bool isRaySphereIntersection(const MVector3 & origin, const MVector3 & direction, const MVector3 & sphereCenter, float sphereRadius, MVector3 * point)
{
MVector3 vec = origin - sphereCenter;
float b = direction.dotProduct(vec);
float c = vec.getSquaredLength() - (sphereRadius * sphereRadius);
float d = (b * b) - c;
if(d < 0)
return false;
float distance = -b - sqrtf(d);
point->x = (origin.x + (distance * direction.x));
point->y = (origin.y + (distance * direction.y));
point->z = (origin.z + (distance * direction.z));
return true;
}
bool getNearestRaytracedPosition(const MVector3 & origin, const MVector3 & dest, const void * indices, M_TYPES indicesType, const MVector3 * vertices, unsigned int size, MVector3 * intersection)
{
M_PROFILE_SCOPE(getNearestRaytracedPosition);
bool isRaytraced = false;
float dist;
float nearDist;
MVector3 I;
MVector3 rayVector = dest - origin;
// init near dist
nearDist = rayVector.getSquaredLength();
switch(indicesType)
{
case M_USHORT:
{
unsigned int v;
unsigned short * idx = (unsigned short *)indices;
for (v = 0; v < size; v += 3)
{
const MVector3 * v1 = &vertices[idx[v]];
const MVector3 * v2 = &vertices[idx[v+1]];
const MVector3 * v3 = &vertices[idx[v+2]];
// make normal
MVector3 normal = getTriangleNormal(*v1, *v2, *v3);
// compute ray intersection
if(isEdgeTriangleIntersection(origin, dest, *v1, *v2, *v3, normal, &I))
{
rayVector = I - origin;
dist = rayVector.getSquaredLength();
if(dist < nearDist)
{
nearDist = dist;
(*intersection) = I;
}
isRaytraced = true;
}
}
}
break;
case M_UINT:
{
unsigned int v;
unsigned int * idx = (unsigned int *)indices;
for (v = 0; v < size; v += 3)
{
const MVector3 * v1 = &vertices[idx[v]];
const MVector3 * v2 = &vertices[idx[v+1]];
const MVector3 * v3 = &vertices[idx[v+2]];
// make normal
MVector3 normal = getTriangleNormal(*v1, *v2, *v3);
// compute ray intersection
if(isEdgeTriangleIntersection(origin, dest, *v1, *v2, *v3, normal, &I))
{
rayVector = I - origin;
dist = rayVector.getSquaredLength();
if(dist < nearDist)
{
nearDist = dist;
(*intersection) = I;
}
isRaytraced = true;
}
}
}
break;
default:
break;
}
return isRaytraced;
}
