAMERA_MIN_RADIUS, CAMERA_MAX_RADIUS);
    updatePosition();
}
 
void OrbitCamera::setPosition(const glm::vec3& position)
{
    pos_ = position;
}
 
void OrbitCamera::setYawAndPitch(float yaw, float pitch)
{
    yaw_ = yaw;
 
    if (yaw_ > 360.0f)
        yaw_ -= 360.0f;
 
    if (yaw_ < 0.0)
        yaw_ = 360.0f - yaw_;
 
    setPitch(pitch);
    updatePosition();
}
 
void OrbitCamera::setYaw(float yaw)
{
    yaw_ = yaw;
    updatePosition();
}
 
void OrbitCamera::setPitch(float pitch)
{
    pitch_ = glm::clamp(pitch, CAMERA_DEFAULT_PITCH - 90.0f + 0.1f, CAMERA_DEFAULT_PITCH + 90.0f - 0.1f);
    updatePosition();
}
 
void OrbitCamera::updatePosition()
{
    pos_.x = target_.x + radius_ * sinf(glm::radians(pitch_)) * cosf(glm::radians(yaw_));
    pos_.y = target_.y + radius_ * sinf(glm::radians(pitch_)) * sinf(glm::radians(yaw_));
    pos_.z = target_.z + radius_ * cosf(glm::radians(pitch_));
    right_ = glm::normalize(glm::cross(target_ - pos_, up_));
}