/******************************************************************************
* Determine color contribution of a lightsource (Phong model)
* Specular part is returned in seperate parameter and added later
*****************************************************************************/
const ntlColor
ntlLightObject::getShadedColor(const ntlRay &reflectedRay, const ntlVec3Gfx lightDir,
ntlMaterial *surf, ntlColor &highlight) const
{
gfxReal ldot = dot(lightDir, reflectedRay.getNormal()); /* equals cos( angle(L,N) ) */
ntlColor reflected_color = ntlColor(0.0); /* adds up to total reflected color */
if(mpGlob->getDebugOut() > 5) errorOut("Lighting dir:"<<lightDir<<" norm:"<<reflectedRay.getNormal()<<" "<<ldot );
/* lambertian reflection model */
if (ldot > 0.0) {
//ldot *= -1.0;
reflected_color += surf->getDiffuseRefl() * (getColor() * ldot );
/* specular part */
/* specular reflection only makes sense, when the light is facing the surface,
as the highlight is supposed to be a reflection of the lightsource, it cannot
be reflected on surfaces with ldot<=0, as this means the arc between light
and normal is more than 90 degrees. If this isn't done, ugly moiree patterns appear
in the highlights, and refractions have strange patterns due to highlights on the
inside of the surface */
gfxReal spec = dot(reflectedRay.getDirection(), lightDir); // equals cos( angle(R,L) )
if((spec > 0.0) && (surf->getSpecular()>0)) {
spec = pow( spec, surf->getSpecExponent() ); /* phong exponent */
highlight += getColor() * surf->getSpecular() * spec;
//errorOut( " "<< surf->getName() <<" S "<<highlight<<" "<<spec<<" "<<surf->getSpecular()<<" "<<surf->getSpecExponent() );
}
}
return ntlColor(reflected_color);
}
/******************************************************************************
* Illuminate the given point on an object
*****************************************************************************/
ntlColor ntlLightObject::illuminatePoint(ntlRay &reflectedRay, ntlGeometryObject *closest,
ntlColor &highlight )
{
/* is this light active? */
if(!mActive) { return ntlColor(0.0); }
gfxReal visibility = 1.0; // how much of light is visible
ntlVec3Gfx intersectionPos = reflectedRay.getOrigin();
ntlColor current_color = ntlColor(0.0);
ntlMaterial *clossurf = closest->getMaterial();
ntlVec3Gfx lightDir = (mvPosition - intersectionPos);
gfxReal lightDirNorm = normalize(lightDir);
// where is the lightsource ?
ntlRay rayOfLight(intersectionPos, lightDir, 0, 1.0, mpGlob );
if( (1) && (mCastShadows)&&(closest->getReceiveShadows()) ) {
ntlTriangle *tri;
ntlVec3Gfx triNormal;
gfxReal trit;
mpGlob->getRenderScene()->intersectScene(rayOfLight, trit, triNormal, tri, TRI_CASTSHADOWS);
if(( trit>0 )&&( trit<lightDirNorm )) visibility = 0.0;
if(mpGlob->getDebugOut() > 5) errorOut("Omni lighting with "<<visibility );
}
/* is light partly visible ? */
//? visibility=1.;
if (visibility>0.0) {
ntlColor highTemp(0.0); // temporary highlight color to multiply highTemp with offFac
current_color = getShadedColor(reflectedRay, lightDir, clossurf, highTemp) * visibility;
highlight += highTemp * visibility;
if(mpGlob->getDebugOut() > 5) errorOut("Omni lighting color "<<current_color );
}
return current_color;
}
/******************************************************************************
* distance to plane function for nodes
*****************************************************************************/
gfxReal ntlTree::distanceToPlane(BSPNode *curr, ntlVec3Gfx plane, ntlRay ray) const
{
return ( (plane[curr->axis]-ray.getOrigin()[curr->axis]) / ray.getDirection()[curr->axis] );
}
void ntlTree::intersectX(const ntlRay &ray, gfxReal &distance,
ntlVec3Gfx &normal,
ntlTriangle *&tri,
int flags, bool forceNonsmooth) const
{
gfxReal mint = GFX_REAL_MAX; /* current minimal t */
ntlVec3Gfx retnormal; /* intersection (interpolated) normal */
gfxReal mintu=0.0, mintv=0.0; /* u,v for min t intersection */
BSPNode *curr, *nearChild, *farChild; /* current node and children */
gfxReal planedist, mindist, maxdist;
ntlVec3Gfx pos;
ntlTriangle *hit = NULL;
tri = NULL;
ray.intersectCompleteAABB(mStart,mEnd,mindist,maxdist); // +X
if((maxdist < 0.0) ||
(!mpRoot) ||
(mindist == GFX_REAL_MAX) ||
(maxdist == GFX_REAL_MAX) ) {
distance = -1.0;
return;
}
mindist -= getVecEpsilon();
maxdist += getVecEpsilon();
/* stack init */
mpNodeStack->elem[0].node = NULL;
mpNodeStack->stackPtr = 1;
curr = mpRoot;
mint = GFX_REAL_MAX;
while(curr != NULL) { // +X
while( !curr->isLeaf() ) {
planedist = distanceToPlane(curr, curr->child[0]->max, ray );
getChildren(curr, ray.getOrigin(), nearChild, farChild );
// check ray direction for small plane distances
if( (planedist>-getVecEpsilon() )&&(planedist< getVecEpsilon() ) ) {
// ray origin on intersection plane
planedist = 0.0;
if(ray.getDirection()[curr->axis]>getVecEpsilon() ) {
// larger coords
curr = curr->child[1];
} else if(ray.getDirection()[curr->axis]<-getVecEpsilon() ) {
// smaller coords
curr = curr->child[0];
} else {
// paralell, order doesnt really matter are min/max/plane ok?
mpNodeStack->elem[ mpNodeStack->stackPtr ].node = curr->child[0];
mpNodeStack->elem[ mpNodeStack->stackPtr ].mindist = planedist;
mpNodeStack->elem[ mpNodeStack->stackPtr ].maxdist = maxdist;
(mpNodeStack->stackPtr)++;
curr = curr->child[1];
maxdist = planedist;
}
} else {
// normal ray
if( (planedist>maxdist) || (planedist<0.0-getVecEpsilon() ) ) {
curr = nearChild;
} else if(planedist < mindist) {
curr = farChild;
} else {
mpNodeStack->elem[ mpNodeStack->stackPtr ].node = farChild;
mpNodeStack->elem[ mpNodeStack->stackPtr ].mindist = planedist;
mpNodeStack->elem[ mpNodeStack->stackPtr ].maxdist = maxdist;
(mpNodeStack->stackPtr)++;
curr = nearChild;
maxdist = planedist;
}
}
} // +X
/* intersect with current node */
for (vector<ntlTriangle *>::iterator iter = curr->members->begin();
iter != curr->members->end(); iter++ ) {
/* check for triangle flags before intersecting */
if((!flags) || ( ((*iter)->getFlags() & flags) > 0 )) {
if( ((*iter)->getLastRay() == ray.getID() )&&((*iter)->getLastRay()>0) ) {
// was already intersected...
} else {
// we still need to intersect this triangle
gfxReal u=0.0,v=0.0, t=-1.0;
ray.intersectTriangleX( mpVertices, (*iter), t,u,v);
(*iter)->setLastRay( ray.getID() );
if( (t > 0.0) && (t<mint) ) {
mint = t;
hit = (*iter);
mintu = u; mintv = v;
}
}
} // flags check
} // +X
/* check if intersection is valid */
if( (mint>0.0) && (mint < GFX_REAL_MAX) ) {
pos = ray.getOrigin() + ray.getDirection()*mint;
if( (pos[0] >= curr->min[0]) && (pos[0] <= curr->max[0]) &&
(pos[1] >= curr->min[1]) && (pos[1] <= curr->max[1]) &&
(pos[2] >= curr->min[2]) && (pos[2] <= curr->max[2]) )
{
if(forceNonsmooth) {
// calculate triangle normal
ntlVec3Gfx e0,e1,e2;
e0 = (*mpVertices)[ hit->getPoints()[0] ];
e1 = (*mpVertices)[ hit->getPoints()[1] ];
e2 = (*mpVertices)[ hit->getPoints()[2] ];
retnormal = cross( -(e2-e0), (e1-e0) );
} else {
// calculate interpolated normal
retnormal = (*mpVertNormals)[ hit->getPoints()[0] ] * (1.0-mintu-mintv)+
(*mpVertNormals)[ hit->getPoints()[1] ]*mintu +
(*mpVertNormals)[ hit->getPoints()[2] ]*mintv;
}
normalize(retnormal);
normal = retnormal;
distance = mint;
tri = hit;
return;
}
} // +X
(mpNodeStack->stackPtr)--;
curr = mpNodeStack->elem[ mpNodeStack->stackPtr ].node;
mindist = mpNodeStack->elem[ mpNodeStack->stackPtr ].mindist;
maxdist = mpNodeStack->elem[ mpNodeStack->stackPtr ].maxdist;
} /* traverse tree */
if(mint == GFX_REAL_MAX) {
distance = -1.0;
} else {
// intersection outside the BSP bounding volumes might occur due to roundoff...
if(forceNonsmooth) {
// calculate triangle normal
ntlVec3Gfx e0,e1,e2;
e0 = (*mpVertices)[ hit->getPoints()[0] ];
e1 = (*mpVertices)[ hit->getPoints()[1] ];
e2 = (*mpVertices)[ hit->getPoints()[2] ];
retnormal = cross( -(e2-e0), (e1-e0) );
} else {
// calculate interpolated normal
retnormal = (*mpVertNormals)[ hit->getPoints()[0] ] * (1.0-mintu-mintv)+
(*mpVertNormals)[ hit->getPoints()[1] ]*mintu +
(*mpVertNormals)[ hit->getPoints()[2] ]*mintv;
}
normalize(retnormal);
normal = retnormal;
distance = mint;
tri = hit;
} // +X
return;
}
