Box2f scale( const Box2f& b, float sx, float sy, float xcenter, float ycenter)
{
Box2f box = offsetBy( b, V2f( -xcenter, -ycenter));
box = scale( box, sx, sy);
box = offsetBy( box, V2f( xcenter, ycenter));
return box;
}
Box2i scale( const Box2i& b, float sx, float sy, int xcenter, int ycenter)
{
Box2i box = offsetBy( b, V2i( -xcenter, -ycenter));
box = scale( box, sx, sy);
box = offsetBy( box, V2i( xcenter, ycenter));
return box;
}
void scroll( const Imath::V2i& inc)
{
if( y_down_)
world_ = offsetBy( world_, Imath::V2f( inc.x / zoom_x(), -inc.y / zoom_y()));
else
world_ = offsetBy( world_, Imath::V2f( inc.x / zoom_x(), inc.y / zoom_y()));
}
void zoom( const Imath::V2f& center, float xfactor, float yfactor)
{
world_ = offsetBy( world_, Imath::V2f( -center.x, -center.y));
world_.min.x *= xfactor;
world_.min.y *= yfactor;
world_.max.x *= xfactor;
world_.max.y *= yfactor;
world_ = offsetBy( world_, Imath::V2f( center.x, center.y));
}
void scroll_to_center_point( const Imath::V2f& center)
{
world_ = offsetBy( world_, center - world_.center());
}
