Original Post
I created an openGL program, and want to update texture several times on the same surface when needed. So, first, I init openGL program and created one texture object and binded it,then loaded a bmp file and map on the surface, these all worked well. Later, I loaded another bmp file and tried to map it on the surface using the same texture object , but failed, the texture on the surface didn't change. I don't know why. Please help, I just a beginner. the code of load texture() function: //////////////////////////////////////////////////////////////////// bool LoadTexture(LPTSTR szFileName, GLuint &texid) // Creates Texture From A Bitmap File { HBITMAP hBMP; // Handle Of The Bitmap BITMAP BMP; // Bitmap Structure //glGenTextures(1, &texid); // Create The Texture hBMP=(HBITMAP)LoadImage(GetModuleHandle(NULL), szFileName, IMAGE_BITMAP, 0, 0, LR_CREATEDIBSECTION | LR_LOADFROMFILE ); if (!hBMP) // Does The Bitmap Exist? return FALSE; // If Not Return False GetObject(hBMP, sizeof(BMP), &BMP); // Get The Object // hBMP: Handle To Graphics Object // sizeof(BMP): Size Of Buffer For Object Information // &BMP: Buffer For Object Information //glPixelStorei(GL_UNPACK_ALIGNMENT, 4); // Pixel Storage Mode (Word Alignment / 4 Bytes) // Typical Texture Generation Using Data From The Bitmap glBindTexture(GL_TEXTURE_2D, texid); // Bind To The Texture ID glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR); // Linear Min Filter glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR); // Linear Mag Filter glTexImage2D(GL_TEXTURE_2D, 0, 3, BMP.bmWidth, BMP.bmHeight, 0, GL_BGR_EXT, GL_UNSIGNED_BYTE, BMP.bmBits); DeleteObject(hBMP); // Delete The Object return TRUE; // Loading Was Successful } ////////////////////////////////////////////////////////////////////////