bool AddSeg(seg_t *seg)
{
FGLSectionLine &line = SectionLines[SectionLines.Reserve(1)];
bool firstline = loop->numlines == 0;
if (ISDONE(seg-segs, processed_segs))
{
// should never happen!
DPrintf("Tried to add seg %d to Sections twice. Cannot create Sections.\n", seg-segs);
return false;
}
SETDONE(seg-segs, processed_segs);
section_for_segs[seg-segs] = Sections.Size()-1;
line.start = seg->v1;
line.end = seg->v2;
line.sidedef = seg->sidedef;
line.linedef = seg->linedef;
line.refseg = seg;
line.polysub = NULL;
line.otherside = -1;
if (loop->numlines == 0)
{
v1_l1 = seg->v1;
v2_l1 = seg->v2;
}
loop->numlines++;
return true;
}
//=============================================================================
//
// all segs and subsectors must be grouped into Sections
//
//=============================================================================
bool CheckSections()
{
bool res = true;
for (int i = 0; i < numsegs; i++)
{
if (segs[i].sidedef != NULL && !ISDONE(i, processed_segs) && !IntraSectorSeg(&segs[i]))
{
Printf("Seg %d (Linedef %d) not processed during section creation\n", i, segs[i].linedef-lines);
res = false;
}
}
for (int i = 0; i < numsubsectors; i++)
{
if (!ISDONE(i, processed_subsectors))
{
Printf("Subsector %d (Sector %d) not processed during section creation\n", i, subsectors[i].sector-sectors);
res = false;
}
}
return res;
}
//=============================================================================
//
//
//
//=============================================================================
bool CreateSections()
{
int pick = 0;
MarkInternalSubsectors();
while (pick < numsubsectors)
{
if (ISDONE(pick, processed_subsectors))
{
pick++;
continue;
}
subsector_t *subsector = &subsectors[pick];
seg_t *workseg = NULL;
vertex_t *startpt = NULL;
NewSection(subsector->render_sector);
while (1)
{
if (!ISDONE(subsector-subsectors, processed_subsectors))
{
SETDONE(subsector-subsectors, processed_subsectors);
section->subsectors.Push(subsector);
SectionForSubsector[subsector - subsectors] = int(section - &Sections[0]);
}
bool result = AddSubSector(subsector, startpt, &workseg);
if (!result)
{
return false; // couldn't create Sections
}
else if (workseg != NULL)
{
// crossing into another subsector
seg_t *partner = workseg->PartnerSeg;
if (workseg->v2 != partner->v1)
{
DPrintf("Inconsistent subsector references in seg %d. Cannot create Sections.\n", workseg-segs);
return false;
}
subsector = partner->Subsector;
startpt = workseg->v1;
}
else
{
// loop complete. Check adjoining subsectors for other loops to
// be added to this section
if (!FindNextSeg(&workseg))
{
return false;
}
else if (workseg == NULL)
{
// No more subsectors found. This section is complete!
FinalizeSection();
break;
}
else
{
subsector = workseg->Subsector;
// If this is a regular seg, start there, otherwise start
// at the subsector's first seg
startpt = workseg->sidedef == NULL? NULL : workseg->v1;
NewLoop();
}
}
}
}
if (!CheckSections()) return false;
SetReferences();
Sections.ShrinkToFit();
SectionLoops.ShrinkToFit();
SectionLines.ShrinkToFit();
tesselateSections();
return true;
}
//==========================================================================
//
// returns the seg whose partner seg determines where this
// section continues
//
//==========================================================================
bool AddSubSector(subsector_t *subsec, vertex_t *startpt, seg_t **pNextSeg)
{
unsigned i = 0;
if (startpt != NULL)
{
// find the seg in this subsector that starts at the given vertex
for(i = 0; i < subsec->numlines; i++)
{
if (subsec->firstline[i].v1 == startpt) break;
}
if (i == subsec->numlines)
{
DPrintf("Vertex not found in subsector %d. Cannot create Sections.\n", subsec-subsectors);
return false; // Nodes are bad
}
}
else
{
// Find the first unprocessed non-miniseg
for(i = 0; i < subsec->numlines; i++)
{
seg_t *seg = subsec->firstline + i;
if (seg->sidedef == NULL) continue;
if (IntraSectorSeg(seg)) continue;
if (ISDONE(seg-segs, processed_segs)) continue;
break;
}
if (i == subsec->numlines)
{
DPrintf("Unable to find a start seg. Cannot create Sections.\n");
return false; // Nodes are bad
}
startpt = subsec->firstline[i].v1;
}
seg_t *thisseg = subsec->firstline + i;
if (IntraSectorSeg(thisseg))
{
SETDONE(thisseg-segs, processed_segs);
// continue with the loop in the adjoining subsector
*pNextSeg = thisseg;
return true;
}
while(1)
{
if (loop->numlines > 0 && thisseg->v1 == v1_l1 && thisseg->v2 == v2_l1)
{
// This loop is complete
*pNextSeg = NULL;
return true;
}
if (!AddSeg(thisseg)) return NULL;
i = (i+1) % subsec->numlines;
seg_t *nextseg = subsec->firstline + i;
if (thisseg->v2 != nextseg->v1)
{
DPrintf("Segs in subsector %d are not continuous. Cannot create Sections.\n", subsec-subsectors);
return false; // Nodes are bad
}
if (IntraSectorSeg(nextseg))
{
SETDONE(nextseg-segs, processed_segs);
// continue with the loop in the adjoining subsector
*pNextSeg = nextseg;
return true;
}
thisseg = nextseg;
}
}