void CM_TraceThroughTerrain( traceWork_t *tw, trace_t &trace, cbrush_t *brush )
{
CCMLandScape *landscape;
vec3_t tBegin, tEnd, tDistance, tStep;
vec3_t baseStart;
vec3_t baseEnd;
int count;
int i;
float fraction;
// At this point we know we may be colliding with a terrain brush (and we know we have a valid terrain structure)
landscape = cmg.landScape;
if (!landscape)
{
assert(landscape);
Com_Error(ERR_FATAL,"Brush had surfaceparm terrain, but there is no Terrain entity on this map!");
}
// Check for absolutely no connection
if(!CM_GenericBoxCollide(tw->bounds, landscape->GetBounds()))
{
return;
}
// Now we know that at least some part of the trace needs to collide with the terrain
// The regular brush collision is handled elsewhere, so advance the ray to an edge in the terrain brush
CM_TraceThroughBrush( tw, trace, brush, true );
// Remember the base entering and leaving fractions
tw->baseEnterFrac = tw->enterFrac;
tw->baseLeaveFrac = tw->leaveFrac;
// Reset to full spread within the brush
tw->enterFrac = -1.0f;
tw->leaveFrac = 1.0f;
// Work out the corners of the AABB when the trace first hits the terrain brush and when it leaves
VectorAdvance(tw->start, tw->baseEnterFrac, tw->end, tBegin);
VectorAdvance(tw->start, tw->baseLeaveFrac, tw->end, tEnd);
VectorSubtract(tEnd, tBegin, tDistance);
// Calculate number of iterations to process
count = ceilf(VectorLength(tDistance) / (landscape->GetPatchScalarSize() * TERRAIN_STEP_MAGIC));
count = 1;
fraction = trace.fraction;
VectorScale(tDistance, 1.0f / count, tStep);
// Save the base start and end vectors
VectorCopy ( tw->start, baseStart );
VectorCopy ( tw->end, baseEnd );
// Use the terrain vectors. Start both at the beginning since the
// step will be added to the end as the first step of the loop
VectorCopy ( tBegin, tw->start );
VectorCopy ( tBegin, tw->end );
// Step thru terrain patches moving on about 1 patch at a time
for ( i = 0; i < count; i ++ )
{
// Add the step to the end
VectorAdd(tw->end, tStep, tw->end);
CM_CalcExtents(tBegin, tw->end, tw, tw->localBounds);
landscape->PatchCollide(tw, trace, tw->start, tw->end, brush->checkcount);
// If collision with something closer than water then just stop here
if ( trace.fraction < fraction )
{
// Convert the fraction of this sub tract into the full trace's fraction
trace.fraction = i * (1.0f / count) + (1.0f / count) * trace.fraction;
break;
}
// Move the end to the start so the next trace starts
// where this one left off
VectorCopy(tw->end, tw->start);
}
// Put the original start and end back
VectorCopy ( baseStart, tw->start );
VectorCopy ( baseEnd, tw->end );
// Convert to global fraction only if something was hit along the way
if ( trace.fraction != 1.0 )
{
trace.fraction = tw->baseEnterFrac + ((tw->baseLeaveFrac - tw->baseEnterFrac) * trace.fraction);
trace.contents = brush->contents;
}
// Collide with any water
if ( tw->contents & CONTENTS_WATER )
{
fraction = landscape->WaterCollide(tw->start, tw->end, trace.fraction);
if( fraction < trace.fraction )
{
VectorSet(trace.plane.normal, 0.0f, 0.0f, 1.0f);
trace.contents = landscape->GetWaterContents();
trace.fraction = fraction;
trace.surfaceFlags = landscape->GetWaterSurfaceFlags();
}
}
}
void CM_TraceThroughTerrain( traceWork_t *tw, trace_t &trace, CCMLandScape *landscape)
{
vec3_t tBegin, tEnd, tDistance, tStep;
vec3_t baseStart;
vec3_t baseEnd;
int count;
int i;
float fraction;
// Check for absolutely no connection
if(!CM_GenericBoxCollide(tw->bounds, landscape->GetBounds()))
{
return;
}
tw->enterFrac = 0.0f;
tw->leaveFrac = 1.0f;
tw->clipplane = NULL;
tw->getout = false;
tw->startout = false;
tw->leadside = NULL;
// Remember the base entering and leaving fractions
tw->baseEnterFrac = tw->enterFrac;
tw->baseLeaveFrac = tw->leaveFrac;
// Reset to full spread within the brush
tw->enterFrac = -1.0f;
tw->leaveFrac = 1.0f;
// Work out the corners of the AABB when the trace first hits the terrain brush and when it leaves
VectorAdvance(tw->start, tw->baseEnterFrac, tw->end, tBegin);
VectorAdvance(tw->start, tw->baseLeaveFrac, tw->end, tEnd);
VectorSubtract(tEnd, tBegin, tDistance);
// Calculate number of iterations to process
count = ceilf(VectorLength(tDistance) / (landscape->GetPatchScalarSize() * TERRAIN_STEP_MAGIC));
count = 1;
fraction = trace.fraction;
VectorScale(tDistance, 1.0f / count, tStep);
// Save the base start and end vectors
VectorCopy ( tw->start, baseStart );
VectorCopy ( tw->end, baseEnd );
// Use the terrain vectors. Start both at the beginning since the
// step will be added to the end as the first step of the loop
VectorCopy ( tBegin, tw->start );
VectorCopy ( tBegin, tw->end );
// Step thru terrain patches moving on about 1 patch at a time
for ( i = 0; i < count; i ++ )
{
// Add the step to the end
VectorAdd(tw->end, tStep, tw->end);
CM_CalcExtents(tBegin, tw->end, tw, tw->localBounds);
landscape->PatchCollide(tw, trace, tw->start, tw->end, cmg.checkcount);
// If collision with something closer than water then just stop here
if ( trace.fraction < fraction )
{
// Convert the fraction of this sub tract into the full trace's fraction
trace.fraction = i * (1.0f / count) + (1.0f / count) * trace.fraction;
break;
}
// Move the end to the start so the next trace starts
// where this one left off
VectorCopy(tw->end, tw->start);
}
// Put the original start and end back
VectorCopy ( baseStart, tw->start );
VectorCopy ( baseEnd, tw->end );
// Convert to global fraction only if something was hit along the way
if ( trace.fraction != 1.0 )
{
// trace.fraction = tw->baseEnterFrac + ((tw->baseLeaveFrac - tw->baseEnterFrac) * trace.fraction);
trace.contents = CONTENTS_TERRAIN | CONTENTS_OUTSIDE;
}
// Collide with any water
if ( tw->contents & CONTENTS_WATER )
{
fraction = landscape->WaterCollide(tw->start, tw->end, trace.fraction);
if( fraction < trace.fraction )
{
VectorSet(trace.plane.normal, 0.0f, 0.0f, 1.0f);
trace.contents = landscape->GetWaterContents();
trace.fraction = fraction;
trace.surfaceFlags = landscape->GetWaterSurfaceFlags();
}
}
}
