/**
* @param[in] tile Tile to check (normally 0 - except in assembled maps)
* @param[in] start trace start vector
* @param[in] end trace end vector
* @param[in] mins box mins
* @param[in] maxs box maxs
* @param[in] headnode if < 0 we are in a leaf node
* @param[in] contentmask content flags the trace should stop at (see MASK_*)
* @param[in] brushrejects brushes the trace should ignore (see MASK_*)
* @param[in] origin center for rotating objects
* @param[in] angles current rotation status (in degrees) for rotating objects
* @param[in] rmaShift how much the object was shifted by the RMA process (needed for doors)
* @param[in] fraction The furthest distance needed to trace before we stop.
* @brief Handles offseting and rotation of the end points for moving and rotating entities
* @sa CM_BoxTrace
*/
trace_t CM_HintedTransformedBoxTrace (mapTile_t *tile, const vec3_t start, const vec3_t end, const vec3_t mins, const vec3_t maxs, const int headnode, const int contentmask, const int brushrejects, const vec3_t origin, const vec3_t angles, const vec3_t rmaShift, const float fraction)
{
trace_t trace;
vec3_t start_l, end_l;
vec3_t forward, right, up;
vec3_t temp;
bool rotated;
/* subtract origin offset */
VectorSubtract(start, origin, start_l);
VectorSubtract(end, origin, end_l);
/* rotate start and end into the models frame of reference */
if (headnode != tile->box_headnode && VectorNotEmpty(angles)) {
rotated = true;
} else {
rotated = false;
}
if (rotated) {
AngleVectors(angles, forward, right, up);
VectorCopy(start_l, temp);
start_l[0] = DotProduct(temp, forward);
start_l[1] = -DotProduct(temp, right);
start_l[2] = DotProduct(temp, up);
VectorCopy(end_l, temp);
end_l[0] = DotProduct(temp, forward);
end_l[1] = -DotProduct(temp, right);
end_l[2] = DotProduct(temp, up);
}
/* When tracing through a model, we want to use the nodes, planes etc. as calculated by ufo2map.
* But nodes and planes have been shifted in case of an RMA. At least for doors we need to undo the shift. */
if (VectorNotEmpty(origin)) { /* only doors seem to have their origin set */
VectorAdd(start_l, rmaShift, start_l); /* undo the shift */
VectorAdd(end_l, rmaShift, end_l);
}
/* sweep the box through the model */
trace = TR_BoxTrace(tile, start_l, end_l, mins, maxs, headnode, contentmask, brushrejects, fraction);
trace.mapTile = tile->idx;
if (rotated && trace.fraction != 1.0) {
vec3_t a;
/** @todo figure out how to do this with existing angles */
VectorNegate(angles, a);
AngleVectors(a, forward, right, up);
VectorCopy(trace.plane.normal, temp);
trace.plane.normal[0] = DotProduct(temp, forward);
trace.plane.normal[1] = -DotProduct(temp, right);
trace.plane.normal[2] = DotProduct(temp, up);
}
VectorInterpolation(start, end, trace.fraction, trace.endpos);
return trace;
}
/**
* @brief Rotates AABB around given origin point; note that it will expand the box unless all angles are multiples of 90 degrees
* @note Not fully verified so far
*/
void AABB::rotateAround (const vec3_t origin, const vec3_t angles) {
/* reject non-rotations */
if (VectorEmpty(angles))
return;
/* construct box-centered coordinates (center and corners) */
vec3_t center, halfDiagonal;
VectorInterpolation(mins, maxs, 0.5f, center);
VectorSubtract(maxs, center, halfDiagonal);
/* offset coordinate frame to rotation origin */
VectorSubtract(center, origin, center);
/* rotate center by given angles */
vec3_t m[3];
VectorCreateRotationMatrix(angles, m);
vec3_t newCenter;
VectorRotate(m, center, newCenter);
/* short-circuit calculation of the rotated box half-extents */
/* shortcut is: instead of calculating all 8 AABB corners, use the symmetry by rotating box around it's center. */
VectorAbs(m[0]);
VectorAbs(m[1]);
VectorAbs(m[2]);
vec3_t newHalfDiagonal;
VectorRotate(m, halfDiagonal, newHalfDiagonal);
/* de-offset coordinate frame from rotation origin */
VectorAdd(newCenter, origin, newCenter);
/* finally, combine results into new AABB */
VectorAdd(newCenter, newHalfDiagonal, maxs);
VectorSubtract(newCenter, newHalfDiagonal, mins);
}
