BOOL LLVOSurfacePatch::lineSegmentIntersect(const LLVector4a& start, const LLVector4a& end, S32 face, BOOL pick_transparent, S32 *face_hitp,
LLVector4a* intersection,LLVector2* tex_coord, LLVector4a* normal, LLVector4a* tangent)
{
if (!lineSegmentBoundingBox(start, end))
{
return FALSE;
}
LLVector4a da;
da.setSub(end, start);
LLVector3 delta(da.getF32ptr());
LLVector3 pdelta = delta;
pdelta.mV[2] = 0;
F32 plength = pdelta.length();
F32 tdelta = 1.f/plength;
LLVector3 v_start(start.getF32ptr());
LLVector3 origin = v_start - mRegionp->getOriginAgent();
if (mRegionp->getLandHeightRegion(origin) > origin.mV[2])
{
//origin is under ground, treat as no intersection
return FALSE;
}
//step one meter at a time until intersection point found
//VECTORIZE THIS
const LLVector4a* exta = mDrawable->getSpatialExtents();
LLVector3 ext[2];
ext[0].set(exta[0].getF32ptr());
ext[1].set(exta[1].getF32ptr());
F32 rad = (delta*tdelta).magVecSquared();
F32 t = 0.f;
while ( t <= 1.f)
{
LLVector3 sample = origin + delta*t;
if (AABBSphereIntersectR2(ext[0], ext[1], sample+mRegionp->getOriginAgent(), rad))
{
F32 height = mRegionp->getLandHeightRegion(sample);
if (height > sample.mV[2])
{ //ray went below ground, positive intersection
//quick and dirty binary search to get impact point
tdelta = -tdelta*0.5f;
F32 err_dist = 0.001f;
F32 dist = fabsf(sample.mV[2] - height);
while (dist > err_dist && tdelta*tdelta > 0.0f)
{
t += tdelta;
sample = origin+delta*t;
height = mRegionp->getLandHeightRegion(sample);
if ((tdelta < 0 && height < sample.mV[2]) ||
(height > sample.mV[2] && tdelta > 0))
{ //jumped over intersection point, go back
tdelta = -tdelta;
}
tdelta *= 0.5f;
dist = fabsf(sample.mV[2] - height);
}
if (intersection)
{
F32 height = mRegionp->getLandHeightRegion(sample);
if (fabsf(sample.mV[2]-height) < delta.length()*tdelta)
{
sample.mV[2] = mRegionp->getLandHeightRegion(sample);
}
intersection->load3((sample + mRegionp->getOriginAgent()).mV);
}
if (normal)
{
normal->load3((mRegionp->getLand().resolveNormalGlobal(mRegionp->getPosGlobalFromRegion(sample))).mV);
}
return TRUE;
}
}
t += tdelta;
if (t > 1 && t < 1.f+tdelta*0.99f)
{ //make sure end point is checked (saves vertical lines coming up negative)
t = 1.f;
}
}
return FALSE;
}
bool set_conditions(const std::vector<rib_data_type> &rbs, const std::vector<index_type> &maxd, bool cl=false)
{
index_type i, j, nsegs(static_cast<index_type>(maxd.size())), nribs(rbs.size());
// ensure input vectors are correct size
if (!cl && (nribs!=(nsegs+1)))
return false;
if (cl && (nribs!=nsegs))
return false;
// check to make sure have valid end conditions
if (!cl)
{
if (rbs[0].use_left_fp() || rbs[0].use_left_fpp() || rbs[0].get_continuity()!=rib_data_type::C0)
{
return false;
}
if (rbs[nsegs].use_right_fp() || rbs[nsegs].use_right_fpp() || rbs[nsegs].get_continuity()!=rib_data_type::C0)
{
return false;
}
}
// make sure ribs are in valid state
data_type v_start(rbs[0].get_t0()), v_end(rbs[0].get_tmax());
tolerance_type tol;
for (i=0; i<nribs; ++i)
{
if (!rbs[i].check_state())
return false;
if (!tol.approximately_equal(rbs[i].get_t0(), v_start) || !tol.approximately_equal(rbs[i].get_tmax(), v_end))
return false;
}
// find all unique v-coordinates on joints for each rib
auto comp = [&tol](const data_type &x1, const data_type &x2)->bool
{
return tol.approximately_less_than(x1, x2);
};
std::vector<data_type> joints;
data_type t0(rbs[0].get_t0()), tmax(rbs[0].get_tmax());
rbs[0].get_joints(std::back_inserter(joints));
for (i=1; i<nribs; ++i)
{
// test to make sure this rib's parameterization matches rest
if (!tol.approximately_equal(rbs[i].get_t0(), t0) || !tol.approximately_equal(rbs[i].get_tmax(), tmax))
{
return false;
}
// get the joints on the current rib
std::vector<data_type> rjoints, jts_out;
rbs[i].get_joints(std::back_inserter(rjoints));
// merge these joints with current list of joints
std::set_union(joints.begin(), joints.end(), rjoints.begin(), rjoints.end(), std::back_inserter(jts_out), comp);
std::swap(joints, jts_out);
}
// record where the joints need to be for create()
index_type njoints(static_cast<index_type>(joints.size()));
// set the v-parameterization
this->set_number_v_segments(njoints-1);
this->set_initial_v(joints[0]);
for (j=0; j<(njoints-1); ++j)
{
this->set_dv(joints[j+1]-joints[j], j);
}
// reset the number of u-segments
this->set_number_u_segments(nsegs);
ribs=rbs;
max_degree=maxd;
closed=cl;
return true;
}
