+void GfxState::getUserClipBBox(double *xMin, double *yMin,
+ double *xMax, double *yMax) {
+ double ictm[6];
+ double xMin1, yMin1, xMax1, yMax1, det, tx, ty;
+
+ // invert the CTM
+ det = 1 / (ctm[0] * ctm[3] - ctm[1] * ctm[2]);
+ ictm[0] = ctm[3] * det;
+ ictm[1] = -ctm[1] * det;
+ ictm[2] = -ctm[2] * det;
+ ictm[3] = ctm[0] * det;
+ ictm[4] = (ctm[2] * ctm[5] - ctm[3] * ctm[4]) * det;
+ ictm[5] = (ctm[1] * ctm[4] - ctm[0] * ctm[5]) * det;
+
+ // transform all four corners of the clip bbox; find the min and max
+ // x and y values
+ xMin1 = xMax1 = clipXMin * ictm[0] + clipYMin * ictm[2] + ictm[4];
+ yMin1 = yMax1 = clipXMin * ictm[1] + clipYMin * ictm[3] + ictm[5];
+ tx = clipXMin * ictm[0] + clipYMax * ictm[2] + ictm[4];
+ ty = clipXMin * ictm[1] + clipYMax * ictm[3] + ictm[5];
+ if (tx < xMin1) {
+ xMin1 = tx;
+ } else if (tx > xMax1) {
+ xMax1 = tx;
+ }
+ if (ty < yMin1) {
+ yMin1 = ty;
+ } else if (ty > yMax1) {
+ yMax1 = ty;
+ }
+ tx = clipXMax * ictm[0] + clipYMin * ictm[2] + ictm[4];
+ ty = clipXMax * ictm[1] + clipYMin * ictm[3] + ictm[5];
+ if (tx < xMin1) {
+ xMin1 = tx;
+ } else if (tx > xMax1) {
+ xMax1 = tx;
+ }
+ if (ty < yMin1) {
+ yMin1 = ty;
+ } else if (ty > yMax1) {
+ yMax1 = ty;
+ }
+ tx = clipXMax * ictm[0] + clipYMax * ictm[2] + ictm[4];
+ ty = clipXMax * ictm[1] + clipYMax * ictm[3] + ictm[5];
+ if (tx < xMin1) {
+ xMin1 = tx;
+ } else if (tx > xMax1) {
+ xMax1 = tx;
+ }
+ if (ty < yMin1) {
+ yMin1 = ty;
+ } else if (ty > yMax1) {
+ yMax1 = ty;
+ }
+
+ *xMin = xMin1;
+ *yMin = yMin1;
+ *xMax = xMax1;
+ *yMax = yMax1;
+}
+