Method updateCameraFrameTime

source/camera/CameraManager.cpp:201–406

}

void CameraManager::updateCameraFrameTime(const Ogre::Real frameTime)
{
    if (!isCameraMovingAtAll())
        return;

    // Carry out the acceleration/deceleration calculations on the camera translation.
    Ogre::Real speed = mTranslateVector.normalise();
    mTranslateVector *= static_cast<Ogre::Real>(std::max(0.0, speed - (0.75 + (speed / MOVE_SPEED))
                        * MOVE_SPEED_ACCELERATION * frameTime));
    mTranslateVector += mTranslateVectorAccel * static_cast<Ogre::Real>(frameTime * 2.0);

    // If we have sped up to more than the maximum moveSpeed then rescale the
    // vector to that length. We use the squaredLength() in this calculation
    // since squaring the RHS is faster than sqrt'ing the LHS.
    if (mTranslateVector.squaredLength() > MOVE_SPEED * MOVE_SPEED)
    {
        speed = mTranslateVector.length();
        mTranslateVector *= MOVE_SPEED / speed;
    }

    // Get the camera's current position.
    Ogre::Vector3 newPosition =  getActiveCameraNode()->getPosition();

    // Get a quaternion which will rotate the "camera relative" x-y values
    // for the translateVector into the global x-y used to position the camera.
    Ogre::Vector3 viewTarget = getCameraViewTarget();

    Ogre::Vector3 viewDirection = viewTarget - newPosition;

    viewDirection.z = 0.0;

    Ogre::Quaternion viewDirectionQuaternion = Ogre::Vector3::UNIT_Y.getRotationTo(viewDirection);

    // Adjust the newPosition vector to account for the translation due
    // to the movement keys on the keyboard (the arrow keys and/or WASD).
    if (mZChange != 0)
    {
        newPosition.z += static_cast<Ogre::Real>(mZChange * frameTime * ZOOM_SPEED);
        // We also stow and stop the movement here, as the keyboard release events
        // and mouse wheel event are otherwise colliding on handling the zoom.
        if (mZChange > 0)
            mZChange -= MOVE_SPEED;
        else if (mZChange < 0)
            mZChange += MOVE_SPEED;
    }

    // Update the position for the other axices.
    newPosition += (viewDirectionQuaternion * mTranslateVector);

    // Prevent camera from moving down into the tiles or too high.
    if (newPosition.z <= MIN_CAMERA_Z)
        newPosition.z = MIN_CAMERA_Z;
    else if (newPosition.z >= MAX_CAMERA_Z)
        newPosition.z = MAX_CAMERA_Z;

    // Prevent the tilting to show a reversed world or looking too high.
    if (mRotateLocalVector.x != 0)
    {