// Compute per-vertex normals
void TriMesh::need_normals()
{
if (normals.size() == vertices.size())
return;
need_faces();
dprintf(stderr, "Computing normals... "); dflush(stderr);
normals.clear();
normals.resize(vertices.size());
int nf = faces.size(), nv = vertices.size(), i;
for (i = 0; i < nf; i++) {
const point &p0 = vertices[faces[i][0]];
const point &p1 = vertices[faces[i][1]];
const point &p2 = vertices[faces[i][2]];
vec a = p0-p1, b = p1-p2, c = p2-p0;
float l2a = len2(a), l2b = len2(b), l2c = len2(c);
vec facenormal = a CROSS b;
normals[faces[i][0]] += facenormal * (1.0f / (l2a * l2c));
normals[faces[i][1]] += facenormal * (1.0f / (l2b * l2a));
normals[faces[i][2]] += facenormal * (1.0f / (l2c * l2b));
}
for (i = 0; i < nv; i++)
normalize(normals[i]);
dprintf(stderr, "Done.\n");
}
int isProperPipe(char** args){
int size = len2(args);
if(countPipes(args) != 1){ //Only a single pipe symbol for 2-stage pipeline
return 0;
}
if(compareStrings(args[0], "|")|| compareStrings(args[size - 1], "|")){
return 0; //Make sure pipes aren't in front or back.
}
return 1;
}
void Vector3Util::Clamp(Vector3& vect,Scalar length)
{
Scalar vecLength = len2(vect);
if(vecLength <= length * length)
{
return;
}
vect *= length / sqrt(vecLength);
}
void Vector3Util::Normalize_s(Vector3& vect)
{
Scalar vecLength = len2(vect);
if(vecLength == 0)
{
return;
}
vect /= sqrt(vecLength);
}
int main()
{
printf("Length is %d \n", len(myarray, "char") );
printf("Length is %d \n", len2(myarray) );
return 0;
}
/*
int isRedirection()
Description:
Tells whether or not a command uses redirections.
args:
char** args
Array of tokens
return:
1 if redirections, 0 elsewise.
*/
int isRedirection(char** args){
for(int i = 0; i < len2(args); i++){
if(args[i][0] == '>' || args[i][0] == '<'){
return 1;
}else{
continue;
}
}
return 0;
}
void Vector3Util::SetLength_s(Vector3& vect, Scalar length)
{
Scalar vecLength = len2(vect);
if(vecLength == 0)
{
return;
}
vect *= length / sqrt(vecLength);
}
/*
int isProperRedirection()
Description:
Tells whether or not a command is a functioning redirection.
args:
char** args
Array of tokens
return:
1 if true, 0 if false.
*/
int isProperRedirection(char** args){
int size = len2(args);
if(countRedirections(args) > 2){
return 0;
}
if(compareStrings(args[0],"<") || compareStrings(args[0],">") ||
compareStrings(args[size - 1],"<") || compareStrings(args[size - 1],">"))
{
return 0;
}
return 1;
}
Vector3 Vector3Util::ToNormalized_s(const Vector3& vect)
{
Scalar vecLength = len2(vect);
if(vecLength == 0)
{
return vect;
}
vecLength = sqrt(vecLength);
return Vector3(vect.x / vecLength, vect.y / vecLength, vect.z / vecLength);
}
int main()
{
struct node *start1;
struct node *start2;
int l1,l2,x;
start1=inputList1();
start2=inputList2();
l1=len1(start1);
l2=len2(start2);
x=findintersection(start1, l1, start2, l2);
if(x==0)
printf("\nNo intersection point between the two given lists\n");
else
printf("\nIntersection node is %d\n", x);
}
float len2( const moon9::vec3 &a, const moon9::vec3 &b )
{
return len2( b - a );
}
double len()
{
return sqrt(len2());
}
// square of distance between two vectors
pType dis2(const Point & p, const Point & q) { return len2(p - q); }
// Smooth the mesh geometry.
// XXX - this is perhaps not a great way to do this,
// but it seems to work better than most other things I've tried...
void smooth_mesh(TriMesh *themesh, float sigma)
{
themesh->need_faces();
diffuse_normals(themesh, 0.5f * sigma);
int nv = themesh->vertices.size();
int nf = themesh->faces.size();
dprintf("\rSmoothing... ");
timestamp t = now();
float invsigma2 = 1.0f / sqr(sigma);
vector<point> dflt(nv), dflt2(nv);
#pragma omp parallel
{
// Thread-local flags
vector<unsigned> flags(nv);
unsigned flag_curr = 0;
// Main filtering step
#pragma omp for
for (int i = 0; i < nv; i++) {
diffuse_vert_field(themesh, flags, flag_curr,
AccumVec<vec>(themesh->vertices),
i, invsigma2, dflt[i]);
// Just keep the displacement
dflt[i] -= themesh->vertices[i];
}
// Slightly better small-neighborhood approximation
#pragma omp for
for (int i = 0; i < nf; i++) {
point c = themesh->vertices[themesh->faces[i][0]] +
themesh->vertices[themesh->faces[i][1]] +
themesh->vertices[themesh->faces[i][2]];
c /= 3.0f;
for (int j = 0; j < 3; j++) {
int v = themesh->faces[i][j];
vec d = 0.5f * (c - themesh->vertices[v]);
dflt[v] += themesh->cornerareas[i][j] /
themesh->pointareas[themesh->faces[i][j]] *
exp(-0.5f * invsigma2 * len2(d)) * d;
}
}
// Filter displacement field
#pragma omp for
for (int i = 0; i < nv; i++) {
diffuse_vert_field(themesh, flags, flag_curr,
AccumVec<point>(dflt),
i, invsigma2, dflt2[i]);
}
// Update vertex positions
#pragma omp for
for (int i = 0; i < nv; i++)
themesh->vertices[i] += dflt[i] - dflt2[i]; // second Laplacian
} // #pragma omp parallel
dprintf("Done. Filtering took %f sec.\n", now() - t);
}
float Vector2::len() const {
return sqrt(len2());
}
float len() const{ return sqrtf( len2() ); };
const T len() const noexcept
{
return sqrt(len2());
}