static sraSpan *
sraSpanDup(const sraSpan *src) {
sraSpan *span;
if (!src) return NULL;
span = sraSpanCreate(src->start, src->end, src->subspan);
return span;
}
static sraSpan *
sraSpanDup(const sraSpan *src)
{
sraSpan *span;
if (IsBadReadPtr(src,sizeof(sraSpan))) return NULL;
span = sraSpanCreate(src->start, src->end, src->subspan);
return span;
}
sraRegion *
sraRgnCreateRect(int x1, int y1, int x2, int y2) {
sraSpanList *vlist, *hlist;
sraSpan *vspan, *hspan;
/* - Build the horizontal portion of the span */
hlist = sraSpanListCreate();
hspan = sraSpanCreate(x1, x2, NULL);
sraSpanInsertAfter(hspan, &(hlist->front));
/* - Build the vertical portion of the span */
vlist = sraSpanListCreate();
vspan = sraSpanCreate(y1, y2, hlist);
sraSpanInsertAfter(vspan, &(vlist->front));
sraSpanListDestroy(hlist);
return (sraRegion*)vlist;
}
static rfbBool
sraSpanListSubtract(sraSpanList *dest, const sraSpanList *src) {
sraSpan *d_curr, *s_curr;
if (!dest) {
if (!src) {
return 1;
} else {
printf("sraSpanListSubtract:incompatible spans (only one NULL!)\n");
return FALSE;
}
}
d_curr = dest->front._next;
s_curr = src->front._next;
while ((s_curr != &(src->back)) && (d_curr != &(dest->back))) {
/* - If we haven't reached a destination span yet then move on */
if (d_curr->start >= s_curr->end) {
s_curr = s_curr->_next;
continue;
}
/* - If we are beyond the current destination span then skip it */
if (d_curr->end <= s_curr->start) {
d_curr = d_curr->_next;
continue;
}
/* - If we partially overlap the current span then split it up */
if (s_curr->start > d_curr->start) {
sraSpanInsertBefore(sraSpanCreate(d_curr->start,
s_curr->start,
d_curr->subspan),
d_curr);
d_curr->start = s_curr->start;
}
if (s_curr->end < d_curr->end) {
sraSpanInsertAfter(sraSpanCreate(s_curr->end,
d_curr->end,
d_curr->subspan),
d_curr);
d_curr->end = s_curr->end;
}
/* - Now recursively process the affected span */
if ((!d_curr->subspan) || !sraSpanListSubtract(d_curr->subspan, s_curr->subspan)) {
/* - The destination subspan is now empty, so we should remove it */
sraSpan *next = d_curr->_next;
sraSpanRemove(d_curr);
sraSpanDestroy(d_curr);
d_curr = next;
} else {
/* Merge this span with previous or next? */
if (d_curr->_prev != &(dest->front))
sraSpanMergePrevious(d_curr);
if (d_curr->_next != &(dest->back))
sraSpanMergeNext(d_curr);
/* - Move on to the next span */
if (s_curr->end > d_curr->end) {
d_curr = d_curr->_next;
} else {
s_curr = s_curr->_next;
}
}
}
return !sraSpanListEmpty(dest);
}
static void
sraSpanListOr(sraSpanList *dest, const sraSpanList *src) {
sraSpan *d_curr, *s_curr;
int s_start, s_end;
if (!dest) {
if (!src) {
return;
} else {
printf("sraSpanListOr:incompatible spans (only one NULL!)\n");
return;
}
}
d_curr = dest->front._next;
s_curr = src->front._next;
s_start = s_curr->start;
s_end = s_curr->end;
while (s_curr != &(src->back)) {
/* - If we are at end of destination list OR
If the new span comes before the next destination one */
if ((d_curr == &(dest->back)) ||
(d_curr->start >= s_end)) {
/* - Add the span */
sraSpanInsertBefore(sraSpanCreate(s_start, s_end,
s_curr->subspan),
d_curr);
if (d_curr != &(dest->back))
sraSpanMergePrevious(d_curr);
s_curr = s_curr->_next;
s_start = s_curr->start;
s_end = s_curr->end;
} else {
/* - If the new span overlaps the existing one */
if ((s_start < d_curr->end) &&
(s_end > d_curr->start)) {
/* - Insert new span before the existing destination one? */
if (s_start < d_curr->start) {
sraSpanInsertBefore(sraSpanCreate(s_start,
d_curr->start,
s_curr->subspan),
d_curr);
sraSpanMergePrevious(d_curr);
}
/* Split the existing span if necessary */
if (s_end < d_curr->end) {
sraSpanInsertAfter(sraSpanCreate(s_end,
d_curr->end,
d_curr->subspan),
d_curr);
d_curr->end = s_end;
}
if (s_start > d_curr->start) {
sraSpanInsertBefore(sraSpanCreate(d_curr->start,
s_start,
d_curr->subspan),
d_curr);
d_curr->start = s_start;
}
/* Recursively OR subspans */
sraSpanListOr(d_curr->subspan, s_curr->subspan);
/* Merge this span with previous or next? */
if (d_curr->_prev != &(dest->front))
sraSpanMergePrevious(d_curr);
if (d_curr->_next != &(dest->back))
sraSpanMergeNext(d_curr);
/* Move onto the next pair to compare */
if (s_end > d_curr->end) {
s_start = d_curr->end;
d_curr = d_curr->_next;
} else {
s_curr = s_curr->_next;
s_start = s_curr->start;
s_end = s_curr->end;
}
} else {
/* - No overlap. Move to the next destination span */
d_curr = d_curr->_next;
}
}
}
}
static rfbBool
sraSpanListAnd(sraSpanList *dest, const sraSpanList *src)
{
sraSpan *d_curr, *s_curr, *d_next;
if (!dest)
{
if (!src)
{
return 1;
}
else
{
///rfbErr("sraSpanListAnd:incompatible spans (only one NULL!)\n");
return FALSE;
}
}
else if (!src)
return FALSE;
d_curr = dest->front._next;
s_curr = src->front._next;
while ((s_curr != &(src->back)) && (d_curr != &(dest->back)))
{
/* - If we haven't reached a destination span yet then move on */
if (d_curr->start >= s_curr->end)
{
s_curr = s_curr->_next;
continue;
}
/* - If we are beyond the current destination span then remove it */
if (d_curr->end <= s_curr->start)
{
sraSpan *next = d_curr->_next;
sraSpanRemove(d_curr);
sraSpanDestroy(d_curr);
d_curr = next;
continue;
}
/* - If we partially overlap a span then split it up or remove bits */
if (s_curr->start > d_curr->start)
{
/* - The top bit of the span does not match */
d_curr->start = s_curr->start;
}
if (s_curr->end < d_curr->end)
{
/* - The end of the span does not match */
sraSpanInsertAfter(sraSpanCreate(s_curr->end,
d_curr->end,
d_curr->subspan),
d_curr);
d_curr->end = s_curr->end;
}
/* - Now recursively process the affected span */
if (!sraSpanListAnd(d_curr->subspan, s_curr->subspan))
{
/* - The destination subspan is now empty, so we should remove it */
sraSpan *next = d_curr->_next;
sraSpanRemove(d_curr);
sraSpanDestroy(d_curr);
d_curr = next;
}
else
{
/* Merge this span with previous or next? */
if (d_curr->_prev != &(dest->front))
sraSpanMergePrevious(d_curr);
/* - Move on to the next span */
d_next = d_curr;
if (s_curr->end >= d_curr->end)
{
d_next = d_curr->_next;
}
if (s_curr->end <= d_curr->end)
{
s_curr = s_curr->_next;
}
d_curr = d_next;
}
}
while (d_curr != &(dest->back))
{
sraSpan *next = d_curr->_next;
sraSpanRemove(d_curr);
sraSpanDestroy(d_curr);
d_curr=next;
}
return !sraSpanListEmpty(dest);
}
