void ParticleSystem::RenderLightning()
{
glUseProgram(m_lshader);
glEnableVertexAttribArray(vtxpos);
//Initiate random gen
std::random_device rd;
std::mt19937 mt(rd());
std::uniform_int_distribution<int32_t> dist(1, m_vertices.size());
std::uniform_real_distribution<float> distf(1.0f, 5.0f);
glLineWidth(distf(mt));
glDrawArrays(GL_LINE_STRIP, 0, dist(mt));
glDisableVertexAttribArray(vtxpos);
}
void C_mapDataToCodes(double *data, double *codes,
int *pncodes, int *pnd, int *pp,
int *nnCodes, double *nnDists,
int *dist){
int ncodes = *pncodes, nd = *pnd, p = *pp;
int i, cd, counter, minid;
double tmp, mindist;
double (*distf)(double*,double*,int,int,int);
if(*dist == 1){
distf = &manh;
} else if (*dist == 2){
distf = &eucl;
} else if (*dist == 3){
distf = &chebyshev;
} else if (*dist == 4){
distf = &cosine;
} else {
distf = &eucl;
}
/* i is a counter over objects in data, cd is a counter over SOM
units, p is the number of columns, nd is the number of datapoints
and ncodes is the number of SOM units*/
counter = -1;
for (i = 0; i < nd; i++) {
minid = -1;
mindist = DBL_MAX;
for (cd = 0; cd < ncodes; cd++) {
tmp = distf(&data[i], &codes[cd], p, nd, ncodes);
//Rprintf("\ndist: %f",tmp2);
if(tmp < mindist){
mindist = tmp;
minid = cd;
}
}
nnCodes[++counter] = minid+1;
nnDists[counter] = mindist;
}
}
void C_SOM(double *data,
double *codes,
double *nhbrdist,
double *alphas, double *radii,
double *xdists, /* working arrays */
Sint *pn, Sint *ppx,
Sint *pncodes, Sint *prlen,
Sint *dist)
{
int n = *pn, px = *ppx, ncodes = *pncodes, rlen = *prlen;
int cd, i, j, k, nearest, niter;
double tmp, threshold, alpha, thresholdStep;
double change;
double (*distf)(double*,double*,int,int,int);
if(*dist == 1){
distf = &manh;
} else if (*dist == 2){
distf = &eucl;
} else if (*dist == 3){
distf = &chebyshev;
} else if (*dist == 4){
distf = &cosine;
} else {
distf = &eucl;
}
RANDIN;
niter = rlen * n;
threshold = radii[0];
thresholdStep = (radii[0] - radii[1]) / (double) niter;
change = 1.0;
for (k = 0; k < niter; k++) {
if(k%n == 0){
if(change < 1){
k = niter;
}
change = 0.0;
}
/* i is a counter over objects in data, cd is a counter over units
in the map, and j is a counter over variables */
i = (int)(n * UNIF); /* Select a random sample */
/*Rprintf("\ni: %d\n",i+1);
for (j = 0; j < px; j++) {
Rprintf(" j%d: %f",j,data[i*px + j]);
}*/
nearest = 0;
/* calculate distances in x and y spaces, and keep track of the
nearest code */
for (cd = 0; cd < ncodes; cd++) {
xdists[cd] = distf(&data[i], &codes[cd], px, n, ncodes);
if (xdists[cd] < xdists[nearest]) nearest = cd;
}
if (threshold < 1.0) threshold = 0.5;
alpha = alphas[0] - (alphas[0] - alphas[1]) * (double)k/(double)niter;
for (cd = 0; cd < ncodes; cd++) {
if(nhbrdist[cd + ncodes*nearest] > threshold) continue;
for(j = 0; j < px; j++) {
tmp = data[i + j*n] - codes[cd + j*ncodes];
change += abs(tmp);
codes[cd + j*ncodes] += tmp * alpha;
}
}
threshold -= thresholdStep;
}
RANDOUT;
}
