Updates the position and/or color of the object at the specified
depth, depth. The parameter
how determines what is updated.
how can either be the constant MOD_MATRIX
or MOD_COLOR or it can be a combination of both
(MOD_MATRIX|MOD_COLOR).
MOD_COLOR uses the current mulcolor (specified by the function
swf_mulcolor()) and addcolor (specified by the
function swf_addcolor()) to color the object.
MOD_MATRIX uses the current matrix to position the object.