Use a slightly different approach to tree bound intersection (by Lynx3d)

--HG--
branch : trunk
This commit is contained in:
click
2010-07-15 19:43:47 +02:00
parent a214443409
commit d2b4ffbec3

View File

@@ -116,32 +116,36 @@ class BIH
template<typename RayCallback>
void intersectRay(const Ray &r, RayCallback& intersectCallback, float &maxDist, bool stopAtFirst=false) const
{
float intervalMin = 0.f;
float intervalMax = maxDist;
float intervalMin = -1.f;
float intervalMax = -1.f;
Vector3 org = r.origin();
Vector3 dir = r.direction();
Vector3 invDir;
float t1, t2;
for(int i=0; i<3; ++i)
for (int i=0; i<3; ++i)
{
invDir[i] = 1.f / dir[i];
t1 = (bounds.low()[i] - org[i]) * invDir[i];
t2 = (bounds.high()[i] - org[i]) * invDir[i];
if (invDir[i] > 0) {
if (dir[i] != 0.f)
{
float t1 = (bounds.low()[i] - org[i]) * invDir[i];
float t2 = (bounds.high()[i] - org[i]) * invDir[i];
if (t1 > t2)
std::swap(t1, t2);
if (t1 > intervalMin)
intervalMin = t1;
if (t2 < intervalMax)
if (t2 < intervalMax || intervalMax < 0.f)
intervalMax = t2;
} else {
if (t2 > intervalMin)
intervalMin = t2;
if (t1 < intervalMax)
intervalMax = t1;
// intervalMax can only become smaller for other axis,
// and intervalMin only larger respectively, so stop early
if (intervalMax <= 0 || intervalMin >= maxDist)
return;
}
if (intervalMin > intervalMax)
return;
}
if (intervalMin > intervalMax)
return;
intervalMin = std::max(intervalMin, 0.f);
intervalMax = std::min(intervalMax, maxDist);
uint32 offsetFront[3];
uint32 offsetBack[3];
uint32 offsetFront3[3];