public bool TestIntersection(GeoAABB2 aabb)
{
if (mFlatTreeList == null || mFlatTreeList.Count == 0)
{
return(false);
}
int closer, other;
BVHTraversal[] todo = new BVHTraversal[64];
todo[0] = new BVHTraversal();
int stackptr = 0;
todo[stackptr].mIndex = 0;
todo[stackptr].mLength = -9999999.0f;
while (stackptr >= 0)
{
int ni = todo[stackptr].mIndex;
stackptr--;
BVHFlatNode2 node = mFlatTreeList[ni];
// 对叶节点做相交测试
if (node.mRightOffset == 0)
{
bool hit = false;
for (int o = 0; o < node.mLeafCount; ++o)
{
BVHObject2 obj = mBuildPrims[(int)node.mStartIndex + o];
hit = obj.TestAABBIntersect(aabb);
if (hit)
{
return(true);
}
}
}
else
{
closer = ni + 1;
other = ni + (int)node.mRightOffset;
// 对父结点做测试
bool hitc0 = GeoAABBUtils.IsAABBInsectAABB2(aabb.mMin, aabb.mMax, mFlatTreeList[closer].mBox.mMin, mFlatTreeList[closer].mBox.mMax);
bool hitc1 = GeoAABBUtils.IsAABBInsectAABB2(aabb.mMin, aabb.mMax, mFlatTreeList[other].mBox.mMin, mFlatTreeList[other].mBox.mMax);
if (hitc0 && hitc1)
{
todo[++stackptr] = new BVHTraversal(other, -9999);
todo[++stackptr] = new BVHTraversal(closer, -9999);
}
else if (hitc0)
{
todo[++stackptr] = new BVHTraversal(closer, -9999);
}
else if (hitc1)
{
todo[++stackptr] = new BVHTraversal(other, -9999);
}
}
}
return(false);
}
public bool GetIntersection(GeoRay2 ray, ref GeoInsectPointArrayInfo intersection, bool occlusion)
{
if (mFlatTreeList.Count == 0)
{
return(false);
}
intersection.mIsIntersect = false;
intersection.mLength = 999999999.0f;
intersection.mHitObject2 = null;
int closer, other;
BVHTraversal[] todo = new BVHTraversal[64];
todo[0] = new BVHTraversal();
int stackptr = 0;
todo[stackptr].mIndex = 0;
todo[stackptr].mLength = -9999999.0f;
while (stackptr >= 0)
{
int ni = todo[stackptr].mIndex;
float near = todo[stackptr].mLength;
stackptr--;
BVHFlatNode2 node = mFlatTreeList[ni];
// 对叶节点做相交测试
if (node.mRightOffset == 0)
{
bool hit = false;
for (int o = 0; o < node.mLeafCount; ++o)
{
GeoInsectPointArrayInfo current = new GeoInsectPointArrayInfo();
BVHObject2 obj = mBuildPrims[(int)node.mStartIndex + o];
hit = obj.IsIntersect(ref ray, ref current);
if (hit)
{
if (occlusion)
{
intersection = current;
return(true);
}
if (current.mLength < intersection.mLength)
{
intersection = current;
}
}
}
}
else
{
closer = ni + 1;
other = ni + (int)node.mRightOffset;
// 对父结点做测试
GeoInsectPointArrayInfo in1 = new GeoInsectPointArrayInfo();
GeoInsectPointArrayInfo in2 = new GeoInsectPointArrayInfo();
bool hitc0 = GeoRayUtils.IsRayInsectAABB2(ray.mOrigin, ray.mDirection, mFlatTreeList[closer].mBox.mMin, mFlatTreeList[closer].mBox.mMax, ref in1);
bool hitc1 = GeoRayUtils.IsRayInsectAABB2(ray.mOrigin, ray.mDirection, mFlatTreeList[other].mBox.mMin, mFlatTreeList[other].mBox.mMax, ref in2);
if (hitc0 && hitc1)
{
float l0 = (GeoUtils.ToVector2(in1.mHitGlobalPoint[0]) - ray.mOrigin).magnitude;
float l2 = (GeoUtils.ToVector2(in2.mHitGlobalPoint[0]) - ray.mOrigin).magnitude;
if (l2 < l0)
{
float temp = l0;
l0 = l2;
l2 = temp;
int itemp = closer;
closer = other;
other = itemp;
}
todo[++stackptr] = new BVHTraversal(other, l2);
todo[++stackptr] = new BVHTraversal(closer, l0);
}
else if (hitc0)
{
float l0 = (GeoUtils.ToVector2(in1.mHitGlobalPoint[0]) - ray.mOrigin).magnitude;
todo[++stackptr] = new BVHTraversal(closer, l0);
}
else if (hitc1)
{
float l2 = (GeoUtils.ToVector2(in2.mHitGlobalPoint[0]) - ray.mOrigin).magnitude;
todo[++stackptr] = new BVHTraversal(other, l2);
}
}
}
if (intersection.mHitObject2 != null)
{
intersection.mHitGlobalPoint.Clear();
intersection.mHitGlobalPoint.Add(ray.mOrigin + ray.mDirection * intersection.mLength);
}
return(intersection.mHitObject2 != null);
}
/// <summary>
///
/// </summary>
/// <param name="ray">射线</param>
/// <param name="intersection">交点信息</param>
/// <param name="occlusion">是否找到最短的。 true if 找到交叉就行； false if 找到最短的 </param>
/// <returns></returns>
public bool GetIntersection(BVHRay ray, ref BVHIntersectionInfo intersection, bool occlusion)
{
intersection.mLength = 999999999.0f;
intersection.mObject = null;
float[] bbhits = new float[4];
int closer, other;
BVHTraversal[] todo = new BVHTraversal[64];
todo[0] = new BVHTraversal();
int stackptr = 0;
todo[stackptr].mIndex = 0;
todo[stackptr].mLength = -9999999.0f;
while (stackptr >= 0)
{
int ni = todo[stackptr].mIndex;
float near = todo[stackptr].mLength;
stackptr--;
BVHFlatNode node = mFlatTreeList[ni];
// 对叶节点做相交测试
if (node.mRightOffset == 0)
{
bool hit = false;
for (int o = 0; o < node.mLeafCount; ++o)
{
BVHIntersectionInfo current = new BVHIntersectionInfo();
BVHObject obj = mBuildPrims[(int)node.mStartIndex + o];
hit = obj.GetIntersection(ref ray, ref current);
if (hit)
{
if (occlusion)
{
return(true);
}
if (current.mLength < intersection.mLength)
{
intersection = current;
}
}
}
}
else
{
// 对父结点做测试
bool hitc0 = mFlatTreeList[ni + 1].mBox.Intersect(ray, ref bbhits[0], ref bbhits[1]);
bool hitc1 = mFlatTreeList[ni + (int)node.mRightOffset].mBox.Intersect(ray, ref bbhits[2], ref bbhits[3]);
if (hitc0 && hitc1)
{
closer = ni + 1;
other = ni + (int)node.mRightOffset;
if (bbhits[2] < bbhits[0])
{
float temp = bbhits[0];
bbhits[0] = bbhits[2];
bbhits[2] = temp;
temp = bbhits[1];
bbhits[1] = bbhits[3];
bbhits[3] = temp;
int itemp = closer;
closer = other;
other = itemp;
}
todo[++stackptr] = new BVHTraversal(other, bbhits[2]);
todo[++stackptr] = new BVHTraversal(closer, bbhits[0]);
}
else if (hitc0)
{
todo[++stackptr] = new BVHTraversal(ni + 1, bbhits[0]);
}
else if (hitc1)
{
todo[++stackptr] = new BVHTraversal(ni + (int)node.mRightOffset, bbhits[2]);
}
}
}
if (intersection.mObject != null)
{
intersection.mHitPoint = ray.mOrigin + ray.mDirection * intersection.mLength;
}
return(intersection.mObject != null);
}