+ if (p->desired_y < r->desired_y)
+ {
+ p->nrows = r->desired_vpos - p->desired_vpos;
+ p->height = r->desired_y - p->desired_y;
+ truncated_p = 1;
+ }
+ else
+ {
+ int nrows_copied = (r->desired_vpos + r->nrows
+ - p->desired_vpos);
+
+ if (p->nrows <= nrows_copied)
+ p->nrows = 0;
+ else
+ {
+ int height_copied = (r->desired_y + r->height
+ - p->desired_y);
+
+ p->current_vpos += nrows_copied;
+ p->desired_vpos += nrows_copied;
+ p->nrows -= nrows_copied;
+ p->current_y += height_copied;
+ p->desired_y += height_copied;
+ p->height -= height_copied;
+ truncated_p = 1;
+ }
+ }
+ }