bool cBoundingBox::CalcLineIntersection(const Vector3d & a_Min, const Vector3d & a_Max, const Vector3d & a_Line1, const Vector3d & a_Line2, double & a_LineCoeff, eBlockFace & a_Face) { if (IsInside(a_Min, a_Max, a_Line1)) { // The starting point is inside the bounding box. a_LineCoeff = 0; a_Face = BLOCK_FACE_NONE; // No faces hit return true; } eBlockFace Face = BLOCK_FACE_NONE; double Coeff = Vector3d::NO_INTERSECTION; // Check each individual bbox face for intersection with the line, remember the one with the lowest coeff double c = a_Line1.LineCoeffToXYPlane(a_Line2, a_Min.z); if ((c >= 0) && (c < Coeff) && IsInside(a_Min, a_Max, a_Line1 + (a_Line2 - a_Line1) * c)) { Face = (a_Line1.z > a_Line2.z) ? BLOCK_FACE_ZP : BLOCK_FACE_ZM; Coeff = c; } c = a_Line1.LineCoeffToXYPlane(a_Line2, a_Max.z); if ((c >= 0) && (c < Coeff) && IsInside(a_Min, a_Max, a_Line1 + (a_Line2 - a_Line1) * c)) { Face = (a_Line1.z > a_Line2.z) ? BLOCK_FACE_ZP : BLOCK_FACE_ZM; Coeff = c; } c = a_Line1.LineCoeffToXZPlane(a_Line2, a_Min.y); if ((c >= 0) && (c < Coeff) && IsInside(a_Min, a_Max, a_Line1 + (a_Line2 - a_Line1) * c)) { Face = (a_Line1.y > a_Line2.y) ? BLOCK_FACE_YP : BLOCK_FACE_YM; Coeff = c; } c = a_Line1.LineCoeffToXZPlane(a_Line2, a_Max.y); if ((c >= 0) && (c < Coeff) && IsInside(a_Min, a_Max, a_Line1 + (a_Line2 - a_Line1) * c)) { Face = (a_Line1.y > a_Line2.y) ? BLOCK_FACE_YP : BLOCK_FACE_YM; Coeff = c; } c = a_Line1.LineCoeffToYZPlane(a_Line2, a_Min.x); if ((c >= 0) && (c < Coeff) && IsInside(a_Min, a_Max, a_Line1 + (a_Line2 - a_Line1) * c)) { Face = (a_Line1.x > a_Line2.x) ? BLOCK_FACE_XP : BLOCK_FACE_XM; Coeff = c; } c = a_Line1.LineCoeffToYZPlane(a_Line2, a_Max.x); if ((c >= 0) && (c < Coeff) && IsInside(a_Min, a_Max, a_Line1 + (a_Line2 - a_Line1) * c)) { Face = (a_Line1.x > a_Line2.x) ? BLOCK_FACE_XP : BLOCK_FACE_XM; Coeff = c; } if (Coeff >= Vector3d::NO_INTERSECTION) { // There has been no intersection return false; } a_LineCoeff = Coeff; a_Face = Face; return true; }