1037 lines
25 KiB
C
1037 lines
25 KiB
C
|
/////////////////////////////////////////////
|
||
|
|
//
|
||
|
|
// Mesh Simplification Tutorial
|
||
|
|
//
|
||
|
|
// (C) by Sven Forstmann in 2014
|
||
|
|
//
|
||
|
|
// License : MIT
|
||
|
|
// http://opensource.org/licenses/MIT
|
||
|
|
//
|
||
|
|
//https://github.com/sp4cerat/Fast-Quadric-Mesh-Simplification
|
||
|
|
//
|
||
|
|
// 5/2016: Chris Rorden created minimal version for OSX/Linux/Windows compile
|
||
|
|
|
||
|
|
//#include <iostream>
|
||
|
|
//#include <stddef.h>
|
||
|
|
//#include <functional>
|
||
|
|
//#include <sys/stat.h>
|
||
|
|
//#include <stdbool.h>
|
||
|
|
#include <string.h>
|
||
|
|
//#include <ctype.h>
|
||
|
|
//#include <float.h>
|
||
|
|
#include <stdio.h>
|
||
|
|
#include <stdlib.h>
|
||
|
|
#include <map>
|
||
|
|
#include <vector>
|
||
|
|
#include <string>
|
||
|
|
#include <math.h>
|
||
|
|
#include <float.h> //FLT_EPSILON, DBL_EPSILON
|
||
|
|
|
||
|
|
#define loopi(start_l,end_l) for ( int i=start_l;i<end_l;++i )
|
||
|
|
#define loopi(start_l,end_l) for ( int i=start_l;i<end_l;++i )
|
||
|
|
#define loopj(start_l,end_l) for ( int j=start_l;j<end_l;++j )
|
||
|
|
#define loopk(start_l,end_l) for ( int k=start_l;k<end_l;++k )
|
||
|
|
|
||
|
|
struct vector3
|
||
|
|
{
|
||
|
|
double x, y, z;
|
||
|
|
};
|
||
|
|
|
||
|
|
struct vec3f
|
||
|
|
{
|
||
|
|
double x, y, z;
|
||
|
|
|
||
|
|
inline vec3f( void ) {}
|
||
|
|
|
||
|
|
//inline vec3f operator =( vector3 a )
|
||
|
|
// { vec3f b ; b.x = a.x; b.y = a.y; b.z = a.z; return b;}
|
||
|
|
|
||
|
|
inline vec3f( vector3 a )
|
||
|
|
{ x = a.x; y = a.y; z = a.z; }
|
||
|
|
|
||
|
|
inline vec3f( const double X, const double Y, const double Z )
|
||
|
|
{ x = X; y = Y; z = Z; }
|
||
|
|
|
||
|
|
inline vec3f operator + ( const vec3f& a ) const
|
||
|
|
{ return vec3f( x + a.x, y + a.y, z + a.z ); }
|
||
|
|
|
||
|
|
inline vec3f operator += ( const vec3f& a ) const
|
||
|
|
{ return vec3f( x + a.x, y + a.y, z + a.z ); }
|
||
|
|
|
||
|
|
inline vec3f operator * ( const double a ) const
|
||
|
|
{ return vec3f( x * a, y * a, z * a ); }
|
||
|
|
|
||
|
|
inline vec3f operator * ( const vec3f a ) const
|
||
|
|
{ return vec3f( x * a.x, y * a.y, z * a.z ); }
|
||
|
|
|
||
|
|
inline vec3f v3 () const
|
||
|
|
{ return vec3f( x , y, z ); }
|
||
|
|
|
||
|
|
inline vec3f operator = ( const vector3 a )
|
||
|
|
{ x=a.x;y=a.y;z=a.z;return *this; }
|
||
|
|
|
||
|
|
inline vec3f operator = ( const vec3f a )
|
||
|
|
{ x=a.x;y=a.y;z=a.z;return *this; }
|
||
|
|
|
||
|
|
inline vec3f operator / ( const vec3f a ) const
|
||
|
|
{ return vec3f( x / a.x, y / a.y, z / a.z ); }
|
||
|
|
|
||
|
|
inline vec3f operator - ( const vec3f& a ) const
|
||
|
|
{ return vec3f( x - a.x, y - a.y, z - a.z ); }
|
||
|
|
|
||
|
|
inline vec3f operator / ( const double a ) const
|
||
|
|
{ return vec3f( x / a, y / a, z / a ); }
|
||
|
|
|
||
|
|
inline double dot( const vec3f& a ) const
|
||
|
|
{ return a.x*x + a.y*y + a.z*z; }
|
||
|
|
|
||
|
|
inline vec3f cross( const vec3f& a , const vec3f& b )
|
||
|
|
{
|
||
|
|
x = a.y * b.z - a.z * b.y;
|
||
|
|
y = a.z * b.x - a.x * b.z;
|
||
|
|
z = a.x * b.y - a.y * b.x;
|
||
|
|
return *this;
|
||
|
|
}
|
||
|
|
|
||
|
|
inline double angle( const vec3f& v )
|
||
|
|
{
|
||
|
|
vec3f a = v , b = *this;
|
||
|
|
double dot = v.x*x + v.y*y + v.z*z;
|
||
|
|
double len = a.length() * b.length();
|
||
|
|
if(len==0)len=0.00001f;
|
||
|
|
double input = dot / len;
|
||
|
|
if (input<-1) input=-1;
|
||
|
|
if (input>1) input=1;
|
||
|
|
return (double) acos ( input );
|
||
|
|
}
|
||
|
|
|
||
|
|
inline double angle2( const vec3f& v , const vec3f& w )
|
||
|
|
{
|
||
|
|
vec3f a = v , b= *this;
|
||
|
|
double dot = a.x*b.x + a.y*b.y + a.z*b.z;
|
||
|
|
double len = a.length() * b.length();
|
||
|
|
if(len==0)len=1;
|
||
|
|
|
||
|
|
vec3f plane; plane.cross( b,w );
|
||
|
|
|
||
|
|
if ( plane.x * a.x + plane.y * a.y + plane.z * a.z > 0 )
|
||
|
|
return (double) -acos ( dot / len );
|
||
|
|
|
||
|
|
return (double) acos ( dot / len );
|
||
|
|
}
|
||
|
|
|
||
|
|
inline vec3f rot_x( double a )
|
||
|
|
{
|
||
|
|
double yy = cos ( a ) * y + sin ( a ) * z;
|
||
|
|
double zz = cos ( a ) * z - sin ( a ) * y;
|
||
|
|
y = yy; z = zz;
|
||
|
|
return *this;
|
||
|
|
}
|
||
|
|
inline vec3f rot_y( double a )
|
||
|
|
{
|
||
|
|
double xx = cos ( -a ) * x + sin ( -a ) * z;
|
||
|
|
double zz = cos ( -a ) * z - sin ( -a ) * x;
|
||
|
|
x = xx; z = zz;
|
||
|
|
return *this;
|
||
|
|
}
|
||
|
|
inline void clamp( double min, double max )
|
||
|
|
{
|
||
|
|
if (x<min) x=min;
|
||
|
|
if (y<min) y=min;
|
||
|
|
if (z<min) z=min;
|
||
|
|
if (x>max) x=max;
|
||
|
|
if (y>max) y=max;
|
||
|
|
if (z>max) z=max;
|
||
|
|
}
|
||
|
|
inline vec3f rot_z( double a )
|
||
|
|
{
|
||
|
|
double yy = cos ( a ) * y + sin ( a ) * x;
|
||
|
|
double xx = cos ( a ) * x - sin ( a ) * y;
|
||
|
|
y = yy; x = xx;
|
||
|
|
return *this;
|
||
|
|
}
|
||
|
|
inline vec3f invert()
|
||
|
|
{
|
||
|
|
x=-x;y=-y;z=-z;return *this;
|
||
|
|
}
|
||
|
|
inline vec3f frac()
|
||
|
|
{
|
||
|
|
return vec3f(
|
||
|
|
x-double(int(x)),
|
||
|
|
y-double(int(y)),
|
||
|
|
z-double(int(z))
|
||
|
|
);
|
||
|
|
}
|
||
|
|
|
||
|
|
inline vec3f integer()
|
||
|
|
{
|
||
|
|
return vec3f(
|
||
|
|
double(int(x)),
|
||
|
|
double(int(y)),
|
||
|
|
double(int(z))
|
||
|
|
);
|
||
|
|
}
|
||
|
|
|
||
|
|
inline double length() const
|
||
|
|
{
|
||
|
|
return (double)sqrt(x*x + y*y + z*z);
|
||
|
|
}
|
||
|
|
|
||
|
|
inline vec3f normalize( double desired_length = 1 )
|
||
|
|
{
|
||
|
|
double square = sqrt(x*x + y*y + z*z);
|
||
|
|
/*
|
||
|
|
if (square <= 0.00001f )
|
||
|
|
{
|
||
|
|
x=1;y=0;z=0;
|
||
|
|
return *this;
|
||
|
|
}*/
|
||
|
|
//double len = desired_length / square;
|
||
|
|
x/=square;y/=square;z/=square;
|
||
|
|
|
||
|
|
return *this;
|
||
|
|
}
|
||
|
|
static vec3f normalize( vec3f a );
|
||
|
|
|
||
|
|
static void random_init();
|
||
|
|
static double random_double();
|
||
|
|
static vec3f random();
|
||
|
|
|
||
|
|
static int random_number;
|
||
|
|
|
||
|
|
double random_double_01(double a){
|
||
|
|
double rnf=a*14.434252+a*364.2343+a*4213.45352+a*2341.43255+a*254341.43535+a*223454341.3523534245+23453.423412;
|
||
|
|
int rni=((int)rnf)%100000;
|
||
|
|
return double(rni)/(100000.0f-1.0f);
|
||
|
|
}
|
||
|
|
|
||
|
|
vec3f random01_fxyz(){
|
||
|
|
x=(double)random_double_01(x);
|
||
|
|
y=(double)random_double_01(y);
|
||
|
|
z=(double)random_double_01(z);
|
||
|
|
return *this;
|
||
|
|
}
|
||
|
|
|
||
|
|
};
|
||
|
|
|
||
|
|
vec3f barycentric(const vec3f &p, const vec3f &a, const vec3f &b, const vec3f &c){
|
||
|
|
vec3f v0 = b-a;
|
||
|
|
vec3f v1 = c-a;
|
||
|
|
vec3f v2 = p-a;
|
||
|
|
double d00 = v0.dot(v0);
|
||
|
|
double d01 = v0.dot(v1);
|
||
|
|
double d11 = v1.dot(v1);
|
||
|
|
double d20 = v2.dot(v0);
|
||
|
|
double d21 = v2.dot(v1);
|
||
|
|
double denom = d00*d11-d01*d01;
|
||
|
|
double v = (d11 * d20 - d01 * d21) / denom;
|
||
|
|
double w = (d00 * d21 - d01 * d20) / denom;
|
||
|
|
double u = 1.0 - v - w;
|
||
|
|
return vec3f(u,v,w);
|
||
|
|
}
|
||
|
|
|
||
|
|
vec3f interpolate(const vec3f &p, const vec3f &a, const vec3f &b, const vec3f &c, const vec3f attrs[3])
|
||
|
|
{
|
||
|
|
vec3f bary = barycentric(p,a,b,c);
|
||
|
|
vec3f out = vec3f(0,0,0);
|
||
|
|
out = out + attrs[0] * bary.x;
|
||
|
|
out = out + attrs[1] * bary.y;
|
||
|
|
out = out + attrs[2] * bary.z;
|
||
|
|
return out;
|
||
|
|
}
|
||
|
|
|
||
|
|
double min(double v1, double v2) {
|
||
|
|
return fmin(v1,v2);
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
class SymetricMatrix {
|
||
|
|
|
||
|
|
public:
|
||
|
|
|
||
|
|
// Constructor
|
||
|
|
|
||
|
|
SymetricMatrix(double c=0) { loopi(0,10) m[i] = c; }
|
||
|
|
|
||
|
|
SymetricMatrix( double m11, double m12, double m13, double m14,
|
||
|
|
double m22, double m23, double m24,
|
||
|
|
double m33, double m34,
|
||
|
|
double m44) {
|
||
|
|
m[0] = m11; m[1] = m12; m[2] = m13; m[3] = m14;
|
||
|
|
m[4] = m22; m[5] = m23; m[6] = m24;
|
||
|
|
m[7] = m33; m[8] = m34;
|
||
|
|
m[9] = m44;
|
||
|
|
}
|
||
|
|
|
||
|
|
// Make plane
|
||
|
|
|
||
|
|
SymetricMatrix(double a,double b,double c,double d)
|
||
|
|
{
|
||
|
|
m[0] = a*a; m[1] = a*b; m[2] = a*c; m[3] = a*d;
|
||
|
|
m[4] = b*b; m[5] = b*c; m[6] = b*d;
|
||
|
|
m[7 ] =c*c; m[8 ] = c*d;
|
||
|
|
m[9 ] = d*d;
|
||
|
|
}
|
||
|
|
|
||
|
|
double operator[](int c) const { return m[c]; }
|
||
|
|
|
||
|
|
// Determinant
|
||
|
|
|
||
|
|
double det( int a11, int a12, int a13,
|
||
|
|
int a21, int a22, int a23,
|
||
|
|
int a31, int a32, int a33)
|
||
|
|
{
|
||
|
|
double det = m[a11]*m[a22]*m[a33] + m[a13]*m[a21]*m[a32] + m[a12]*m[a23]*m[a31]
|
||
|
|
- m[a13]*m[a22]*m[a31] - m[a11]*m[a23]*m[a32]- m[a12]*m[a21]*m[a33];
|
||
|
|
return det;
|
||
|
|
}
|
||
|
|
|
||
|
|
const SymetricMatrix operator+(const SymetricMatrix& n) const
|
||
|
|
{
|
||
|
|
return SymetricMatrix( m[0]+n[0], m[1]+n[1], m[2]+n[2], m[3]+n[3],
|
||
|
|
m[4]+n[4], m[5]+n[5], m[6]+n[6],
|
||
|
|
m[ 7]+n[ 7], m[ 8]+n[8 ],
|
||
|
|
m[ 9]+n[9 ]);
|
||
|
|
}
|
||
|
|
|
||
|
|
SymetricMatrix& operator+=(const SymetricMatrix& n)
|
||
|
|
{
|
||
|
|
m[0]+=n[0]; m[1]+=n[1]; m[2]+=n[2]; m[3]+=n[3];
|
||
|
|
m[4]+=n[4]; m[5]+=n[5]; m[6]+=n[6]; m[7]+=n[7];
|
||
|
|
m[8]+=n[8]; m[9]+=n[9];
|
||
|
|
return *this;
|
||
|
|
}
|
||
|
|
|
||
|
|
double m[10];
|
||
|
|
};
|
||
|
|
///////////////////////////////////////////
|
||
|
|
|
||
|
|
namespace Simplify
|
||
|
|
{
|
||
|
|
// Global Variables & Strctures
|
||
|
|
enum Attributes {
|
||
|
|
NONE,
|
||
|
|
NORMAL = 2,
|
||
|
|
TEXCOORD = 4,
|
||
|
|
COLOR = 8
|
||
|
|
};
|
||
|
|
struct Triangle { int v[3];double err[4];int deleted,dirty,attr;vec3f n;vec3f uvs[3];int material; };
|
||
|
|
struct Vertex { vec3f p;int tstart,tcount;SymetricMatrix q;int border;};
|
||
|
|
struct Ref { int tid,tvertex; };
|
||
|
|
std::vector<Triangle> triangles;
|
||
|
|
std::vector<Vertex> vertices;
|
||
|
|
std::vector<Ref> refs;
|
||
|
|
std::string mtllib;
|
||
|
|
std::vector<std::string> materials;
|
||
|
|
|
||
|
|
// Helper functions
|
||
|
|
|
||
|
|
double vertex_error(SymetricMatrix q, double x, double y, double z);
|
||
|
|
double calculate_error(int id_v1, int id_v2, vec3f &p_result);
|
||
|
|
bool flipped(vec3f p,int i0,int i1,Vertex &v0,Vertex &v1,std::vector<int> &deleted);
|
||
|
|
void update_uvs(int i0,const Vertex &v,const vec3f &p,std::vector<int> &deleted);
|
||
|
|
void update_triangles(int i0,Vertex &v,std::vector<int> &deleted,int &deleted_triangles);
|
||
|
|
void update_mesh(int iteration);
|
||
|
|
void compact_mesh();
|
||
|
|
//
|
||
|
|
// Main simplification function
|
||
|
|
//
|
||
|
|
// target_count : target nr. of triangles
|
||
|
|
// agressiveness : sharpness to increase the threshold.
|
||
|
|
// 5..8 are good numbers
|
||
|
|
// more iterations yield higher quality
|
||
|
|
//
|
||
|
|
|
||
|
|
void simplify_mesh(int target_count, double agressiveness=7, bool verbose=false)
|
||
|
|
{
|
||
|
|
// init
|
||
|
|
loopi(0,triangles.size())
|
||
|
|
{
|
||
|
|
triangles[i].deleted=0;
|
||
|
|
}
|
||
|
|
|
||
|
|
// main iteration loop
|
||
|
|
int deleted_triangles=0;
|
||
|
|
std::vector<int> deleted0,deleted1;
|
||
|
|
int triangle_count=triangles.size();
|
||
|
|
//int iteration = 0;
|
||
|
|
//loop(iteration,0,100)
|
||
|
|
for (int iteration = 0; iteration < 100; iteration ++)
|
||
|
|
{
|
||
|
|
if(triangle_count-deleted_triangles<=target_count)break;
|
||
|
|
|
||
|
|
// update mesh once in a while
|
||
|
|
if(iteration%5==0)
|
||
|
|
{
|
||
|
|
update_mesh(iteration);
|
||
|
|
}
|
||
|
|
|
||
|
|
// clear dirty flag
|
||
|
|
loopi(0,triangles.size()) triangles[i].dirty=0;
|
||
|
|
|
||
|
|
//
|
||
|
|
// All triangles with edges below the threshold will be removed
|
||
|
|
//
|
||
|
|
// The following numbers works well for most models.
|
||
|
|
// If it does not, try to adjust the 3 parameters
|
||
|
|
//
|
||
|
|
double threshold = 0.000000001*pow(double(iteration+3),agressiveness);
|
||
|
|
|
||
|
|
// target number of triangles reached ? Then break
|
||
|
|
if ((verbose) && (iteration%5==0)) {
|
||
|
|
printf("iteration %d - triangles %d threshold %g\n",iteration,triangle_count-deleted_triangles, threshold);
|
||
|
|
}
|
||
|
|
|
||
|
|
// remove vertices & mark deleted triangles
|
||
|
|
loopi(0,triangles.size())
|
||
|
|
{
|
||
|
|
Triangle &t=triangles[i];
|
||
|
|
if(t.err[3]>threshold) continue;
|
||
|
|
if(t.deleted) continue;
|
||
|
|
if(t.dirty) continue;
|
||
|
|
|
||
|
|
loopj(0,3)if(t.err[j]<threshold)
|
||
|
|
{
|
||
|
|
|
||
|
|
int i0=t.v[ j ]; Vertex &v0 = vertices[i0];
|
||
|
|
int i1=t.v[(j+1)%3]; Vertex &v1 = vertices[i1];
|
||
|
|
// Border check
|
||
|
|
if(v0.border != v1.border) continue;
|
||
|
|
|
||
|
|
// Compute vertex to collapse to
|
||
|
|
vec3f p;
|
||
|
|
calculate_error(i0,i1,p);
|
||
|
|
deleted0.resize(v0.tcount); // normals temporarily
|
||
|
|
deleted1.resize(v1.tcount); // normals temporarily
|
||
|
|
// don't remove if flipped
|
||
|
|
if( flipped(p,i0,i1,v0,v1,deleted0) ) continue;
|
||
|
|
|
||
|
|
if( flipped(p,i1,i0,v1,v0,deleted1) ) continue;
|
||
|
|
|
||
|
|
if ( (t.attr & TEXCOORD) == TEXCOORD )
|
||
|
|
{
|
||
|
|
update_uvs(i0,v0,p,deleted0);
|
||
|
|
update_uvs(i0,v1,p,deleted1);
|
||
|
|
}
|
||
|
|
|
||
|
|
// not flipped, so remove edge
|
||
|
|
v0.p=p;
|
||
|
|
v0.q=v1.q+v0.q;
|
||
|
|
int tstart=refs.size();
|
||
|
|
|
||
|
|
update_triangles(i0,v0,deleted0,deleted_triangles);
|
||
|
|
update_triangles(i0,v1,deleted1,deleted_triangles);
|
||
|
|
|
||
|
|
int tcount=refs.size()-tstart;
|
||
|
|
|
||
|
|
if(tcount<=v0.tcount)
|
||
|
|
{
|
||
|
|
// save ram
|
||
|
|
if(tcount)memcpy(&refs[v0.tstart],&refs[tstart],tcount*sizeof(Ref));
|
||
|
|
}
|
||
|
|
else
|
||
|
|
// append
|
||
|
|
v0.tstart=tstart;
|
||
|
|
|
||
|
|
v0.tcount=tcount;
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
// done?
|
||
|
|
if(triangle_count-deleted_triangles<=target_count)break;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
// clean up mesh
|
||
|
|
compact_mesh();
|
||
|
|
} //simplify_mesh()
|
||
|
|
|
||
|
|
void simplify_mesh_lossless(bool verbose=false)
|
||
|
|
{
|
||
|
|
// init
|
||
|
|
loopi(0,triangles.size()) triangles[i].deleted=0;
|
||
|
|
|
||
|
|
// main iteration loop
|
||
|
|
int deleted_triangles=0;
|
||
|
|
std::vector<int> deleted0,deleted1;
|
||
|
|
int triangle_count=triangles.size();
|
||
|
|
//int iteration = 0;
|
||
|
|
//loop(iteration,0,100)
|
||
|
|
for (int iteration = 0; iteration < 9999; iteration ++)
|
||
|
|
{
|
||
|
|
// update mesh constantly
|
||
|
|
update_mesh(iteration);
|
||
|
|
// clear dirty flag
|
||
|
|
loopi(0,triangles.size()) triangles[i].dirty=0;
|
||
|
|
//
|
||
|
|
// All triangles with edges below the threshold will be removed
|
||
|
|
//
|
||
|
|
// The following numbers works well for most models.
|
||
|
|
// If it does not, try to adjust the 3 parameters
|
||
|
|
//
|
||
|
|
double threshold = DBL_EPSILON; //1.0E-3 EPS;
|
||
|
|
if (verbose) {
|
||
|
|
printf("lossless iteration %d\n", iteration);
|
||
|
|
}
|
||
|
|
|
||
|
|
// remove vertices & mark deleted triangles
|
||
|
|
loopi(0,triangles.size())
|
||
|
|
{
|
||
|
|
Triangle &t=triangles[i];
|
||
|
|
if(t.err[3]>threshold) continue;
|
||
|
|
if(t.deleted) continue;
|
||
|
|
if(t.dirty) continue;
|
||
|
|
|
||
|
|
loopj(0,3)if(t.err[j]<threshold)
|
||
|
|
{
|
||
|
|
int i0=t.v[ j ]; Vertex &v0 = vertices[i0];
|
||
|
|
int i1=t.v[(j+1)%3]; Vertex &v1 = vertices[i1];
|
||
|
|
|
||
|
|
// Border check
|
||
|
|
if(v0.border != v1.border) continue;
|
||
|
|
|
||
|
|
// Compute vertex to collapse to
|
||
|
|
vec3f p;
|
||
|
|
calculate_error(i0,i1,p);
|
||
|
|
|
||
|
|
deleted0.resize(v0.tcount); // normals temporarily
|
||
|
|
deleted1.resize(v1.tcount); // normals temporarily
|
||
|
|
|
||
|
|
// don't remove if flipped
|
||
|
|
if( flipped(p,i0,i1,v0,v1,deleted0) ) continue;
|
||
|
|
if( flipped(p,i1,i0,v1,v0,deleted1) ) continue;
|
||
|
|
|
||
|
|
if ( (t.attr & TEXCOORD) == TEXCOORD )
|
||
|
|
{
|
||
|
|
update_uvs(i0,v0,p,deleted0);
|
||
|
|
update_uvs(i0,v1,p,deleted1);
|
||
|
|
}
|
||
|
|
|
||
|
|
// not flipped, so remove edge
|
||
|
|
v0.p=p;
|
||
|
|
v0.q=v1.q+v0.q;
|
||
|
|
int tstart=refs.size();
|
||
|
|
|
||
|
|
update_triangles(i0,v0,deleted0,deleted_triangles);
|
||
|
|
update_triangles(i0,v1,deleted1,deleted_triangles);
|
||
|
|
|
||
|
|
int tcount=refs.size()-tstart;
|
||
|
|
|
||
|
|
if(tcount<=v0.tcount)
|
||
|
|
{
|
||
|
|
// save ram
|
||
|
|
if(tcount)memcpy(&refs[v0.tstart],&refs[tstart],tcount*sizeof(Ref));
|
||
|
|
}
|
||
|
|
else
|
||
|
|
// append
|
||
|
|
v0.tstart=tstart;
|
||
|
|
|
||
|
|
v0.tcount=tcount;
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
if(deleted_triangles<=0)break;
|
||
|
|
deleted_triangles=0;
|
||
|
|
} //for each iteration
|
||
|
|
// clean up mesh
|
||
|
|
compact_mesh();
|
||
|
|
} //simplify_mesh_lossless()
|
||
|
|
|
||
|
|
|
||
|
|
// Check if a triangle flips when this edge is removed
|
||
|
|
|
||
|
|
bool flipped(vec3f p,int i0,int i1,Vertex &v0,Vertex &v1,std::vector<int> &deleted)
|
||
|
|
{
|
||
|
|
|
||
|
|
loopk(0,v0.tcount)
|
||
|
|
{
|
||
|
|
Triangle &t=triangles[refs[v0.tstart+k].tid];
|
||
|
|
if(t.deleted)continue;
|
||
|
|
|
||
|
|
int s=refs[v0.tstart+k].tvertex;
|
||
|
|
int id1=t.v[(s+1)%3];
|
||
|
|
int id2=t.v[(s+2)%3];
|
||
|
|
|
||
|
|
if(id1==i1 || id2==i1) // delete ?
|
||
|
|
{
|
||
|
|
|
||
|
|
deleted[k]=1;
|
||
|
|
continue;
|
||
|
|
}
|
||
|
|
vec3f d1 = vertices[id1].p-p; d1.normalize();
|
||
|
|
vec3f d2 = vertices[id2].p-p; d2.normalize();
|
||
|
|
if(fabs(d1.dot(d2))>0.999) return true;
|
||
|
|
vec3f n;
|
||
|
|
n.cross(d1,d2);
|
||
|
|
n.normalize();
|
||
|
|
deleted[k]=0;
|
||
|
|
if(n.dot(t.n)<0.2) return true;
|
||
|
|
}
|
||
|
|
return false;
|
||
|
|
}
|
||
|
|
|
||
|
|
// update_uvs
|
||
|
|
|
||
|
|
void update_uvs(int i0,const Vertex &v,const vec3f &p,std::vector<int> &deleted)
|
||
|
|
{
|
||
|
|
loopk(0,v.tcount)
|
||
|
|
{
|
||
|
|
Ref &r=refs[v.tstart+k];
|
||
|
|
Triangle &t=triangles[r.tid];
|
||
|
|
if(t.deleted)continue;
|
||
|
|
if(deleted[k])continue;
|
||
|
|
vec3f p1=vertices[t.v[0]].p;
|
||
|
|
vec3f p2=vertices[t.v[1]].p;
|
||
|
|
vec3f p3=vertices[t.v[2]].p;
|
||
|
|
t.uvs[r.tvertex] = interpolate(p,p1,p2,p3,t.uvs);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
// Update triangle connections and edge error after a edge is collapsed
|
||
|
|
|
||
|
|
void update_triangles(int i0,Vertex &v,std::vector<int> &deleted,int &deleted_triangles)
|
||
|
|
{
|
||
|
|
vec3f p;
|
||
|
|
loopk(0,v.tcount)
|
||
|
|
{
|
||
|
|
Ref &r=refs[v.tstart+k];
|
||
|
|
Triangle &t=triangles[r.tid];
|
||
|
|
if(t.deleted)continue;
|
||
|
|
if(deleted[k])
|
||
|
|
{
|
||
|
|
t.deleted=1;
|
||
|
|
deleted_triangles++;
|
||
|
|
continue;
|
||
|
|
}
|
||
|
|
t.v[r.tvertex]=i0;
|
||
|
|
t.dirty=1;
|
||
|
|
t.err[0]=calculate_error(t.v[0],t.v[1],p);
|
||
|
|
t.err[1]=calculate_error(t.v[1],t.v[2],p);
|
||
|
|
t.err[2]=calculate_error(t.v[2],t.v[0],p);
|
||
|
|
t.err[3]=min(t.err[0],min(t.err[1],t.err[2]));
|
||
|
|
refs.push_back(r);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
// compact triangles, compute edge error and build reference list
|
||
|
|
|
||
|
|
void update_mesh(int iteration)
|
||
|
|
{
|
||
|
|
if(iteration>0) // compact triangles
|
||
|
|
{
|
||
|
|
int dst=0;
|
||
|
|
loopi(0,triangles.size())
|
||
|
|
if(!triangles[i].deleted)
|
||
|
|
{
|
||
|
|
triangles[dst++]=triangles[i];
|
||
|
|
}
|
||
|
|
triangles.resize(dst);
|
||
|
|
}
|
||
|
|
//
|
||
|
|
// Init Quadrics by Plane & Edge Errors
|
||
|
|
//
|
||
|
|
// required at the beginning ( iteration == 0 )
|
||
|
|
// recomputing during the simplification is not required,
|
||
|
|
// but mostly improves the result for closed meshes
|
||
|
|
//
|
||
|
|
if( iteration == 0 )
|
||
|
|
{
|
||
|
|
loopi(0,vertices.size())
|
||
|
|
vertices[i].q=SymetricMatrix(0.0);
|
||
|
|
|
||
|
|
loopi(0,triangles.size())
|
||
|
|
{
|
||
|
|
Triangle &t=triangles[i];
|
||
|
|
vec3f n,p[3];
|
||
|
|
loopj(0,3) p[j]=vertices[t.v[j]].p;
|
||
|
|
n.cross(p[1]-p[0],p[2]-p[0]);
|
||
|
|
n.normalize();
|
||
|
|
t.n=n;
|
||
|
|
loopj(0,3) vertices[t.v[j]].q =
|
||
|
|
vertices[t.v[j]].q+SymetricMatrix(n.x,n.y,n.z,-n.dot(p[0]));
|
||
|
|
}
|
||
|
|
loopi(0,triangles.size())
|
||
|
|
{
|
||
|
|
// Calc Edge Error
|
||
|
|
Triangle &t=triangles[i];vec3f p;
|
||
|
|
loopj(0,3) t.err[j]=calculate_error(t.v[j],t.v[(j+1)%3],p);
|
||
|
|
t.err[3]=min(t.err[0],min(t.err[1],t.err[2]));
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
// Init Reference ID list
|
||
|
|
loopi(0,vertices.size())
|
||
|
|
{
|
||
|
|
vertices[i].tstart=0;
|
||
|
|
vertices[i].tcount=0;
|
||
|
|
}
|
||
|
|
loopi(0,triangles.size())
|
||
|
|
{
|
||
|
|
Triangle &t=triangles[i];
|
||
|
|
loopj(0,3) vertices[t.v[j]].tcount++;
|
||
|
|
}
|
||
|
|
int tstart=0;
|
||
|
|
loopi(0,vertices.size())
|
||
|
|
{
|
||
|
|
Vertex &v=vertices[i];
|
||
|
|
v.tstart=tstart;
|
||
|
|
tstart+=v.tcount;
|
||
|
|
v.tcount=0;
|
||
|
|
}
|
||
|
|
|
||
|
|
// Write References
|
||
|
|
refs.resize(triangles.size()*3);
|
||
|
|
loopi(0,triangles.size())
|
||
|
|
{
|
||
|
|
Triangle &t=triangles[i];
|
||
|
|
loopj(0,3)
|
||
|
|
{
|
||
|
|
Vertex &v=vertices[t.v[j]];
|
||
|
|
refs[v.tstart+v.tcount].tid=i;
|
||
|
|
refs[v.tstart+v.tcount].tvertex=j;
|
||
|
|
v.tcount++;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
// Identify boundary : vertices[].border=0,1
|
||
|
|
if( iteration == 0 )
|
||
|
|
{
|
||
|
|
std::vector<int> vcount,vids;
|
||
|
|
|
||
|
|
loopi(0,vertices.size())
|
||
|
|
vertices[i].border=0;
|
||
|
|
|
||
|
|
loopi(0,vertices.size())
|
||
|
|
{
|
||
|
|
Vertex &v=vertices[i];
|
||
|
|
vcount.clear();
|
||
|
|
vids.clear();
|
||
|
|
loopj(0,v.tcount)
|
||
|
|
{
|
||
|
|
int k=refs[v.tstart+j].tid;
|
||
|
|
Triangle &t=triangles[k];
|
||
|
|
loopk(0,3)
|
||
|
|
{
|
||
|
|
int ofs=0,id=t.v[k];
|
||
|
|
while(ofs<vcount.size())
|
||
|
|
{
|
||
|
|
if(vids[ofs]==id)break;
|
||
|
|
ofs++;
|
||
|
|
}
|
||
|
|
if(ofs==vcount.size())
|
||
|
|
{
|
||
|
|
vcount.push_back(1);
|
||
|
|
vids.push_back(id);
|
||
|
|
}
|
||
|
|
else
|
||
|
|
vcount[ofs]++;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
loopj(0,vcount.size()) if(vcount[j]==1)
|
||
|
|
vertices[vids[j]].border=1;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
// Finally compact mesh before exiting
|
||
|
|
|
||
|
|
void compact_mesh()
|
||
|
|
{
|
||
|
|
int dst=0;
|
||
|
|
loopi(0,vertices.size())
|
||
|
|
{
|
||
|
|
vertices[i].tcount=0;
|
||
|
|
}
|
||
|
|
loopi(0,triangles.size())
|
||
|
|
if(!triangles[i].deleted)
|
||
|
|
{
|
||
|
|
Triangle &t=triangles[i];
|
||
|
|
triangles[dst++]=t;
|
||
|
|
loopj(0,3)vertices[t.v[j]].tcount=1;
|
||
|
|
}
|
||
|
|
triangles.resize(dst);
|
||
|
|
dst=0;
|
||
|
|
loopi(0,vertices.size())
|
||
|
|
if(vertices[i].tcount)
|
||
|
|
{
|
||
|
|
vertices[i].tstart=dst;
|
||
|
|
vertices[dst].p=vertices[i].p;
|
||
|
|
dst++;
|
||
|
|
}
|
||
|
|
loopi(0,triangles.size())
|
||
|
|
{
|
||
|
|
Triangle &t=triangles[i];
|
||
|
|
loopj(0,3)t.v[j]=vertices[t.v[j]].tstart;
|
||
|
|
}
|
||
|
|
vertices.resize(dst);
|
||
|
|
}
|
||
|
|
|
||
|
|
// Error between vertex and Quadric
|
||
|
|
|
||
|
|
double vertex_error(SymetricMatrix q, double x, double y, double z)
|
||
|
|
{
|
||
|
|
return q[0]*x*x + 2*q[1]*x*y + 2*q[2]*x*z + 2*q[3]*x + q[4]*y*y
|
||
|
|
+ 2*q[5]*y*z + 2*q[6]*y + q[7]*z*z + 2*q[8]*z + q[9];
|
||
|
|
}
|
||
|
|
|
||
|
|
// Error for one edge
|
||
|
|
|
||
|
|
double calculate_error(int id_v1, int id_v2, vec3f &p_result)
|
||
|
|
{
|
||
|
|
// compute interpolated vertex
|
||
|
|
|
||
|
|
SymetricMatrix q = vertices[id_v1].q + vertices[id_v2].q;
|
||
|
|
bool border = vertices[id_v1].border & vertices[id_v2].border;
|
||
|
|
double error=0;
|
||
|
|
double det = q.det(0, 1, 2, 1, 4, 5, 2, 5, 7);
|
||
|
|
if ( det != 0 && !border )
|
||
|
|
{
|
||
|
|
|
||
|
|
// q_delta is invertible
|
||
|
|
p_result.x = -1/det*(q.det(1, 2, 3, 4, 5, 6, 5, 7 , 8)); // vx = A41/det(q_delta)
|
||
|
|
p_result.y = 1/det*(q.det(0, 2, 3, 1, 5, 6, 2, 7 , 8)); // vy = A42/det(q_delta)
|
||
|
|
p_result.z = -1/det*(q.det(0, 1, 3, 1, 4, 6, 2, 5, 8)); // vz = A43/det(q_delta)
|
||
|
|
|
||
|
|
error = vertex_error(q, p_result.x, p_result.y, p_result.z);
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
// det = 0 -> try to find best result
|
||
|
|
vec3f p1=vertices[id_v1].p;
|
||
|
|
vec3f p2=vertices[id_v2].p;
|
||
|
|
vec3f p3=(p1+p2)/2;
|
||
|
|
double error1 = vertex_error(q, p1.x,p1.y,p1.z);
|
||
|
|
double error2 = vertex_error(q, p2.x,p2.y,p2.z);
|
||
|
|
double error3 = vertex_error(q, p3.x,p3.y,p3.z);
|
||
|
|
error = min(error1, min(error2, error3));
|
||
|
|
if (error1 == error) p_result=p1;
|
||
|
|
if (error2 == error) p_result=p2;
|
||
|
|
if (error3 == error) p_result=p3;
|
||
|
|
}
|
||
|
|
return error;
|
||
|
|
}
|
||
|
|
|
||
|
|
char *trimwhitespace(char *str)
|
||
|
|
{
|
||
|
|
char *end;
|
||
|
|
|
||
|
|
// Trim leading space
|
||
|
|
while(isspace((unsigned char)*str)) str++;
|
||
|
|
|
||
|
|
if(*str == 0) // All spaces?
|
||
|
|
return str;
|
||
|
|
|
||
|
|
// Trim trailing space
|
||
|
|
end = str + strlen(str) - 1;
|
||
|
|
while(end > str && isspace((unsigned char)*end)) end--;
|
||
|
|
|
||
|
|
// Write new null terminator
|
||
|
|
*(end+1) = 0;
|
||
|
|
|
||
|
|
return str;
|
||
|
|
}
|
||
|
|
|
||
|
|
//Option : Load OBJ
|
||
|
|
void load_obj(const char* filename, bool process_uv=false){
|
||
|
|
vertices.clear();
|
||
|
|
triangles.clear();
|
||
|
|
//printf ( "Loading Objects %s ... \n",filename);
|
||
|
|
FILE* fn;
|
||
|
|
if(filename==NULL) return ;
|
||
|
|
if((char)filename[0]==0) return ;
|
||
|
|
if ((fn = fopen(filename, "rb")) == NULL)
|
||
|
|
{
|
||
|
|
printf ( "File %s not found!\n" ,filename );
|
||
|
|
return;
|
||
|
|
}
|
||
|
|
char line[1000];
|
||
|
|
memset ( line,0,1000 );
|
||
|
|
int vertex_cnt = 0;
|
||
|
|
int material = -1;
|
||
|
|
std::map<std::string, int> material_map;
|
||
|
|
std::vector<vec3f> uvs;
|
||
|
|
std::vector<std::vector<int> > uvMap;
|
||
|
|
|
||
|
|
while(fgets( line, 1000, fn ) != NULL)
|
||
|
|
{
|
||
|
|
Vertex v;
|
||
|
|
vec3f uv;
|
||
|
|
|
||
|
|
if (strncmp(line, "mtllib", 6) == 0)
|
||
|
|
{
|
||
|
|
mtllib = trimwhitespace(&line[7]);
|
||
|
|
}
|
||
|
|
if (strncmp(line, "usemtl", 6) == 0)
|
||
|
|
{
|
||
|
|
std::string usemtl = trimwhitespace(&line[7]);
|
||
|
|
if (material_map.find(usemtl) == material_map.end())
|
||
|
|
{
|
||
|
|
material_map[usemtl] = materials.size();
|
||
|
|
materials.push_back(usemtl);
|
||
|
|
}
|
||
|
|
material = material_map[usemtl];
|
||
|
|
}
|
||
|
|
|
||
|
|
if ( line[0] == 'v' && line[1] == 't' )
|
||
|
|
{
|
||
|
|
if ( line[2] == ' ' )
|
||
|
|
if(sscanf(line,"vt %lf %lf",
|
||
|
|
&uv.x,&uv.y)==2)
|
||
|
|
{
|
||
|
|
uv.z = 0;
|
||
|
|
uvs.push_back(uv);
|
||
|
|
} else
|
||
|
|
if(sscanf(line,"vt %lf %lf %lf",
|
||
|
|
&uv.x,&uv.y,&uv.z)==3)
|
||
|
|
{
|
||
|
|
uvs.push_back(uv);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
else if ( line[0] == 'v' )
|
||
|
|
{
|
||
|
|
if ( line[1] == ' ' )
|
||
|
|
if(sscanf(line,"v %lf %lf %lf",
|
||
|
|
&v.p.x, &v.p.y, &v.p.z)==3)
|
||
|
|
{
|
||
|
|
vertices.push_back(v);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
int integers[9];
|
||
|
|
if ( line[0] == 'f' )
|
||
|
|
{
|
||
|
|
Triangle t;
|
||
|
|
bool tri_ok = false;
|
||
|
|
bool has_uv = false;
|
||
|
|
|
||
|
|
if(sscanf(line,"f %d %d %d",
|
||
|
|
&integers[0],&integers[1],&integers[2])==3)
|
||
|
|
{
|
||
|
|
tri_ok = true;
|
||
|
|
}else
|
||
|
|
if(sscanf(line,"f %d// %d// %d//",
|
||
|
|
&integers[0],&integers[1],&integers[2])==3)
|
||
|
|
{
|
||
|
|
tri_ok = true;
|
||
|
|
}else
|
||
|
|
if(sscanf(line,"f %d//%d %d//%d %d//%d",
|
||
|
|
&integers[0],&integers[3],
|
||
|
|
&integers[1],&integers[4],
|
||
|
|
&integers[2],&integers[5])==6)
|
||
|
|
{
|
||
|
|
tri_ok = true;
|
||
|
|
}else
|
||
|
|
if(sscanf(line,"f %d/%d/%d %d/%d/%d %d/%d/%d",
|
||
|
|
&integers[0],&integers[6],&integers[3],
|
||
|
|
&integers[1],&integers[7],&integers[4],
|
||
|
|
&integers[2],&integers[8],&integers[5])==9)
|
||
|
|
{
|
||
|
|
tri_ok = true;
|
||
|
|
has_uv = true;
|
||
|
|
}else // Add Support for v/vt only meshes
|
||
|
|
if (sscanf(line, "f %d/%d %d/%d %d/%d",
|
||
|
|
&integers[0], &integers[6],
|
||
|
|
&integers[1], &integers[7],
|
||
|
|
&integers[2], &integers[8]) == 6)
|
||
|
|
{
|
||
|
|
tri_ok = true;
|
||
|
|
has_uv = true;
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
printf("unrecognized sequence\n");
|
||
|
|
printf("%s\n",line);
|
||
|
|
while(1);
|
||
|
|
}
|
||
|
|
if ( tri_ok )
|
||
|
|
{
|
||
|
|
t.v[0] = integers[0]-1-vertex_cnt;
|
||
|
|
t.v[1] = integers[1]-1-vertex_cnt;
|
||
|
|
t.v[2] = integers[2]-1-vertex_cnt;
|
||
|
|
t.attr = 0;
|
||
|
|
|
||
|
|
if ( process_uv && has_uv )
|
||
|
|
{
|
||
|
|
std::vector<int> indices;
|
||
|
|
indices.push_back(integers[6]-1-vertex_cnt);
|
||
|
|
indices.push_back(integers[7]-1-vertex_cnt);
|
||
|
|
indices.push_back(integers[8]-1-vertex_cnt);
|
||
|
|
uvMap.push_back(indices);
|
||
|
|
t.attr |= TEXCOORD;
|
||
|
|
}
|
||
|
|
|
||
|
|
t.material = material;
|
||
|
|
//geo.triangles.push_back ( tri );
|
||
|
|
triangles.push_back(t);
|
||
|
|
//state_before = state;
|
||
|
|
//state ='f';
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
if ( process_uv && uvs.size() )
|
||
|
|
{
|
||
|
|
loopi(0,triangles.size())
|
||
|
|
{
|
||
|
|
loopj(0,3)
|
||
|
|
triangles[i].uvs[j] = uvs[uvMap[i][j]];
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
fclose(fn);
|
||
|
|
|
||
|
|
//printf("load_obj: vertices = %lu, triangles = %lu, uvs = %lu\n", vertices.size(), triangles.size(), uvs.size() );
|
||
|
|
} // load_obj()
|
||
|
|
|
||
|
|
// Optional : Store as OBJ
|
||
|
|
|
||
|
|
void write_obj(const char* filename)
|
||
|
|
{
|
||
|
|
FILE *file=fopen(filename, "w");
|
||
|
|
int cur_material = -1;
|
||
|
|
bool has_uv = (triangles.size() && (triangles[0].attr & TEXCOORD) == TEXCOORD);
|
||
|
|
|
||
|
|
if (!file)
|
||
|
|
{
|
||
|
|
printf("write_obj: can't write data file \"%s\".\n", filename);
|
||
|
|
exit(0);
|
||
|
|
}
|
||
|
|
if (!mtllib.empty())
|
||
|
|
{
|
||
|
|
fprintf(file, "mtllib %s\n", mtllib.c_str());
|
||
|
|
}
|
||
|
|
loopi(0,vertices.size())
|
||
|
|
{
|
||
|
|
//fprintf(file, "v %lf %lf %lf\n", vertices[i].p.x,vertices[i].p.y,vertices[i].p.z);
|
||
|
|
fprintf(file, "v %g %g %g\n", vertices[i].p.x,vertices[i].p.y,vertices[i].p.z); //more compact: remove trailing zeros
|
||
|
|
}
|
||
|
|
if (has_uv)
|
||
|
|
{
|
||
|
|
loopi(0,triangles.size()) if(!triangles[i].deleted)
|
||
|
|
{
|
||
|
|
fprintf(file, "vt %g %g\n", triangles[i].uvs[0].x, triangles[i].uvs[0].y);
|
||
|
|
fprintf(file, "vt %g %g\n", triangles[i].uvs[1].x, triangles[i].uvs[1].y);
|
||
|
|
fprintf(file, "vt %g %g\n", triangles[i].uvs[2].x, triangles[i].uvs[2].y);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
int uv = 1;
|
||
|
|
loopi(0,triangles.size()) if(!triangles[i].deleted)
|
||
|
|
{
|
||
|
|
if (triangles[i].material != cur_material)
|
||
|
|
{
|
||
|
|
cur_material = triangles[i].material;
|
||
|
|
fprintf(file, "usemtl %s\n", materials[triangles[i].material].c_str());
|
||
|
|
}
|
||
|
|
if (has_uv)
|
||
|
|
{
|
||
|
|
fprintf(file, "f %d/%d %d/%d %d/%d\n", triangles[i].v[0]+1, uv, triangles[i].v[1]+1, uv+1, triangles[i].v[2]+1, uv+2);
|
||
|
|
uv += 3;
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
fprintf(file, "f %d %d %d\n", triangles[i].v[0]+1, triangles[i].v[1]+1, triangles[i].v[2]+1);
|
||
|
|
}
|
||
|
|
//fprintf(file, "f %d// %d// %d//\n", triangles[i].v[0]+1, triangles[i].v[1]+1, triangles[i].v[2]+1); //more compact: remove trailing zeros
|
||
|
|
}
|
||
|
|
fclose(file);
|
||
|
|
}
|
||
|
|
};
|
||
|
|
///////////////////////////////////////////
|