// Intersect & push a new clip rectangle:
void Fl_Device::push_clip(int x, int y, int w, int h)
{
Region r;
if (w > 0 && h > 0)
{
fl_transform(x,y);
r = XRectangleRegion(x, y, w, h);
Region current = rstack[rstackptr];
if (current)
{
#ifndef _WIN32
Region temp = XCreateRegion();
XIntersectRegion(current, r, temp);
XDestroyRegion(r);
r = temp;
#else
CombineRgn(r,r,current,RGN_AND);
#endif
}
} // make empty clip region:
else
{
#ifndef _WIN32
r = XCreateRegion();
#else
r = CreateRectRgn(0,0,0,0);
#endif
}
if (rstackptr < STACK_MAX) rstack[++rstackptr] = r;
fl_restore_clip();
}
// Replace the top of the clip stack:
void fl_clip_region(Region r)
{
Region oldr = rstack[rstackptr];
if(oldr) XDestroyRegion(oldr);
rstack[rstackptr] = r;
fl_restore_clip();
}
// make there be no clip (used by fl_begin_offscreen() only!)
void Fl_Device::push_no_clip()
{
// this does not test maximum so that this is guaranteed to work,
// there is one extra slot at the top of the stack.
rstack[++rstackptr] = 0; /*if (rstackptr < STACK_MAX)*/
fl_restore_clip();
}
// pop back to previous clip:
void Fl_Device::pop_clip()
{
if (rstackptr > 0)
{
Region oldr = rstack[rstackptr--];
if (oldr) XDestroyRegion(oldr);
fl_restore_clip();
}
}
// Replace top of stack with top of stack minus this rectangle:
void Fl_Device::clip_out(int x, int y, int w, int h)
{
if (w <= 0 || h <= 0) return;
Region current = rstack[rstackptr];
// current must not be zero, you must push a rectangle first. I
// return without doing anything because that makes some old fltk code work:
if (!current) return;
fl_transform(x,y);
Region r = XRectangleRegion(x, y, w, h);
#ifndef _WIN32
Region temp = XCreateRegion();
XSubtractRegion(current, r, temp);
XDestroyRegion(r);
XDestroyRegion(current);
rstack[rstackptr] = temp;
#else
CombineRgn(current,current,r,RGN_DIFF);
DeleteObject(r);
#endif
fl_restore_clip();
}
FL_EXPORT_C(void,flc_restore_clip)( ){
fl_restore_clip();
}
