Method CalculateBoxPosition

trinity/Curves/Tr2FollowCurveKey.cpp:202–248

This function finds the place between two cones where xy object bounds can be placed. It sets two variables: - one how far down the view vector the front of the bounds are offset - one how far away from the view vector the bounds are offset Then it calculates the box position based on those variables */

	Then it calculates the box position based on those variables
*/
void Tr2CameraFollowCurveKey::CalculateBoxPosition()
{
	auto rotMatrix = Tr2Renderer::GetInverseViewTransform();
	m_fov = Tr2Renderer::GetFieldOfView() * 0.5f;
	m_frontClip = Tr2Renderer::GetFrontClip();

	if( !m_enabled )
	{
		rotMatrix = m_lastEnabledInverseViewMatrix;
		m_fov = m_lastEnabledFOV;
		m_frontClip = m_lastEnabledFrontClip;
	}


	float tanOuterFov = tan( m_fov );
	float tanInnerFov = tan( m_fov * m_fovMultiplication );

	float nearClipPlaneSize = m_frontClip / tanOuterFov;
	float aspectRatio = Tr2Renderer::GetAspectRatio();

	float nearClipDistFromViewVector = max( nearClipPlaneSize * aspectRatio, nearClipPlaneSize / aspectRatio );
	float radius = max( Length( m_objectBounds.GetXY() ), nearClipDistFromViewVector );

	if( tanInnerFov == tanOuterFov )
	{
		m_minDistanceFromViewAngle = 0;
		m_minDistanceAlongViewAngle = 0;
		return;
	}

	m_minDistanceAlongViewAngle = 2.0f * radius / ( tanOuterFov - tanInnerFov );
	m_minDistanceFromViewAngle = m_minDistanceAlongViewAngle * tanInnerFov;
	if( m_minDistanceAlongViewAngle < m_frontClip + m_objectBounds.z )
	{
		m_minDistanceAlongViewAngle = m_frontClip + m_objectBounds.z;
		m_minDistanceFromViewAngle = m_minDistanceAlongViewAngle * tanInnerFov;
	}

	auto boxCenter = Vector3( 0, 0, -m_minDistanceAlongViewAngle - m_objectBounds.z ) + m_offset * Vector3( 1, 1, -1 );
	auto orientationMatrix = RotationMatrix( RotationQuaternion( Vector3( 0, 0, -1 ), m_angle + m_angleZero ) );

	auto boxOffsetXY = TransformCoord( Vector3( radius + m_minDistanceFromViewAngle, 0, 0 ), orientationMatrix );

	m_rotatedLeftTangent = TransformCoord( m_leftTangent, rotMatrix );
	m_rotatedRightTangent = TransformCoord( m_rightTangent, rotMatrix );
	m_boxPosition = TransformCoord( boxOffsetXY + boxCenter, rotMatrix );
}

Vector3 Tr2CameraFollowCurveKey::GetValue()
{