// =====================================================================================
// SnapToPlane
// =====================================================================================
void SnapToPlane(const dplane_t* const plane, vec_t* const point, vec_t offset)
{
#ifdef HLRAD_MATH_VL
vec_t dist;
dist = DotProduct (point, plane->normal) - plane->dist;
dist -= offset;
VectorMA (point, -dist, plane->normal, point);
#else
vec3_t delta;
vec3_t proj;
vec3_t pop; // point on plane
VectorScale(plane->normal, plane->dist + offset, pop);
VectorSubtract(point, pop, delta);
ProjectionPoint(delta, plane->normal, proj);
VectorSubtract(delta, proj, delta);
VectorAdd(delta, pop, point);
#endif
}
// Will modify the plane with the new dist
void TranslatePlane(dplane_t* plane, const vec_t* delta)
{
#ifdef HLRAD_FASTMATH
plane->dist += DotProduct(plane->normal,delta);
#else
vec3_t proj;
vec_t magnitude;
ProjectionPoint(delta, plane->normal, proj);
magnitude = VectorLength(proj);
if (DotProduct(plane->normal, delta) > 0) //if zero, magnitude will be zero.
{
plane->dist += magnitude;
}
else
{
plane->dist -= magnitude;
}
#endif
}
