Modify the coordinate z In the OBJ 3D model file to the opposite number.

The specific method is: open an OBJ file and findV X Y ZAnd then the Z string is processed as a symbol:

If it is "-", delete the symbol directly. If it is not "-" And the Z value is not 0, add "-" to the string of Z "-".

Example (original file box. OBJ)

#
# Object box01
#

V-39.306316-32.828358-29.183971
V-39.306316 33.259296-29.183971
V 39.726025 33.259296-29.183971
V 39.726025-32.828358-29.183971
V-39.306316-32.828358 26.914204
V 39.726025-32.828358 26.914204
V 39.726025 33.259296 26.914204
V-39.306316 33.259296 26.914204

-----------------------------------

Converted file (box. obj. Flip ):

#
# Object box01
#

V-39.306316-32.828358 29.183971
V-39.306316 33.259296 29.183971
V 39.726025 33.259296 29.183971
V 39.726025-32.828358 29.183971
V-39.306316-32.828358-26.914204
V 39.726025-32.828358-26.914204
V 39.726025 33.259296-26.914204
V-39.306316 33.259296-26.914204

Code implementation:

 

 1 #include <fstream.h> 2 #include <math.h> 3  4 bool work(const char* path) 5 { 6     char chs[1000]; 7     double x,y,z; 8     CString newPath(path); 9     newPath += ".flip";10     const char* chNewPath = newPath;11     ofstream opf(chNewPath);12     if (!opf.is_open()) return false;13     ifstream pf(path);14     if (!pf.is_open()) {opf.close();return false;}15 16     while (!pf.eof())17     {18         pf.getline(chs, 1000, '\n');19         if (sscanf(chs, "v %lf %lf %lf", &x, &y, &z)==3)20         {21             CString strChs(chs);22             int spacePos=strChs.ReverseFind(' ');23             char c=strChs.GetAt(spacePos+1);24 25             opf<<(LPCTSTR)(strChs.Left(spacePos+1));26             if (c=='-')27             {28                 opf<<(LPCTSTR)(strChs.Right(strChs.GetLength()-spacePos-2))<<endl;29             }30             else31             {32                 if (fabs(z)>1e-6) opf<<"-";33                 opf<<(LPCTSTR)(strChs.Right(strChs.GetLength()-spacePos-1))<<endl;34             }35         }36         else37         {38             opf << chs << endl;39         }40     }41 42     opf.close();43     pf.close();44     return true;45 }