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-rw-r--r--indra/llmath/llvolume.cpp224
1 files changed, 45 insertions, 179 deletions
diff --git a/indra/llmath/llvolume.cpp b/indra/llmath/llvolume.cpp
index 242b0809eb..3b01140e3a 100644
--- a/indra/llmath/llvolume.cpp
+++ b/indra/llmath/llvolume.cpp
@@ -104,128 +104,46 @@ BOOL check_same_clock_dir( const LLVector3& pt1, const LLVector3& pt2, const LLV
}
}
-BOOL LLLineSegmentBoxIntersect(const LLVector3& start, const LLVector3& end, const LLVector3& center, const LLVector3& size)
+// intersect test between triangle pt1,pt2,pt3 and line from linept to linept+vect
+//returns TRUE if intersecting and moves linept to the point of intersection
+BOOL LLTriangleLineSegmentIntersect( const LLVector3& pt1, const LLVector3& pt2, const LLVector3& pt3, LLVector3& linept, const LLVector3& vect)
{
- float fAWdU[3];
- LLVector3 dir;
- LLVector3 diff;
-
- for (U32 i = 0; i < 3; i++)
- {
- dir.mV[i] = 0.5f * (end.mV[i] - start.mV[i]);
- diff.mV[i] = (0.5f * (end.mV[i] + start.mV[i])) - center.mV[i];
- fAWdU[i] = fabsf(dir.mV[i]);
- if(fabsf(diff.mV[i])>size.mV[i] + fAWdU[i]) return false;
- }
-
- float f;
- f = dir.mV[1] * diff.mV[2] - dir.mV[2] * diff.mV[1]; if(fabsf(f)>size.mV[1]*fAWdU[2] + size.mV[2]*fAWdU[1]) return false;
- f = dir.mV[2] * diff.mV[0] - dir.mV[0] * diff.mV[2]; if(fabsf(f)>size.mV[0]*fAWdU[2] + size.mV[2]*fAWdU[0]) return false;
- f = dir.mV[0] * diff.mV[1] - dir.mV[1] * diff.mV[0]; if(fabsf(f)>size.mV[0]*fAWdU[1] + size.mV[1]*fAWdU[0]) return false;
+ LLVector3 V1 = pt2-pt1;
+ LLVector3 V2 = pt3-pt2;
- return true;
-}
-
-
-// intersect test between triangle vert0, vert1, vert2 and a ray from orig in direction dir.
-// returns TRUE if intersecting and returns barycentric coordinates in intersection_a, intersection_b,
-// and returns the intersection point along dir in intersection_t.
-
-// Moller-Trumbore algorithm
-BOOL LLTriangleRayIntersect(const LLVector3& vert0, const LLVector3& vert1, const LLVector3& vert2, const LLVector3& orig, const LLVector3& dir,
- F32* intersection_a, F32* intersection_b, F32* intersection_t, BOOL two_sided)
-{
- F32 u, v, t;
-
- /* find vectors for two edges sharing vert0 */
- LLVector3 edge1 = vert1 - vert0;
-
- LLVector3 edge2 = vert2 - vert0;;
-
- /* begin calculating determinant - also used to calculate U parameter */
- LLVector3 pvec = dir % edge2;
+ LLVector3 norm = V1 % V2;
- /* if determinant is near zero, ray lies in plane of triangle */
- F32 det = edge1 * pvec;
+ F32 dotprod = norm * vect;
- if (!two_sided)
+ if(dotprod < 0)
{
- if (det < F_APPROXIMATELY_ZERO)
- {
- return FALSE;
- }
-
- /* calculate distance from vert0 to ray origin */
- LLVector3 tvec = orig - vert0;
+ //Find point of intersect to triangle plane.
+ //find t to intersect point
+ F32 t = -(norm * (linept-pt1))/dotprod;
- /* calculate U parameter and test bounds */
- u = tvec * pvec;
-
- if (u < 0.f || u > det)
+ // if ds is neg line started past triangle so can't hit triangle.
+ if (t > 0)
{
return FALSE;
}
- /* prepare to test V parameter */
- LLVector3 qvec = tvec % edge1;
+ LLVector3 pt_int = linept + (vect*t);
- /* calculate V parameter and test bounds */
- v = dir * qvec;
- if (v < 0.f || u + v > det)
+ if(check_same_clock_dir(pt1, pt2, pt_int, norm))
{
- return FALSE;
- }
-
- /* calculate t, scale parameters, ray intersects triangle */
- t = edge2 * qvec;
- F32 inv_det = 1.0 / det;
- t *= inv_det;
- u *= inv_det;
- v *= inv_det;
- }
-
- else // two sided
+ if(check_same_clock_dir(pt2, pt3, pt_int, norm))
{
- if (det > -F_APPROXIMATELY_ZERO && det < F_APPROXIMATELY_ZERO)
+ if(check_same_clock_dir(pt3, pt1, pt_int, norm))
{
- return FALSE;
+ // answer in pt_int is insde triangle
+ linept.setVec(pt_int);
+ return TRUE;
}
- F32 inv_det = 1.0 / det;
-
- /* calculate distance from vert0 to ray origin */
- LLVector3 tvec = orig - vert0;
-
- /* calculate U parameter and test bounds */
- u = (tvec * pvec) * inv_det;
- if (u < 0.f || u > 1.f)
- {
- return FALSE;
}
-
- /* prepare to test V parameter */
- LLVector3 qvec = tvec - edge1;
-
- /* calculate V parameter and test bounds */
- v = (dir * qvec) * inv_det;
-
- if (v < 0.f || u + v > 1.f)
- {
- return FALSE;
}
-
- /* calculate t, ray intersects triangle */
- t = (edge2 * qvec) * inv_det;
}
- if (intersection_a != NULL)
- *intersection_a = u;
- if (intersection_b != NULL)
- *intersection_b = v;
- if (intersection_t != NULL)
- *intersection_t = t;
-
-
- return TRUE;
+ return FALSE;
}
@@ -3487,99 +3405,47 @@ void LLVolume::generateSilhouetteVertices(std::vector<LLVector3> &vertices,
}
}
-S32 LLVolume::lineSegmentIntersect(const LLVector3& start, const LLVector3& end,
- S32 face,
- LLVector3* intersection,LLVector2* tex_coord, LLVector3* normal, LLVector3* bi_normal)
+S32 LLVolume::lineSegmentIntersect(const LLVector3& start, LLVector3& end) const
{
- S32 hit_face = -1;
-
- S32 start_face;
- S32 end_face;
+ S32 ret = -1;
- if (face == -1) // ALL_SIDES
- {
- start_face = 0;
- end_face = getNumFaces() - 1;
- }
- else
- {
- start_face = face;
- end_face = face;
- }
-
- LLVector3 dir = end - start;
-
- F32 closest_t = 2.f; // must be larger than 1
+ LLVector3 vec = end - start;
- for (S32 i = start_face; i <= end_face; i++)
+ for (S32 i = 0; i < getNumFaces(); i++)
{
- LLVolumeFace face = getVolumeFace((U32)i);
-
- LLVector3 box_center = (face.mExtents[0] + face.mExtents[1]) / 2.f;
- LLVector3 box_size = face.mExtents[1] - face.mExtents[0];
-
- if (LLLineSegmentBoxIntersect(start, end, box_center, box_size))
- {
- if (bi_normal != NULL) // if the caller wants binormals, we may need to generate them
- {
- genBinormals(i);
- }
-
- for (U32 tri = 0; tri < face.mIndices.size()/3; tri++)
- {
- S32 index1 = face.mIndices[tri*3+0];
- S32 index2 = face.mIndices[tri*3+1];
- S32 index3 = face.mIndices[tri*3+2];
+ const LLVolumeFace& face = getVolumeFace(i);
- F32 a, b, t;
-
- if (LLTriangleRayIntersect(face.mVertices[index1].mPosition,
- face.mVertices[index2].mPosition,
- face.mVertices[index3].mPosition,
- start, dir, &a, &b, &t, FALSE))
- {
- if ((t >= 0.f) && // if hit is after start
- (t <= 1.f) && // and before end
- (t < closest_t)) // and this hit is closer
+ for (U32 j = 0; j < face.mIndices.size()/3; j++)
{
- closest_t = t;
- hit_face = i;
+ //approximate normal
+ S32 v1 = face.mIndices[j*3+0];
+ S32 v2 = face.mIndices[j*3+1];
+ S32 v3 = face.mIndices[j*3+2];
- if (intersection != NULL)
- {
- *intersection = start + dir * closest_t;
- }
+ LLVector3 norm = (face.mVertices[v2].mPosition - face.mVertices[v1].mPosition) %
+ (face.mVertices[v3].mPosition - face.mVertices[v2].mPosition);
- if (tex_coord != NULL)
+ if (norm.magVecSquared() >= 0.00000001f)
{
- *tex_coord = ((1.f - a - b) * face.mVertices[index1].mTexCoord +
- a * face.mVertices[index2].mTexCoord +
- b * face.mVertices[index3].mTexCoord);
-
- }
-
- if (normal != NULL)
+ //get view vector
+ //LLVector3 view = (start-face.mVertices[v1].mPosition);
+ //if (view * norm < 0.0f)
{
- *normal = ((1.f - a - b) * face.mVertices[index1].mNormal +
- a * face.mVertices[index2].mNormal +
- b * face.mVertices[index3].mNormal);
- }
-
- if (bi_normal != NULL)
+ if (LLTriangleLineSegmentIntersect( face.mVertices[v1].mPosition,
+ face.mVertices[v2].mPosition,
+ face.mVertices[v3].mPosition,
+ end,
+ vec))
{
- *bi_normal = ((1.f - a - b) * face.mVertices[index1].mBinormal +
- a * face.mVertices[index2].mBinormal +
- b * face.mVertices[index3].mBinormal);
- }
-
+ vec = end-start;
+ ret = (S32) i;
}
}
}
}
}
-
- return hit_face;
+ return ret;
}
class LLVertexIndexPair
generated by cgit v1.2.3 (git 2.25.1) at 2025-02-08 17:32:31 +0000