void SweptAABB_BuildTriList(Vector3 start, Vector3 end, Vector3 extends, int nodeid, AABB_t AABBox, TriList_t triList)
{
// get the current node
Node_t node = m_pNodes[nodeid];
//
// fill in AABBox plane distances
//
AABBox.Dists[0] = -(node.m_BBox[0].X - ClipMap.EPSILON);
AABBox.Dists[1] = (node.m_BBox[1].X + ClipMap.EPSILON);
AABBox.Dists[2] = -(node.m_BBox[0].Y - ClipMap.EPSILON);
AABBox.Dists[3] = (node.m_BBox[1].Y + ClipMap.EPSILON);
AABBox.Dists[4] = -(node.m_BBox[0].Z - ClipMap.EPSILON);
AABBox.Dists[5] = (node.m_BBox[1].Z + ClipMap.EPSILON);
// test the swept box against the given node
if (SweptAABB_NodeTest(start, end, extends, AABBox))
{
//
// if leaf add tris to list
//
if ((node.m_fFlags & 0x01) > 0)
{
if (triList.Count < DISPCOLL_TRILIST_SIZE)
{
triList.ppTriList[triList.Count] = m_pTris[node.m_iTris[0]];
triList.ppTriList[triList.Count + 1] = m_pTris[node.m_iTris[1]];
triList.Count += 2;
}
return;
}
// continue testing with children nodes
else
{
SweptAABB_BuildTriList(start, end, extends, Nodes_GetChild(nodeid, 0), AABBox, triList);
SweptAABB_BuildTriList(start, end, extends, Nodes_GetChild(nodeid, 1), AABBox, triList);
SweptAABB_BuildTriList(start, end, extends, Nodes_GetChild(nodeid, 2), AABBox, triList);
SweptAABB_BuildTriList(start, end, extends, Nodes_GetChild(nodeid, 3), AABBox, triList);
}
}
}
void SweptAABB_IntersectTriList(Vector3 start, Vector3 end, Vector3 extends, float startf, float endf, ref trace_t trace, TriList_t trilist)
{
Vector3 impactNormal = new Vector3();
float impactDist = 0f;
Tri_t tri;
//
// intersect against all the flagged triangles in trilist
//
for (int iTri = 0; iTri < trilist.Count; iTri++)
{
// get the current displacement
tri = trilist.ppTriList[iTri];
// intersection test
IntersectAABoxSweptTriangle(start, end, extends,
m_pVerts[tri.m_uiVerts[0]],
m_pVerts[tri.m_uiVerts[2]],
m_pVerts[tri.m_uiVerts[1]],
tri.m_vecNormal, tri.m_flDist,
tri.m_nFlags, tri.m_iSurfProp,
/*fraction,*/ref trace, true);
}
}
public bool AABBSweep(Vector3 start, Vector3 end, Vector3 extends,
float startf, float endf, ref trace_t trace)
{
//
// create and initialize the triangle list
//
TriList_t trilist = new TriList_t();
//
// create and initialize the primary AABB
//
AABB_t AABBox = new AABB_t();
//
// sweep box against the axial-aligned bboxed quad-tree and generate an initial
// list of collision tris
//
SweptAABB_BuildTriList(start, end, extends, 0, AABBox, trilist);
// save the starting fraction
float preIntersectionFrac = trace.fraction;
//
// sweep axis-aligned bounding box against the triangles in the list
//
if (trilist.Count > 0)
{
SweptAABB_IntersectTriList(start, end, extends, startf, endf, ref trace, trilist);
}
// collision
if (preIntersectionFrac > trace.fraction)
return true;
// no collision
return false;
}