int segIntersect(Point2 A, Point2 B, Point2 C, Point2 D, Point2 &InterPt)
{
Vector2 b, d, dp, bp, c;
b.set((B.x-A.x) , (B.y-A.y));
d.set((D.x-C.x) , (D.y-C.y));
bp.set(b.y , -b.x);
dp.set(d.y , -d.x);
c.set((C.x-A.x) , (C.y-A.y));
float t, u, dp_b;
dp_b=dp.x*b.x + dp.y*b.y;
if(dp_b != 0)
{
t=(dp.x*c.x + dp.y*c.y)/dp_b ;
u=-(bp.x*c.x + bp.y*c.y)/(bp.x*d.x + bp.y*d.y);
if((t>0 && t<1) && (u>0 && u<1))
{
InterPt.set((A.x+b.x*t) , (A.y+b.y*t));
return 0; }
else
return 1;
}
else
{
if((c.x*b.y - c.y*b.x)!=0)
return -1;
}
}
float dotProduct(Point2 A, Point2 B)
{
Point2 ret;
ret.set((A.getX()*B.getX()),(A.getY()*B.getY()));
int r = ret.getX() + ret.getY();
return r;
}
Point2 addPoints(Point2 A, Point2 B)
{
int x = B.getX() + A.getX();
int y = B.getY() + A.getY();
Point2 ret;
ret.set(x,y);
return ret;
}
Point2 subtactPoints(Point2 A, Point2 B)
{
int x = B.getX() - A.getX();
int y = B.getY() - A.getY();
Point2 ret;
ret.set(x,y);
return ret;
}
void lineTo(Point2 p)
{
glBegin(GL_LINES);
glVertex2f(CP.x, CP.y);
glVertex2f(p.x, p.y);
glEnd();
glFlush();
CP.set(p);
}
Point2 interact(Point2 A, Point2 B, Point2 C, Point2 D)
{
Point2 inter;
float a,b,c,d,k1,k2,x,y;
a=A.y-B.y;
b=B.x-A.x;
c=C.y-D.y;
d=D.x-C.x;
k1=a*A.x + b*A.y;
k2=c*C.x + d*C.y;
x=(d*k1 - b*k2)/(a*d - b*c);
//y=(c*k1 - a*k2)/(b*c -a*d);
y=( a*k2 -c*k1 )/(a*d - b*c );
inter.set(x , y);
return inter;
}
Point2 scalePoint(float A, Point2 B)
{
Point2 ret;
ret.set(A*B.getX(), A*B.getY());
return ret;
}
Point2 getNormal(Point2 A)
{
Point2 ret;
ret.set(-A.getY(), A.getX());
return ret;
}
void moveTo(Point2 p)
{
CP.set(p);
}
//function that detects mouse clicks and creates the polygon
void myMouseState(int button, int state, int x, int y)
{
if (initializeComplete == false)
{
if ((button == GLUT_LEFT_BUTTON) && (state == GLUT_DOWN))
{
polyPoint[numPoints].set((float) x, (float) (WINDOW_HEIGHT-y));
++numPoints;
}
else if ((button == GLUT_RIGHT_BUTTON) && (state == GLUT_DOWN))
initializeComplete = true;
glutPostRedisplay();
}
else
{
switch (button)
{
case (GLUT_RIGHT_BUTTON):
if (state == GLUT_DOWN)
{
moveEnabled = false;
for (int index=0; index<numPoints; index++)
{
if ((x < ((int)polyPoint[index].getX() + 20)) &&
(x > ((int)polyPoint[index].getX() - 20)) &&
(y < (WINDOW_HEIGHT - (int)polyPoint[index].getY() + 20)) &&
(y > (WINDOW_HEIGHT - (int)polyPoint[index].getY() - 20)))
{
moveEnabled = true;
polyIndex = index;
}
}
}
else if (state == GLUT_UP)
{
moveEnabled = false;
if (firstPointDrawn == true)
{
//pointInside = true; //remove this--for test only
Point2 *polyPointPtr;
polyPointPtr = &polyPoint[0];
insideOutside(testPoint, polyPointPtr, numPoints);
}
}
break;
case (GLUT_LEFT_BUTTON):
if (state == GLUT_DOWN)
{
//pointInside = false; //remove this--for test only
Point2 *polyPointPtr;
polyPointPtr = &polyPoint[0];
testPoint.set((float) x, (float) (WINDOW_HEIGHT-y));
firstPointDrawn = true;
insideOutside(testPoint, polyPointPtr, numPoints);
}
break;
default:
break;
}
}
void GetRelationTable(MPMesh* pMesh, MPMesh::FaceHandle curFace, MPMesh::FaceHandle seedFace,
Relation* relationSeed, unsigned nMesh, Octree<>* pOctree, Relation*& output)
{
// 讨论相邻的两个三角形，如何从一个三角形导出另一个三角形的关系表的问题
output = new Relation[nMesh];
memcpy(output, relationSeed, sizeof(Relation)*nMesh);
if (seedFace == curFace) return;
ISectTriangle* triSeed = pMesh->property(pMesh->SurfacePropHandle, seedFace);
ISectTriangle* triCur = pMesh->property(pMesh->SurfacePropHandle, curFace);
if (!triSeed || (!triSeed->coplanarTris.size() && !triSeed->segs.size()))
{
assert(triCur);
MarkNARelation(triCur, output);
}
else
{
int index = TestNeighborIndex(pMesh, seedFace, curFace);
assert(index != -1);
Vec3d* v[3];
unsigned nv = triSeed->vertices.size();
GetCorners(pMesh, seedFace, v[0], v[1], v[2]);
int a = triSeed->xi;
int b = triSeed->yi;
#ifdef _DEBUG
Vec3d* u[3];
GetCorners(pMesh, curFace, u[0], u[1], u[2]);
#endif
Point2 p[3];
p[0].set((*v[0])[a], (*v[0])[b]);
p[1].set((*v[1])[a], (*v[1])[b]);
p[2].set((*v[2])[a], (*v[2])[b]);
a = (index+1)%3;
b = (index+2)%3;
Point2 testPoint;
testPoint.set(p[a].x()+p[b].x()-p[index].x(), p[a].y()+p[b].y()-p[index].y());
// 首先用BSP把所有的关系都弄出来
for (auto& pair: triSeed->segs)
output[pair.first] = BSP2DInOutTest(pair.second.bsp, &testPoint);
// 如果存在共面，那么BSP的测量是不准确的，所以置0
for (auto& pair2: triSeed->coplanarTris)
{
if (output[pair2.first] == REL_NOT_AVAILABLE)
output[pair2.first] = REL_UNKNOWN;
}
// 对所有的相交元置-1
if (triCur) MarkNARelation(triCur, output);
std::vector<unsigned> errorList;
// 这个时候，按道理来说，所有的关系已经确定
// 但因为存在误差，可能存在为0的关系
for (auto& pair2: triSeed->coplanarTris)
{
if (output[pair2.first] == REL_UNKNOWN)
errorList.push_back(pair2.first);
}
if (errorList.size())
{
Vec3d *g[3];
GetCorners(pMesh, curFace, g[0], g[1], g[2]);
auto bc = (*g[0]+*g[1]+*g[2])/3.0;
for (auto index: errorList)
output[index] = PolyhedralInclusionTest(bc, pOctree, index, pOctree->pMesh[index]->bInverse);
}
}
}
