// Right now there are some inconsistencies in the way this function behaves
// compared to the OBB-OBB version. I think this one is correct, but it's tough to tell...
std::list<Contact> OBB::GetClosestPoints(const AABB& other) const {
std::list<Contact> ret;
// Find the vector from our center to theirs
vec2 centerVecN = other.C - C;
vec2 faceN(0);
// Make it a unit vector in the direction of largest magnitude
faceN = glm::normalize(maxComp(centerVecN));
// Get supporting vertex / vertices along that direction
std::array<int, 2> sV;
int nSupportVerts = GetSupportIndices(faceN, sV);
// one support vert means a vertex-face collision
if (nSupportVerts == 1) {
// Two contact points; the support vertex, and it's best neighbor
std::array<glm::vec2, 2> pA_arr = GetSupportNeighbor(faceN, sV[0]);
for (auto& pA : pA_arr) {
vec2 pB = other.clamp(pA);
float d = glm::distance(pA, pB);
ret.emplace_back((RigidBody_2D *)this, (RigidBody_2D *)&other, pA, pB, faceN, d);
}
}
// face-face collsion, average two support verts into one contact point
else {
vec2 pA = 0.5f * (GetVert(sV[0]) + GetVert(sV[1]));
vec2 pB = other.clamp(pA);
float d = glm::distance(pA, pB);
ret.emplace_back((RigidBody_2D *)this, (RigidBody_2D *)&other, pA, pB, faceN, d);
}
return ret;
}
// Indices of the vertices returned by the above function
int OBB::GetSupportIndices(vec2 n, std::array<int, 2>& sV) const {
// Find the furthest vertex
float dMin = -FLT_MAX;
for (int i = 0; i < 4; i++) {
vec2 v = GetVert(i);
float d = glm::dot(n, v);
if (d > dMin) {
dMin = d;
sV[0] = i;
}
}
int num(1);
// If there's a different vertex
for (int i = 0; i < 4; i++) {
if (i == sV[0])
continue;
vec2 v = GetVert(i);
float d = glm::dot(n, v);
// That's pretty close...
if (feq(d, dMin, 100.f * kEPS)) {
// Take it too
dMin = d;
sV[num++] = i;
}
}
return num;
}
//-----------------------------------------------------------------------------
//-----------------------------------------------------------------------------
void CVRADDispColl::DispUVToSurfDiagonalTLtoBR( int snapU, int snapV, int nextU, int nextV,
float fracU, float fracV, Vector &surfPt,
float pushEps )
{
// get displacement width
int width = GetWidth();
if( ( fracU + fracV ) >= ( 1.0f + TRIEDGE_EPSILON ) )
{
int triIndices[3];
triIndices[0] = nextV * width + snapU;
triIndices[1] = nextV * width + nextU;
triIndices[2] = snapV * width + nextU;
Vector triVerts[3];
for( int i = 0; i < 3; i++ )
{
GetVert( triIndices[i], triVerts[i] );
}
Vector edgeU, edgeV;
edgeU = triVerts[0] - triVerts[1];
edgeV = triVerts[2] - triVerts[1];
surfPt = triVerts[1] + edgeU * ( 1.0f - fracU ) + edgeV * ( 1.0f - fracV );
// get face normal and push point away from surface the given pushEps
Vector vNormal;
vNormal = CrossProduct( edgeU, edgeV );
VectorNormalize( vNormal );
surfPt += ( vNormal * pushEps );
}
else
{
int triIndices[3];
triIndices[0] = snapV * width + snapU;
triIndices[1] = nextV * width + snapU;
triIndices[2] = snapV * width + nextU;
Vector triVerts[3];
for( int i = 0; i < 3; i++ )
{
GetVert( triIndices[i], triVerts[i] );
}
Vector edgeU, edgeV;
edgeU = triVerts[2] - triVerts[0];
edgeV = triVerts[1] - triVerts[0];
// get the position
surfPt = triVerts[0] + edgeU * fracU + edgeV * fracV;
// get face normal and push point away from surface the given pushEps
Vector vNormal;
vNormal = CrossProduct( edgeU, edgeV );
VectorNormalize( vNormal );
surfPt += ( vNormal * pushEps );
}
}
//-----------------------------------------------------------------------------
//-----------------------------------------------------------------------------
void CVRADDispColl::ClosestBaseFaceData( Vector const &worldPt, Vector &closePt,
Vector &closeNormal )
{
Vector delta;
float minDist = 99999.0f;
int ndxMin = -1;
for( int ndxPt = 0; ndxPt < 4; ndxPt++ )
{
delta = worldPt - m_Points[ndxPt];
float dist = delta.Length();
if( dist < minDist )
{
minDist = dist;
ndxMin = ndxPt;
}
}
int width = GetWidth();
int height = GetHeight();
switch( ndxMin )
{
case 0: { ndxMin = 0; break; }
case 1: { ndxMin = ( height - 1 ) * width; break; }
case 2: { ndxMin = ( height * width ) - 1; break; }
case 3: { ndxMin = width - 1; break; }
default: { return; }
}
GetVert( ndxMin, closePt );
GetVertNormal( ndxMin, closeNormal );
}
void CSubTriangle::GetDivision(int& o_nStartOfLongest, CVector3DF& o_vMidPoint, CVector3DF& o_vMidPointBar) const
{
//get parent bezier patch
// const CBezierPatch& ParentBezierPatch = m_pParent_SubTriangle ? m_pParent_SubTriangle->GetBezierPatch() : m_Parent.GetBezierPatch();
float fDistance = 0.0f;
CVector3DF vMidPointBar, vMidPoint;
for (int i = 0; i < 3; i++)
{
const int j = (i + 1) % 3;
vMidPointBar = (GetVertBar(i) + GetVertBar(j)) / 2.0f;
vMidPoint = m_Parent.GetBezierPatch().GetPointFromBarycentric(vMidPointBar);
const float fNewDistance = (GetVert(i) - vMidPoint).Length();// this should work with bezier stuff
if (fNewDistance > fDistance)
{
fDistance = fNewDistance;
o_nStartOfLongest = i;
o_vMidPoint = vMidPoint;
o_vMidPointBar = vMidPointBar;
}
}
}
// Pick the best support neighbor along n
// It's critical that this function return an array where the vertices
// are in the proper clockwise order
std::array<vec2, 2> OBB::GetSupportNeighbor(vec2 n, int idx) const {
std::array<vec2, 2> ret;
vec2 vb = GetVert(idx);
vec2 va = GetVert(idx - 1);
vec2 vc = GetVert(idx + 1);
vec2 nab = glm::normalize(perp(vb - va));
vec2 nbc = glm::normalize(perp(vc - vb));
float d1 = glm::dot(nab, n);
float d2 = glm::dot(nbc, n);
if (d1 > d2)
return{ { va, vb } };
return{ { vb, vc } };
}
// Not tested, and there may be a better way...
bool IsOverlapping( Circle * pCirc, OBB * pOBB )
{
for ( int i = 0; i < 4; i++ )
if ( IsPointInside( GetVert( pOBB, i ), pCirc ) )
return true;
return IsPointInside( pCirc->v2Center, pOBB );
}
//-----------------------------------------------------------------------------
void CCollision::Resolve()
{
CIwManaged::Resolve();
IwResolveManagedHash(&m_pModel, IW_GRAPHICS_RESTYPE_MODEL);
//Build face normals (done on resolve to save disk space)
for(uint32 i = 0; i < m_Points.size(); i+=3)
{
CIwVec3 v1 = (CIwVec3)GetVert(i);
CIwVec3 v2 = (CIwVec3)GetVert(i+1);
CIwVec3 v3 = (CIwVec3)GetVert(i+2);
CIwSVec3 cross = (CIwSVec3)(v2 - v1).Cross(v3 - v1);
if( cross != CIwSVec3::g_Zero )
cross.Normalise();
m_Norms.push_back(cross);
}
}
void OpenGLRect::DrawMyBothRect(const float& fLineWidth /*= 1.0f*/)
{
GetVert(m_fRectVert);
GetColor(m_fRectColor);
DrawMyRect(1.0f, GL_QUADS);
GetBorderVert(m_fRectVert);
GetBorderColor(m_fRectColor);
DrawMyRect(fLineWidth);
}
// Resolve ghost modelspace location
void GhostCollision::ResolveLocation() {
float y1 = INT32_MAX;
float y2 = INT32_MIN;
float x1 = INT32_MAX;
float x2 = INT32_MIN;
for (uint32 i = 0; i < m_Points.size(); i++)
{
CIwFVec3 v = (CIwFVec3)GetVert(i);
if (v.y < y1) y1 = v.y;
if (v.y > y2) y2 = v.y;
if (v.x < x1) x1 = v.x;
if (v.x > x2) x2 = v.x;
}
ghostY = y2;
ghostX = x1;
ghostW = x2 - x1;
}
bool CSubTriangle::Intersect(const CRay &ray, CIntersactionInfo &intersectionInfo, bool bDebug) const
{
// intersectionInfo.m_nBezierIntersections += 1;
// QElapsedTimer timer;
// timer.start();
bool bIntersect = false;
if (intersectionInfo.m_bHighQuality)
{
bIntersect = m_Parent.GetBezierPatch().IntersectHighQuality(ray, intersectionInfo, *this, bDebug);
// if (b && GetSettings()->m_bNormalSmoothing)
// {
// intersectionInfo.m_vNormal = GetSubSurfSmoothedNormal(intersectionInfo.m_vBarCoordsGlobal);
// }
}
else
{
bIntersect = CUtils::IntersectTriangle(ray, intersectionInfo, GetVert(0), GetVert(1), GetVert(2), m_vABar, m_vBBar, m_vCBar);
if (bIntersect)
{
if (GetSettings()->m_bNormalSmoothing)
{
//Smoothed normal
CVector3DF vNormalA = intersectionInfo.m_vBarCoordsGlobal.X() * m_Parent.A().Normal_Get();
CVector3DF vNormalB = intersectionInfo.m_vBarCoordsGlobal.Y() * m_Parent.B().Normal_Get();
CVector3DF vNormalC = intersectionInfo.m_vBarCoordsGlobal.Z() * m_Parent.C().Normal_Get();
intersectionInfo.m_vNormal = vNormalA + vNormalB + vNormalC;
intersectionInfo.m_vNormal.Normalize();
}
else
{
CVector3DF m_vAB = GetVert(1)- GetVert(0);
CVector3DF m_vAC = GetVert(2)- GetVert(0);
intersectionInfo.m_vNormal = CVector3DF::Normal(m_vAB, m_vAC);
}
}
}
// intersectionInfo.m_nObjTime += timer.nsecsElapsed();
return bIntersect;
}
void OpenGLRect::DrawMyFillRect(void)
{
GetVert(m_fRectVert);
GetColor(m_fRectColor);
DrawMyRect(1.0f, GL_QUADS);
}
// Simlar to the AABB case, but we only care about the center of the circle
std::list<Contact> GetSpecContacts( Circle * pCirc, AABB * pAABB)
{
// Determine which feature region we're on
vec2 n;
int vIdx( -1 );
// top/bottom face region
if ( (pAABB->Right() < pCirc->v2Center.x || pAABB->Left() > pCirc->v2Center.x) == false )
{
// Circle is below box
if ( pCirc->v2Center.y < pAABB->Bottom() )
{
vIdx = 1;
n = vec2( 0, 1 );
}
else
{
vIdx = 3;
n = vec2( 0, -1 );
}
}
// left/right face region
else if ( (pAABB->Top() < pCirc->v2Center.y || pAABB->Bottom() > pCirc->v2Center.y) == false )
{
// Circle is to the left of the box
if ( pCirc->v2Center.x < pAABB->Left() )
{
vIdx = 2;
n = vec2( 1, 0 );
}
else
{
vIdx = 0;
n = vec2( -1, 0 );
}
}
// Vertex region
else
{
// Determine which vertex
bool bAIsLeft = (pCirc->v2Center.x < pAABB->Left());
bool bAIsBelow = (pCirc->v2Center.y < pAABB->Bottom());
if ( bAIsLeft )
{
if ( bAIsBelow )
vIdx = 2;
else
vIdx = 3;
}
else
{
if ( bAIsBelow )
vIdx = 1;
else
vIdx = 0;
}
// We don't need to average contact positions for the corner case
vec2 posB = GetVert( pAABB, vIdx );
n = glm::normalize( posB - pCirc->v2Center );
vec2 posA = pCirc->v2Center + pCirc->circData.fRadius * n;
float fDist = glm::distance( posA, posB );
return{ Contact( pCirc, pAABB, posA, posB, n, fDist ) };
}
// For a face region collision, we want to make sure the contact knows it's
// working with one of the box's face normals (meaning distance is along that normal)
vec2 posB = 0.5f*(GetVert( pAABB, vIdx ) + GetVert( pAABB, vIdx + 1 ));
//n = glm::normalize( posB - pCirc->v2Center );
vec2 posA = pCirc->v2Center + pCirc->circData.fRadius * n;
float fDist = glm::dot( posB - posA, n );
return{ Contact( pCirc, pAABB, posA, posB, n, fDist ) };
}
//-----------------------------------------------------------------------------
int32 GhostCollision::GetFaceUnderCursor(int32 x, int32 y)
{
//Calculate pos/dir of cursor from camera
CIwFVec3 pos = IwGxGetViewMatrix().t;
CIwFVec3 dir(x, y, IwGxGetPerspMul());
dir.x -= IwGxGetScreenWidth()/2;
dir.y -= IwGxGetScreenHeight()/2;
//Extend to the far plane
dir *= IW_FIXED_DIV(IwGxGetFarZ(), IwGxGetPerspMul());
//Transform pos/dir into model space
dir = IwGxGetViewMatrix().RotateVec(dir);
dir = modelMatrix->TransposeRotateVec(dir);
//Use more accurate normalise
dir.Normalise();
// Scale to touch far plane
dir *= IwGxGetFarZ();
pos = modelMatrix->TransposeTransformVec(pos);
//find first face intersection
int32 minf = INT32_MAX; //nearest intersection distance
uint32 nearest = 0; //nearest intersection index
for (uint32 i = 0; i < m_Points.size(); i += 3)
{
CIwFVec3 v1 = (CIwFVec3)GetVert(i);
CIwFVec3 v2 = (CIwFVec3)GetVert(i+1);
CIwFVec3 v3 = (CIwFVec3)GetVert(i+2);
float f = 0;
if (IwIntersectLineTriNorm(pos, dir, v1, v2, v3, m_Norms[i/3], f)) {
if (f < minf)
{
minf = f;
nearest = i;
}
}
/*{ // Draw the custom resource. Kills fps but helps debugging.
CIwMaterial* pMat = IW_GX_ALLOC_MATERIAL();
pMat->SetColAmbient(0xff0000ff);
pMat->SetCullMode(CIwMaterial::CULL_NONE);
IwGxSetMaterial(pMat);
CIwFVec3* verts = IW_GX_ALLOC(CIwFVec3, 3);
verts[0] = v1;
verts[1] = v2;
verts[2] = v3;
IwGxSetVertStreamModelSpace(verts, 3);
IwGxDrawPrims(IW_GX_TRI_LIST, NULL, 3);
}*/
}
if (minf != INT32_MAX)
{
return nearest;
}
return -1;
}
