From 601c6e763cdde8a3c0d9765175ce20ddfd6f646d Mon Sep 17 00:00:00 2001
From: linesight <ted.lin0000@gmail.com>
Date: Mon, 27 Oct 2025 21:30:27 -0700
Subject: [PATCH] fix const cy::TriMesh::Str to const char * conversion

---
 cyTriMesh.h | 356 ++++++++++++++++++++++++++--------------------------
 1 file changed, 178 insertions(+), 178 deletions(-)

diff --git a/cyTriMesh.h b/cyTriMesh.h
index db92ea4..bd9194c 100644
--- a/cyTriMesh.h
+++ b/cyTriMesh.h
@@ -66,7 +66,7 @@ class TriMesh
 		Str() : data(nullptr) {}							//!< Constructor
 		Str( Str const &s ) : data(nullptr) { *this = s; }	//!< Copy constructor
 		~Str() { if ( data ) delete [] data; }				//!< Destructor
-		operator char const * () { return data; }			//!< Implicit conversion to const char
+		operator char const * () const { return data; }			//!< Implicit conversion to const char
 		void operator = ( Str  const &s ) { *this = s.data; }	//!< Assignment operator
 		void operator = ( char const *s ) { if (s) { size_t n=strlen(s); if (data) delete [] data; data=new char[n+1]; strncpy(data,s,n); data[n]='\0'; } else if (data) { delete [] data; data=nullptr; } }	//!< Assignment operator
 	};
@@ -192,14 +192,14 @@ class TriMesh
 	static Vec3f Interpolate( int i, Vec3f const *v, TriFace const *f, Vec3f const &bc ) { return v[f[i].v[0]]*bc.x + v[f[i].v[1]]*bc.y + v[f[i].v[2]]*bc.z; }
 
 	// Temporary structures
-	struct MtlData
-	{
-		std::string mtlName;
-		unsigned int firstFace;
-		unsigned int faceCount;
-		MtlData() { faceCount=0; firstFace=0; }
-	};
-	struct MtlLibName { std::string filename; };
+	struct MtlData
+	{
+		std::string mtlName;
+		unsigned int firstFace;
+		unsigned int faceCount;
+		MtlData() { faceCount=0; firstFace=0; }
+	};
+	struct MtlLibName { std::string filename; };
 };
 
 //-------------------------------------------------------------------------------
@@ -269,15 +269,15 @@ inline bool TriMesh::LoadFromFileObj( char const *filename, bool loadMtl, std::o
 		return false;
 	}
 
-	Clear();
-
-	class Buffer
-	{
-		char data[1024];
-		int readLine;
-	public:
-		int ReadLine(FILE *fp)
-		{
+	Clear();
+
+	class Buffer
+	{
+		char data[1024];
+		int readLine;
+	public:
+		int ReadLine(FILE *fp)
+		{
 			int c = fgetc(fp);
 			while ( !feof(fp) ) {
 				while ( isspace(c) && ( !feof(fp) || c!='\0' ) ) c = fgetc(fp);	// skip empty space
@@ -299,53 +299,53 @@ inline bool TriMesh::LoadFromFileObj( char const *filename, bool loadMtl, std::o
 			}
 			data[i] = '\0';
 			readLine = i;
-			return i;
-		}
-		char& operator[](int i) { return data[i]; }
-		void ReadVertex( Vec3f &v ) const { v.Zero(); sscanf( data+2, "%f %f %f", &v.x, &v.y, &v.z ); }
-		void ReadFloat3( float f[3] ) const { f[2]=f[1]=f[0]=0; int n = sscanf( data+2, "%f %f %f", &f[0], &f[1], &f[2] ); if ( n==1 ) f[2]=f[1]=f[0]; }
-		void ReadFloat( float *f ) const { sscanf( data+2, "%f", f ); }
-		void ReadInt( int *i, int start ) const { sscanf( data+start, "%d", i ); }
-		bool IsCommand( char const *cmd ) const {
-			int i=0;
-			while ( cmd[i]!='\0' ) {
-				if ( cmd[i] != data[i] ) return false;
-				i++;
-			}
-			return (data[i]=='\0' || data[i]==' ');
-		}
-		char const * Data(int start=0) { return data+start; }
-		void Copy( Str &str, int start=0 )
-		{
-			while ( data[start] != '\0' && data[start] <= ' ' ) start++;
-			str = Data(start);
-		}
-	};
-	Buffer buffer;
-
-
-	struct MtlList {
-		std::vector<MtlData> mtlData;
-		int GetMtlIndex( char const *mtlName )
-		{
-			for ( unsigned int i=0; i<mtlData.size(); i++ ) {
-				if ( mtlData[i].mtlName == mtlName ) return (int)i;
-			}
-			return -1;
-		}
-		int CreateMtl( char const *mtlName, unsigned int firstFace )
-		{
-			if ( mtlName[0] == '\0' ) return 0;
-			int i = GetMtlIndex(mtlName);
-			if ( i >= 0 ) return i;
-			MtlData m;
-			m.mtlName = mtlName;
-			m.firstFace = firstFace;
-			mtlData.push_back(m);
-			return (int)mtlData.size()-1;
-		}
-	};
-	MtlList mtlList;
+			return i;
+		}
+		char& operator[](int i) { return data[i]; }
+		void ReadVertex( Vec3f &v ) const { v.Zero(); sscanf( data+2, "%f %f %f", &v.x, &v.y, &v.z ); }
+		void ReadFloat3( float f[3] ) const { f[2]=f[1]=f[0]=0; int n = sscanf( data+2, "%f %f %f", &f[0], &f[1], &f[2] ); if ( n==1 ) f[2]=f[1]=f[0]; }
+		void ReadFloat( float *f ) const { sscanf( data+2, "%f", f ); }
+		void ReadInt( int *i, int start ) const { sscanf( data+start, "%d", i ); }
+		bool IsCommand( char const *cmd ) const {
+			int i=0;
+			while ( cmd[i]!='\0' ) {
+				if ( cmd[i] != data[i] ) return false;
+				i++;
+			}
+			return (data[i]=='\0' || data[i]==' ');
+		}
+		char const * Data(int start=0) { return data+start; }
+		void Copy( Str &str, int start=0 )
+		{
+			while ( data[start] != '\0' && data[start] <= ' ' ) start++;
+			str = Data(start);
+		}
+	};
+	Buffer buffer;
+
+
+	struct MtlList {
+		std::vector<MtlData> mtlData;
+		int GetMtlIndex( char const *mtlName )
+		{
+			for ( unsigned int i=0; i<mtlData.size(); i++ ) {
+				if ( mtlData[i].mtlName == mtlName ) return (int)i;
+			}
+			return -1;
+		}
+		int CreateMtl( char const *mtlName, unsigned int firstFace )
+		{
+			if ( mtlName[0] == '\0' ) return 0;
+			int i = GetMtlIndex(mtlName);
+			if ( i >= 0 ) return i;
+			MtlData m;
+			m.mtlName = mtlName;
+			m.firstFace = firstFace;
+			mtlData.push_back(m);
+			return (int)mtlData.size()-1;
+		}
+	};
+	MtlList mtlList;
 
 	std::vector<Vec3f>      _v;		// vertices
 	std::vector<TriFace>    _f;		// faces
@@ -353,12 +353,12 @@ inline bool TriMesh::LoadFromFileObj( char const *filename, bool loadMtl, std::o
 	std::vector<TriFace>    _fn;	// normal faces
 	std::vector<Vec3f>      _vt;	// texture vertices
 	std::vector<TriFace>    _ft;	// texture faces
-	std::vector<MtlLibName> mtlFiles;
-	std::vector<int>        faceMtlIndex;
-
-	int currentMtlIndex = -1;
-	bool hasTextures=false, hasNormals=false;
-
+	std::vector<MtlLibName> mtlFiles;
+	std::vector<int>        faceMtlIndex;
+
+	int currentMtlIndex = -1;
+	bool hasTextures=false, hasNormals=false;
+
 	while ( int rb = buffer.ReadLine(fp) ) {
 		if ( buffer.IsCommand("v") ) {
 			Vec3f vertex;
@@ -378,65 +378,65 @@ inline bool TriMesh::LoadFromFileObj( char const *filename, bool loadMtl, std::o
 			hasNormals = true;
 		}
 		else if ( buffer.IsCommand("f") ) {
-			int facevert = -1;
-			bool inspace = true;
-			bool negative = false;
-			int type = 0;
-			unsigned int index;
-			TriFace face, textureFace, normalFace;
-			unsigned int nFacesBefore = (unsigned int)_f.size();
-			for ( int i=2; i<rb; i++ ) {
-				if ( buffer[i] == ' ' ) inspace = true;
-				else {
-					if ( inspace ) {
-						inspace=false;
-						negative = false;
-						type=0;
-						index=0;
-						switch ( facevert ) {
-							case -1:
-								// initialize face
-								face.v[0] = face.v[1] = face.v[2] = 0;
-								textureFace.v[0] = textureFace.v[1] = textureFace.v[2] = 0;
-								normalFace. v[0] = normalFace. v[1] = normalFace. v[2] = 0;
-							case 0:
-							case 1:
-								facevert++;
-								break;
-							case 2:
-								// copy the first two vertices from the previous face
-								_f.push_back(face);
-								face.v[1] = face.v[2];
-								if ( hasTextures ) {
-									_ft.push_back(textureFace);
-									textureFace.v[1] = textureFace.v[2];
-								}
-								if ( hasNormals ) {
-									_fn.push_back(normalFace);
-									normalFace.v[1] = normalFace.v[2];
-								}
-								faceMtlIndex.push_back(currentMtlIndex);
-								break;
-						}
-					}
-					if ( buffer[i] == '/' ) { type++; index=0; }
-					if ( buffer[i] == '-' ) negative = true;
-					if ( buffer[i] >= '0' && buffer[i] <= '9' ) {
-						index = index*10 + (buffer[i]-'0');
-						switch ( type ) {
-							case 0: face.v       [facevert] = negative ? (unsigned int)_v. size()-index : index-1; break;
-							case 1: textureFace.v[facevert] = negative ? (unsigned int)_vt.size()-index : index-1; hasTextures=true; break;
-							case 2: normalFace.v [facevert] = negative ? (unsigned int)_vn.size()-index : index-1; hasNormals =true; break;
-						}
-					}
-				}
-			}
-			_f.push_back(face);
-			if ( hasTextures ) _ft.push_back(textureFace);
-			if ( hasNormals  ) _fn.push_back(normalFace);
-			faceMtlIndex.push_back(currentMtlIndex);
-			if ( currentMtlIndex>=0 ) mtlList.mtlData[currentMtlIndex].faceCount += (unsigned int)_f.size() - nFacesBefore;
-		}
+			int facevert = -1;
+			bool inspace = true;
+			bool negative = false;
+			int type = 0;
+			unsigned int index;
+			TriFace face, textureFace, normalFace;
+			unsigned int nFacesBefore = (unsigned int)_f.size();
+			for ( int i=2; i<rb; i++ ) {
+				if ( buffer[i] == ' ' ) inspace = true;
+				else {
+					if ( inspace ) {
+						inspace=false;
+						negative = false;
+						type=0;
+						index=0;
+						switch ( facevert ) {
+							case -1:
+								// initialize face
+								face.v[0] = face.v[1] = face.v[2] = 0;
+								textureFace.v[0] = textureFace.v[1] = textureFace.v[2] = 0;
+								normalFace. v[0] = normalFace. v[1] = normalFace. v[2] = 0;
+							case 0:
+							case 1:
+								facevert++;
+								break;
+							case 2:
+								// copy the first two vertices from the previous face
+								_f.push_back(face);
+								face.v[1] = face.v[2];
+								if ( hasTextures ) {
+									_ft.push_back(textureFace);
+									textureFace.v[1] = textureFace.v[2];
+								}
+								if ( hasNormals ) {
+									_fn.push_back(normalFace);
+									normalFace.v[1] = normalFace.v[2];
+								}
+								faceMtlIndex.push_back(currentMtlIndex);
+								break;
+						}
+					}
+					if ( buffer[i] == '/' ) { type++; index=0; }
+					if ( buffer[i] == '-' ) negative = true;
+					if ( buffer[i] >= '0' && buffer[i] <= '9' ) {
+						index = index*10 + (buffer[i]-'0');
+						switch ( type ) {
+							case 0: face.v       [facevert] = negative ? (unsigned int)_v. size()-index : index-1; break;
+							case 1: textureFace.v[facevert] = negative ? (unsigned int)_vt.size()-index : index-1; hasTextures=true; break;
+							case 2: normalFace.v [facevert] = negative ? (unsigned int)_vn.size()-index : index-1; hasNormals =true; break;
+						}
+					}
+				}
+			}
+			_f.push_back(face);
+			if ( hasTextures ) _ft.push_back(textureFace);
+			if ( hasNormals  ) _fn.push_back(normalFace);
+			faceMtlIndex.push_back(currentMtlIndex);
+			if ( currentMtlIndex>=0 ) mtlList.mtlData[currentMtlIndex].faceCount += (unsigned int)_f.size() - nFacesBefore;
+		}
 		else if ( loadMtl ) {
 			if ( buffer.IsCommand("usemtl") ) {
 				currentMtlIndex = mtlList.CreateMtl(buffer.Data(7), (unsigned int)_f.size());
@@ -447,55 +447,55 @@ inline bool TriMesh::LoadFromFileObj( char const *filename, bool loadMtl, std::o
 				mtlFiles.push_back(libName);
 			}
 		}
-		if ( feof(fp) ) break;
-	}
-
+		if ( feof(fp) ) break;
+	}
+
 	fclose(fp);
-
-
-	if ( _f.size() == 0 ) return true; // No faces found
-	SetNumVertex((unsigned int)_v.size());
-	SetNumFaces((unsigned int)_f.size());
-	SetNumTexVerts((unsigned int)_vt.size());
-	SetNumNormals((unsigned int)_vn.size());
-	if ( loadMtl ) SetNumMtls((unsigned int)mtlList.mtlData.size());
-
-	// Copy data
-	memcpy(v, _v.data(), sizeof(Vec3f)*_v.size());
-	if ( _vt.size() > 0 ) memcpy(vt, _vt.data(), sizeof(Vec3f)*_vt.size());
-	if ( _vn.size() > 0 ) memcpy(vn, _vn.data(), sizeof(Vec3f)*_vn.size());
-
-	if ( mtlList.mtlData.size() > 0 ) {
-		unsigned int fid = 0;
-		for ( int mi=0; mi<(int)mtlList.mtlData.size(); mi++ ) {
-			for ( unsigned int i=mtlList.mtlData[mi].firstFace, j=0; j<mtlList.mtlData[mi].faceCount && i<_f.size(); i++ ) {
-				if ( faceMtlIndex[i] == mi ) {
-					f[fid] = _f[i];
-					if ( fn ) fn[fid] = _fn[i];
-					if ( ft ) ft[fid] = _ft[i];
-					fid++;
-					j++;
-				}
-			}
-			mcfc[mi] = fid;
-		}
-		if ( fid <_f.size() ) {
-			for ( unsigned int i=0; i<_f.size(); i++ ) {
-				if ( faceMtlIndex[i] < 0 ) {
-					f[fid] = _f[i];
-					if ( fn ) fn[fid] = _fn[i];
-					if ( ft ) ft[fid] = _ft[i];
-					fid++;
-				}
-			}
-		}
-	} else {
-		memcpy(f, _f.data(), sizeof(TriFace)*_f.size());
-		if ( ft ) memcpy(ft, _ft.data(), sizeof(TriFace)*_ft.size());
-		if ( fn ) memcpy(fn, _fn.data(), sizeof(TriFace)*_fn.size());
-	}
-
-
+
+
+	if ( _f.size() == 0 ) return true; // No faces found
+	SetNumVertex((unsigned int)_v.size());
+	SetNumFaces((unsigned int)_f.size());
+	SetNumTexVerts((unsigned int)_vt.size());
+	SetNumNormals((unsigned int)_vn.size());
+	if ( loadMtl ) SetNumMtls((unsigned int)mtlList.mtlData.size());
+
+	// Copy data
+	memcpy(v, _v.data(), sizeof(Vec3f)*_v.size());
+	if ( _vt.size() > 0 ) memcpy(vt, _vt.data(), sizeof(Vec3f)*_vt.size());
+	if ( _vn.size() > 0 ) memcpy(vn, _vn.data(), sizeof(Vec3f)*_vn.size());
+
+	if ( mtlList.mtlData.size() > 0 ) {
+		unsigned int fid = 0;
+		for ( int mi=0; mi<(int)mtlList.mtlData.size(); mi++ ) {
+			for ( unsigned int i=mtlList.mtlData[mi].firstFace, j=0; j<mtlList.mtlData[mi].faceCount && i<_f.size(); i++ ) {
+				if ( faceMtlIndex[i] == mi ) {
+					f[fid] = _f[i];
+					if ( fn ) fn[fid] = _fn[i];
+					if ( ft ) ft[fid] = _ft[i];
+					fid++;
+					j++;
+				}
+			}
+			mcfc[mi] = fid;
+		}
+		if ( fid <_f.size() ) {
+			for ( unsigned int i=0; i<_f.size(); i++ ) {
+				if ( faceMtlIndex[i] < 0 ) {
+					f[fid] = _f[i];
+					if ( fn ) fn[fid] = _fn[i];
+					if ( ft ) ft[fid] = _ft[i];
+					fid++;
+				}
+			}
+		}
+	} else {
+		memcpy(f, _f.data(), sizeof(TriFace)*_f.size());
+		if ( ft ) memcpy(ft, _ft.data(), sizeof(TriFace)*_ft.size());
+		if ( fn ) memcpy(fn, _fn.data(), sizeof(TriFace)*_fn.size());
+	}
+
+
 	// Load the .mtl files
 	if ( loadMtl ) {
 		// get the path from filename