void Box::DoRender() const
{
glScalef(GetHalfSize().x, GetHalfSize().y, GetHalfSize().z);
glutSolidCube(2);
glPushAttrib(GL_LIGHTING_BIT);
glDisable(GL_LIGHTING);
glColor3f(1,1,1);
glutWireCube(2);
glPopAttrib();
}
void Box::meshify(int divide) {
// positive z is into the page
int id = 0;
Vector3 bound = GetHalfSize();
float x_base = -1 * bound[0];
float y_base = -1 * bound[1];
float z_base = -1 * bound[2];
Vertex * P111 = new Vertex(Vector3(x_base, bound[1], z_base), id); id = id + 1;
Vertex * P211 = new Vertex(Vector3(x_base, y_base, z_base), id); id = id + 1;
Vertex * P121 = new Vertex(Vector3(bound[0], bound[1], z_base), id); id = id + 1;
Vertex * P221 = new Vertex(Vector3(bound[0], y_base, z_base), id); id = id+1;
Vertex * P112 = new Vertex(Vector3(x_base, bound[1], bound[2]), id); id = id+1;
Vertex * P122 = new Vertex(Vector3(bound[0], bound[1], bound[2]), id); id = id + 1;
Vertex * P212 = new Vertex(Vector3(x_base, y_base, bound[2]), id); id = id + 1;
Vertex * P222 = new Vertex(Vector3(bound[0], y_base, bound[2]), id); id = id+1;
P111->addNeighbor(P112);
P111->addNeighbor(P211);
P111->addNeighbor(P121);
P211->addNeighbor(P111);
P211->addNeighbor(P212);
P211->addNeighbor(P221);
P121->addNeighbor(P111);
P121->addNeighbor(P221);
P121->addNeighbor(P122);
P221->addNeighbor(P211);
P221->addNeighbor(P222);
P221->addNeighbor(P121);
P112->addNeighbor(P122);
P112->addNeighbor(P212);
P112->addNeighbor(P111);
P122->addNeighbor(P112);
P122->addNeighbor(P222);
P122->addNeighbor(P121);
P222->addNeighbor(P122);
P222->addNeighbor(P221);
P222->addNeighbor(P212);
P212->addNeighbor(P222);
P212->addNeighbor(P112);
P212->addNeighbor(P211);
verticies.push_back(P111);
verticies.push_back(P121);
verticies.push_back(P221);
verticies.push_back(P211);
verticies.push_back(P112);
verticies.push_back(P122);
verticies.push_back(P222);
verticies.push_back(P212);
}
BOHGE_FORCEINLINE Aabbox3d operator* (const vector3<T>& scale ) const
{
vector3<T> center = GetCenter();
vector3<T> size = GetHalfSize();
size *= scale;
//注意旋转以后的顶点位置的前后有所变化，需要更改构造方式，此处会影响相交的判断
return Aabbox3d<T>( center - size , center + size );
}
Vector3 Box::GetNormalLocalInertialTensor() const
{
// TODO: is this correct? I am not sure what the 'Normal' Inertial Tensor is
// interial matrix for box is
// | (y^2 + z^2) 0 0 |
// I = (M/12) * | 0 (x^2 + z^2) 0 |
// | 0 0 (x^2 + y^2) |
Vector3 size = 2*GetHalfSize();
float x2 = size.x * size.x;
float y2 = size.y * size.y;
float z2 = size.z * size.z;
return (GetNormalMass()/12.0) * Vector3((y2+z2), (x2+z2), (x2+y2));
}
Ogre::Vector3 Box::GetClosestPoint(Vector3 const& p) const
{
// transform into local space
Vector3 op = GetTransformation().inverseAffine()*p;
Vector3 hs = GetHalfSize();
if(fabs(op.x) < hs.x && fabs(op.y) < hs.y && fabs(op.z) < hs.z)
{
// point inside box
return p;
}
Vector3 oc = Vector3(
std::min(std::max(op.x, -hs.x), hs.x),
std::min(std::max(op.y, -hs.y), hs.y),
std::min(std::max(op.z, -hs.z), hs.z));
return GetTransformation()*oc;
}
void Box::GetExtentsAlongAxis(Vector4 const& v, float & a, float & b) const
{
// The implementation of this function is optimized to the point of opacity.
// If you're interested in its inner workings, contact me directly.
// transform v into object space.
Vector4 ov = TransformPlane(v, GetTransformation().inverseAffine());
Vector3 ov3(ov.x, ov.y, ov.z);
// note: ov3 is unit length
// distance from center of box to plane
float dc = ov.w;
// distances along ov from center to each of the positive three faces, abs'ed and summed
float extDist = GetHalfSize().absDotProduct(ov3);
a = dc - extDist;
b = dc + extDist;
}
