+
+ /* the following code subtracts the upper left edge from all coordinates,
+ and set's posx,posy so that ST_PLACEOBJECT is used with a matrix.
+ Necessary for preprocessing with swfcombine. */
+ posx = xmin; posy = ymin;
+ p1.x-=posx;p2.x-=posx;p3.x-=posx;p4.x-=posx;
+ p1.y-=posy;p2.y-=posy;p3.y-=posy;p4.y-=posy;
+ xmin -= posx; ymin -= posy;
+ xmax -= posx; ymax -= posy;