glm::vec3 SpecularReflectionBxDF::EvaluateScatteredEnergy(const glm::vec3 &wo, const glm::vec3 &wi, float& pdf) const
{
pdf = PDF(wo, wi);
if(isPerfectReflective(wo,wi))
return reflection_color;
else
return glm::vec3(0);
}
RGBColour BxDF::Sample_F(const Vector3& p_wo, Vector3& p_wi, float p_u1, float p_u2, float& pdf) const {
/* Cosine-sample the hempisphere, flipping the direction if necessary */
p_wi = MonteCarlo::CosineSampleHemisphere(p_u1, p_u2);
if (p_wo.z < 0.0f) p_wi.z *= -1.f;
pdf = PDF(p_wo, p_wi);
return F(p_wo, p_wi);
}
glm::vec3 BxDF::SampleAndEvaluateScatteredEnergy(const glm::vec3 &wo, glm::vec3 &wi_ret, float rand1, float rand2, float &pdf_ret) const
{
glm::vec3 tmp = la::UnifSampleDisc(rand1, rand2);
tmp.z = sqrtf(std::max(0.f, 1.f - tmp.x*tmp.x - tmp.y*tmp.y));
if (wo.z < 0.f) tmp.z *= -1.f;
wi_ret = tmp;
pdf_ret = PDF(wo, wi_ret);
return EvaluateScatteredEnergy(wo, wi_ret);
}
/*PDF does *not* return _PDF. It returns a vector of alternating slopes and
* intercepts for the contained LinearSpaces.*/
LinearSpaceSource::ublas_vec_t LinearSpaceSource::PDF() const{
ublas_vec_t PDF(_Space->size()*2);
field_t::const_iterator SIter = _Space->begin();
ublas_vec_t::iterator pdfIter = PDF.begin();
for( ; SIter != _Space->end(); ++SIter, ++pdfIter ){
*pdfIter = SIter->slope();
++pdfIter;
*pdfIter = SIter->intercept();
}
return PDF;
}
Float pdf(const BSDFSamplingRecord &bRec, EMeasure measure) const {
if (measure != ESolidAngle ||
Frame::cosTheta(bRec.wi) <= 0 ||
Frame::cosTheta(bRec.wo) <= 0 ||
((bRec.component != -1 && bRec.component != 0) ||
!(bRec.typeMask & EGlossyReflection)))
return 0.0f;
/* Calculate the reflection half-vector */
Vector H = normalize(bRec.wo+bRec.wi);
return PDF(H) / (4 * absDot(bRec.wo, H));
}
glm::vec3 BxDF::SampleAndEvaluateScatteredEnergy(const glm::vec3 &wo, glm::vec3 &wi_ret, float rand1, float rand2, float &pdf_ret) const
{
//TODO
rand1 *= TWO_PI;
rand2 *= PI * .5f;
float x( cosf( rand1 ) * sinf( rand2 ) );
float y( sinf( rand1 ) * sinf( rand2 ) );
float z( cosf( rand2 ) );
wi_ret = glm::vec3( x, y, z );
pdf_ret = PDF( wo, wi_ret );
return EvaluateScatteredEnergy( wo, wi_ret );
}
glm::vec3 BlinnMicrofacetBxDF::SampleAndEvaluateScatteredEnergy(const glm::vec3 &wo, glm::vec3 &wi_ret, float rand1, float rand2, float &pdf_ret) const{
float cos_theta( powf( rand1, 1.f / ( exponent + 1.f ) ) );
float sin_theta( sqrtf( fmaxf( 0.f, 1.f - cos_theta * cos_theta ) ) );
float phi( rand2 * TWO_PI );
float cos_phi( cosf( phi ) );
float sin_phi( sinf( phi ) );
glm::vec3 wh( sin_theta * cos_phi, sin_theta * sin_phi, cos_theta );
float woDwh( glm::dot( wo, wh ) );
if( woDwh < 0.f ) wh = -wh;
wi_ret = -wo + 2.f * woDwh * wh;
pdf_ret = PDF( wo, wi_ret );
return EvaluateScatteredEnergy( wo, wi_ret );
}
float V(float t) {
float cdf = CDF(t);
return (cdf == 0) ? 0 : PDF(t) / cdf;
}
void demodulation(void)
{
int i, j, u, v, index, value, rxword[n], bi_rxword[n*p];
unsigned long int mask;
float sum, proba[pointNum], maxValue;
float Pr[p][2];
//initializ
for(u=0;u<q;u++)
for(v=0;v<n;v++)
RM[u][v]=0;
//cal PDF
for(i=0;i<n;i++)
{
for(j=0;j<p;j++)
{
sum=0;
for(u=0;u<pointNum;u++)
{
proba[u]=PDF(i*p+j,u);
sum+=proba[u];
}
Pr[j][0]=proba[0]/sum; //proba-->00 0
Pr[j][1]=proba[1]/sum; //proba-->01 1
}
j=0;
for(int z=0;z<pointNum;z++)
for(u=0;u<pointNum;u++)
for(v=0;v<pointNum;v++)
for(int x=0;x<pointNum;x++)
for(int y=0;y<pointNum;y++)
for(int h=0;h<pointNum;h++)
{
RM[j][i]=(Pr[0][h]*Pr[1][y]*Pr[2][x]*Pr[3][v]*Pr[4][u]*Pr[5][z]);
j++;
}
}
//find the rxword and bi_rxword
for(j=0;j<n;j++)
{
maxValue=RM[0][j];
index=0;
for(i=1;i<q;i++)
if(maxValue<RM[i][j])
{
maxValue=RM[i][j];
index=i;
}
rxword[j]=root[index];
}
////convert to binary
//for(u=0;u<n*p;u++) //n*4
// bi_rxword[u]=0;
//for(u=0;u<n;u++) //n
//{
// value=rxword[u];
// mask=1;
// for(v=0;v<p;v++)
// {
// if((value & mask)>0)
// bi_rxword[p*u+v]=1;
// else
// bi_rxword[p*u+v]=0;
// mask=mask<<1;
// }
//}
//*********KV optimal rule**************
float score_1=0;
float score_2=0;
for(i=0;i<n;i++)
{
for(j=0;j<q;j++)
{
if( codeword[i]==root[j] )
score_1+=RM[j][i];
if (RM[j][i])
score_2+=(RM[j][i]*RM[j][i]);
}
}
score_2=weiz*score_2;
score_2 = pow( score_2,0.5f );
if( score_1>score_2 )
{
for(u=0;u<n;u++)
dec_codeword[u]=codeword[u];
//for(u=0;u<n*p;u++)
// dec_bicodeword[u]=bi_codeword[u];
}
else
{
for(u=0;u<n;u++)
dec_codeword[u]=rxword[u];
//for(u=0;u<n*p;u++)
// dec_bicodeword[u]=bi_rxword[u];
}
//*************************************
/*
for(j=0;j<n;j++)
{
maxValue=RM[0][j];
index=0;
for(i=1;i<q;i++)
if(maxValue<RM[i][j])
{
maxValue=RM[i][j];
index=i;
}
rxword[j]=root[index];
}
epcount1=0;
for(i=0;i<n;i++) //n
if(rxword[i]!=codeword[i])
epcount1++;
*/
// printf("\n\nepcount1=%d\n", epcount1);
/* //*****debug**********
printf("\n\ncodeword");
for(v=0;v<n;v++)
printf("\t%d",codeword[v]);
printf("\n\nrxword\t");
for(v=0;v<n;v++)
printf("\t%d",rxword[v]);
printf("\n\n");
for(v=0;v<n*p/4;v++)
printf("\t(%f,%f,%f,%f)",rx_symbol[v*2+0][0],rx_symbol[v*2+0][1],rx_symbol[v*2+1][0],rx_symbol[v*2+1][0]);
printf("\n\n");
for(u=0;u<q;u++)
{
printf("\n");
printf("\t%d",root[u]);
for(v=0;v<n;v++)
printf("\t%f",RM[u][v]);
}
printf("\n\n");
*/ //*******************
}
