SOIL库加载纹理

NeHe教程里第六课使用glaux来加载纹理位图，但是glaux 库已经弃用。新的NeHe第六课教程中推荐了SOIL库。（下载，可以在这里获取能直接使用的文件）

SOIL库是一个小型的C语言库，用来加载纹理到OpenGL。它基于stb_image 1.16。
详情：http://www.lonesock.net/soil.html
我们使用时只需要简单的把SOIL.h SOIL.lib添加到工程就可以了。

bmp文件的使用：
在InitGL()中调用LoadGlTextures()函数：

int LoadGLTextures()                                    // Load Bitmaps And Convert To Textures  
{  /* load an image file directly as a new OpenGL texture */  texture[0] = SOIL_load_OGL_texture  (  "Data/NeHe.bmp",  SOIL_LOAD_AUTO,  SOIL_CREATE_NEW_ID,  SOIL_FLAG_INVERT_Y  );  if(texture[0] == 0)  return false;  // Typical Texture Generation Using Data From The Bitmap  glBindTexture(GL_TEXTURE_2D, texture[0]);  glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_LINEAR);  glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_LINEAR);  return true;                                        // Return Success  
}  

unsigned int SOIL_load_OGL_texture(
const char *filename,
int force_channels,
unsigned int reuse_texture_ID,
unsigned int flags);
第一个参数为文件名；
第二个说明符，SOIL_LOAD_AUTO表示使用我们磁盘载入的；
第三个表示让SOIL为我们创建一个ID；
第四个参数SOIL_FLAG_INVERT_Y允许我们做是翻转Y轴
返回值，0表示失败，其他表示OpenGL上下文句柄

效果：

实例：

/**      This Code Was Created By Jeff Molofee 2000*      A HUGE Thanks To Fredric Echols For Cleaning Up*      And Optimizing The Base Code, Making It More Flexible!*      If You've Found This Code Useful, Please Let Me Know.*      Visit My Site At nehe.gamedev.net*/#include <windows.h>        // Header File For Windows
#include <stdio.h>          // Header File For Standard Input/Output
#include <gl\gl.h>          // Header File For The OpenGL32 Library
#include <gl\glu.h>         // Header File For The GLu32 Library#include "SOIL.h"HDC         hDC=NULL;       // Private GDI Device Context
HGLRC       hRC=NULL;       // Permanent Rendering Context
HWND        hWnd=NULL;      // Holds Our Window Handle
HINSTANCE   hInstance;      // Holds The Instance Of The Applicationbool    keys[256];          // Array Used For The Keyboard Routine
bool    active=TRUE;        // Window Active Flag Set To TRUE By Default
bool    fullscreen=TRUE;    // Fullscreen Flag Set To Fullscreen Mode By DefaultGLfloat xrot;               // X Rotation ( NEW )
GLfloat yrot;               // Y Rotation ( NEW )
GLfloat zrot;               // Z Rotation ( NEW )GLuint  texture[1];         // Storage For One Texture ( NEW )LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);   // Declaration For WndProcint LoadGLTextures()                                    // Load Bitmaps And Convert To Textures
{/* load an image file directly as a new OpenGL texture */texture[0] = SOIL_load_OGL_texture("Data/NeHe.bmp",SOIL_LOAD_AUTO,SOIL_CREATE_NEW_ID,SOIL_FLAG_INVERT_Y);if(texture[0] == 0)return false;// Typical Texture Generation Using Data From The BitmapglBindTexture(GL_TEXTURE_2D, texture[0]);glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_LINEAR);glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_LINEAR);return true;                                        // Return Success
}GLvoid ReSizeGLScene(GLsizei width, GLsizei height)     // Resize And Initialize The GL Window
{if (height==0)                                      // Prevent A Divide By Zero By{height=1;                                       // Making Height Equal One}glViewport(0,0,width,height);                       // Reset The Current ViewportglMatrixMode(GL_PROJECTION);                        // Select The Projection MatrixglLoadIdentity();                                   // Reset The Projection Matrix// Calculate The Aspect Ratio Of The WindowgluPerspective(45.0f,(GLfloat)width/(GLfloat)height,0.1f,100.0f);glMatrixMode(GL_MODELVIEW);                         // Select The Modelview MatrixglLoadIdentity();                                   // Reset The Modelview Matrix
}int InitGL(GLvoid)                                      // All Setup For OpenGL Goes Here
{if (!LoadGLTextures())                              // Jump To Texture Loading Routine ( NEW ){return FALSE;                                   // If Texture Didn't Load Return FALSE}glEnable(GL_TEXTURE_2D);                            // Enable Texture Mapping ( NEW )glShadeModel(GL_SMOOTH);                            // Enable Smooth ShadingglClearColor(0.0f, 0.0f, 0.0f, 0.5f);               // Black BackgroundglClearDepth(1.0f);                                 // Depth Buffer SetupglEnable(GL_DEPTH_TEST);                            // Enables Depth TestingglDepthFunc(GL_LEQUAL);                             // The Type Of Depth Testing To DoglHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST);  // Really Nice Perspective Calculationsreturn TRUE;                                        // Initialization Went OK
}int DrawGLScene(GLvoid)                                 // Here's Where We Do All The Drawing
{glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); // Clear The Screen And The Depth BufferglLoadIdentity();                                   // Reset The ViewglTranslatef(0.0f,0.0f,-5.0f);glRotatef(xrot,1.0f,0.0f,0.0f);glRotatef(yrot,0.0f,1.0f,0.0f);glRotatef(zrot,0.0f,0.0f,1.0f);glBindTexture(GL_TEXTURE_2D, texture[0]);glBegin(GL_QUADS);// Front FaceglTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f, -1.0f,  1.0f);glTexCoord2f(1.0f, 0.0f); glVertex3f( 1.0f, -1.0f,  1.0f);glTexCoord2f(1.0f, 1.0f); glVertex3f( 1.0f,  1.0f,  1.0f);glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f,  1.0f,  1.0f);// Back FaceglTexCoord2f(1.0f, 0.0f); glVertex3f(-1.0f, -1.0f, -1.0f);glTexCoord2f(1.0f, 1.0f); glVertex3f(-1.0f,  1.0f, -1.0f);glTexCoord2f(0.0f, 1.0f); glVertex3f( 1.0f,  1.0f, -1.0f);glTexCoord2f(0.0f, 0.0f); glVertex3f( 1.0f, -1.0f, -1.0f);// Top FaceglTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f,  1.0f, -1.0f);glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f,  1.0f,  1.0f);glTexCoord2f(1.0f, 0.0f); glVertex3f( 1.0f,  1.0f,  1.0f);glTexCoord2f(1.0f, 1.0f); glVertex3f( 1.0f,  1.0f, -1.0f);// Bottom FaceglTexCoord2f(1.0f, 1.0f); glVertex3f(-1.0f, -1.0f, -1.0f);glTexCoord2f(0.0f, 1.0f); glVertex3f( 1.0f, -1.0f, -1.0f);glTexCoord2f(0.0f, 0.0f); glVertex3f( 1.0f, -1.0f,  1.0f);glTexCoord2f(1.0f, 0.0f); glVertex3f(-1.0f, -1.0f,  1.0f);// Right faceglTexCoord2f(1.0f, 0.0f); glVertex3f( 1.0f, -1.0f, -1.0f);glTexCoord2f(1.0f, 1.0f); glVertex3f( 1.0f,  1.0f, -1.0f);glTexCoord2f(0.0f, 1.0f); glVertex3f( 1.0f,  1.0f,  1.0f);glTexCoord2f(0.0f, 0.0f); glVertex3f( 1.0f, -1.0f,  1.0f);// Left FaceglTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f, -1.0f, -1.0f);glTexCoord2f(1.0f, 0.0f); glVertex3f(-1.0f, -1.0f,  1.0f);glTexCoord2f(1.0f, 1.0f); glVertex3f(-1.0f,  1.0f,  1.0f);glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f,  1.0f, -1.0f);glEnd();xrot+=0.3f;yrot+=0.2f;zrot+=0.4f;return TRUE;                                        // Keep Going
}GLvoid KillGLWindow(GLvoid)                             // Properly Kill The Window
{if (fullscreen)                                     // Are We In Fullscreen Mode?{ChangeDisplaySettings(NULL,0);                  // If So Switch Back To The DesktopShowCursor(TRUE);                               // Show Mouse Pointer}if (hRC)                                            // Do We Have A Rendering Context?{if (!wglMakeCurrent(NULL,NULL))                 // Are We Able To Release The DC And RC Contexts?{MessageBox(NULL,"Release Of DC And RC Failed.","SHUTDOWN ERROR",MB_OK | MB_ICONINFORMATION);}if (!wglDeleteContext(hRC))                     // Are We Able To Delete The RC?{MessageBox(NULL,"Release Rendering Context Failed.","SHUTDOWN ERROR",MB_OK | MB_ICONINFORMATION);}hRC=NULL;                                       // Set RC To NULL}if (hDC && !ReleaseDC(hWnd,hDC))                    // Are We Able To Release The DC{MessageBox(NULL,"Release Device Context Failed.","SHUTDOWN ERROR",MB_OK | MB_ICONINFORMATION);hDC=NULL;                                       // Set DC To NULL}if (hWnd && !DestroyWindow(hWnd))                   // Are We Able To Destroy The Window?{MessageBox(NULL,"Could Not Release hWnd.","SHUTDOWN ERROR",MB_OK | MB_ICONINFORMATION);hWnd=NULL;                                      // Set hWnd To NULL}if (!UnregisterClass("OpenGL",hInstance))           // Are We Able To Unregister Class{MessageBox(NULL,"Could Not Unregister Class.","SHUTDOWN ERROR",MB_OK | MB_ICONINFORMATION);hInstance=NULL;                                 // Set hInstance To NULL}
}/*  This Code Creates Our OpenGL Window.  Parameters Are:                   **  title           - Title To Appear At The Top Of The Window              **  width           - Width Of The GL Window Or Fullscreen Mode             **  height          - Height Of The GL Window Or Fullscreen Mode            **  bits            - Number Of Bits To Use For Color (8/16/24/32)          **  fullscreenflag  - Use Fullscreen Mode (TRUE) Or Windowed Mode (FALSE)   */BOOL CreateGLWindow(char* title, int width, int height, int bits, bool fullscreenflag)
{GLuint      PixelFormat;            // Holds The Results After Searching For A MatchWNDCLASS    wc;                     // Windows Class StructureDWORD       dwExStyle;              // Window Extended StyleDWORD       dwStyle;                // Window StyleRECT        WindowRect;             // Grabs Rectangle Upper Left / Lower Right ValuesWindowRect.left=(long)0;            // Set Left Value To 0WindowRect.right=(long)width;       // Set Right Value To Requested WidthWindowRect.top=(long)0;             // Set Top Value To 0WindowRect.bottom=(long)height;     // Set Bottom Value To Requested Heightfullscreen=fullscreenflag;          // Set The Global Fullscreen FlaghInstance           = GetModuleHandle(NULL);                // Grab An Instance For Our Windowwc.style            = CS_HREDRAW | CS_VREDRAW | CS_OWNDC;   // Redraw On Size, And Own DC For Window.wc.lpfnWndProc      = (WNDPROC) WndProc;                    // WndProc Handles Messageswc.cbClsExtra       = 0;                                    // No Extra Window Datawc.cbWndExtra       = 0;                                    // No Extra Window Datawc.hInstance        = hInstance;                            // Set The Instancewc.hIcon            = LoadIcon(NULL, IDI_WINLOGO);          // Load The Default Iconwc.hCursor          = LoadCursor(NULL, IDC_ARROW);          // Load The Arrow Pointerwc.hbrBackground    = NULL;                                 // No Background Required For GLwc.lpszMenuName     = NULL;                                 // We Don't Want A Menuwc.lpszClassName    = "OpenGL";                             // Set The Class Nameif (!RegisterClass(&wc))                                    // Attempt To Register The Window Class{MessageBox(NULL,"Failed To Register The Window Class.","ERROR",MB_OK|MB_ICONEXCLAMATION);return FALSE;                                           // Return FALSE}if (fullscreen)                                             // Attempt Fullscreen Mode?{DEVMODE dmScreenSettings;                               // Device Modememset(&dmScreenSettings,0,sizeof(dmScreenSettings));   // Makes Sure Memory's CleareddmScreenSettings.dmSize=sizeof(dmScreenSettings);       // Size Of The Devmode StructuredmScreenSettings.dmPelsWidth    = width;                // Selected Screen WidthdmScreenSettings.dmPelsHeight   = height;               // Selected Screen HeightdmScreenSettings.dmBitsPerPel   = bits;                 // Selected Bits Per PixeldmScreenSettings.dmFields=DM_BITSPERPEL|DM_PELSWIDTH|DM_PELSHEIGHT;// Try To Set Selected Mode And Get Results.  NOTE: CDS_FULLSCREEN Gets Rid Of Start Bar.if (ChangeDisplaySettings(&dmScreenSettings,CDS_FULLSCREEN)!=DISP_CHANGE_SUCCESSFUL){// If The Mode Fails, Offer Two Options.  Quit Or Use Windowed Mode.if (MessageBox(NULL,"The Requested Fullscreen Mode Is Not Supported By\nYour Video Card. Use Windowed Mode Instead?","NeHe GL",MB_YESNO|MB_ICONEXCLAMATION)==IDYES){fullscreen=FALSE;       // Windowed Mode Selected.  Fullscreen = FALSE}else{// Pop Up A Message Box Letting User Know The Program Is Closing.MessageBox(NULL,"Program Will Now Close.","ERROR",MB_OK|MB_ICONSTOP);return FALSE;                                   // Return FALSE}}}if (fullscreen)                                             // Are We Still In Fullscreen Mode?{dwExStyle=WS_EX_APPWINDOW;                              // Window Extended StyledwStyle=WS_POPUP;                                       // Windows StyleShowCursor(FALSE);                                      // Hide Mouse Pointer}else{dwExStyle=WS_EX_APPWINDOW | WS_EX_WINDOWEDGE;           // Window Extended StyledwStyle=WS_OVERLAPPEDWINDOW;                            // Windows Style}AdjustWindowRectEx(&WindowRect, dwStyle, FALSE, dwExStyle);     // Adjust Window To True Requested Size// Create The Windowif (!(hWnd=CreateWindowEx(  dwExStyle,                          // Extended Style For The Window"OpenGL",                           // Class Nametitle,                              // Window TitledwStyle |                           // Defined Window StyleWS_CLIPSIBLINGS |                   // Required Window StyleWS_CLIPCHILDREN,                    // Required Window Style0, 0,                               // Window PositionWindowRect.right-WindowRect.left,   // Calculate Window WidthWindowRect.bottom-WindowRect.top,   // Calculate Window HeightNULL,                               // No Parent WindowNULL,                               // No MenuhInstance,                          // InstanceNULL)))                             // Dont Pass Anything To WM_CREATE{KillGLWindow();                             // Reset The DisplayMessageBox(NULL,"Window Creation Error.","ERROR",MB_OK|MB_ICONEXCLAMATION);return FALSE;                               // Return FALSE}static  PIXELFORMATDESCRIPTOR pfd=              // pfd Tells Windows How We Want Things To Be{sizeof(PIXELFORMATDESCRIPTOR),              // Size Of This Pixel Format Descriptor1,                                          // Version NumberPFD_DRAW_TO_WINDOW |                        // Format Must Support WindowPFD_SUPPORT_OPENGL |                        // Format Must Support OpenGLPFD_DOUBLEBUFFER,                           // Must Support Double BufferingPFD_TYPE_RGBA,                              // Request An RGBA Formatbits,                                       // Select Our Color Depth0, 0, 0, 0, 0, 0,                           // Color Bits Ignored0,                                          // No Alpha Buffer0,                                          // Shift Bit Ignored0,                                          // No Accumulation Buffer0, 0, 0, 0,                                 // Accumulation Bits Ignored16,                                         // 16Bit Z-Buffer (Depth Buffer)  0,                                          // No Stencil Buffer0,                                          // No Auxiliary BufferPFD_MAIN_PLANE,                             // Main Drawing Layer0,                                          // Reserved0, 0, 0                                     // Layer Masks Ignored};if (!(hDC=GetDC(hWnd)))                         // Did We Get A Device Context?{KillGLWindow();                             // Reset The DisplayMessageBox(NULL,"Can't Create A GL Device Context.","ERROR",MB_OK|MB_ICONEXCLAMATION);return FALSE;                               // Return FALSE}if (!(PixelFormat=ChoosePixelFormat(hDC,&pfd))) // Did Windows Find A Matching Pixel Format?{KillGLWindow();                             // Reset The DisplayMessageBox(NULL,"Can't Find A Suitable PixelFormat.","ERROR",MB_OK|MB_ICONEXCLAMATION);return FALSE;                               // Return FALSE}if(!SetPixelFormat(hDC,PixelFormat,&pfd))       // Are We Able To Set The Pixel Format?{KillGLWindow();                             // Reset The DisplayMessageBox(NULL,"Can't Set The PixelFormat.","ERROR",MB_OK|MB_ICONEXCLAMATION);return FALSE;                               // Return FALSE}if (!(hRC=wglCreateContext(hDC)))               // Are We Able To Get A Rendering Context?{KillGLWindow();                             // Reset The DisplayMessageBox(NULL,"Can't Create A GL Rendering Context.","ERROR",MB_OK|MB_ICONEXCLAMATION);return FALSE;                               // Return FALSE}if(!wglMakeCurrent(hDC,hRC))                    // Try To Activate The Rendering Context{KillGLWindow();                             // Reset The DisplayMessageBox(NULL,"Can't Activate The GL Rendering Context.","ERROR",MB_OK|MB_ICONEXCLAMATION);return FALSE;                               // Return FALSE}ShowWindow(hWnd,SW_SHOW);                       // Show The WindowSetForegroundWindow(hWnd);                      // Slightly Higher PrioritySetFocus(hWnd);                                 // Sets Keyboard Focus To The WindowReSizeGLScene(width, height);                   // Set Up Our Perspective GL Screenif (!InitGL())                                  // Initialize Our Newly Created GL Window{KillGLWindow();                             // Reset The DisplayMessageBox(NULL,"Initialization Failed.","ERROR",MB_OK|MB_ICONEXCLAMATION);return FALSE;                               // Return FALSE}return TRUE;                                    // Success
}LRESULT CALLBACK WndProc(   HWND    hWnd,           // Handle For This WindowUINT    uMsg,           // Message For This WindowWPARAM  wParam,         // Additional Message InformationLPARAM  lParam)         // Additional Message Information
{switch (uMsg)                                   // Check For Windows Messages{case WM_ACTIVATE:                           // Watch For Window Activate Message{if (!HIWORD(wParam))                    // Check Minimization State{active=TRUE;                        // Program Is Active}else{active=FALSE;                       // Program Is No Longer Active}return 0;                               // Return To The Message Loop}case WM_SYSCOMMAND:                         // Intercept System Commands{switch (wParam)                         // Check System Calls{case SC_SCREENSAVE:                 // Screensaver Trying To Start?case SC_MONITORPOWER:               // Monitor Trying To Enter Powersave?return 0;                           // Prevent From Happening}break;                                  // Exit}case WM_CLOSE:                              // Did We Receive A Close Message?{PostQuitMessage(0);                     // Send A Quit Messagereturn 0;                               // Jump Back}case WM_KEYDOWN:                            // Is A Key Being Held Down?{keys[wParam] = TRUE;                    // If So, Mark It As TRUEreturn 0;                               // Jump Back}case WM_KEYUP:                              // Has A Key Been Released?{keys[wParam] = FALSE;                   // If So, Mark It As FALSEreturn 0;                               // Jump Back}case WM_SIZE:                               // Resize The OpenGL Window{ReSizeGLScene(LOWORD(lParam),HIWORD(lParam));  // LoWord=Width, HiWord=Heightreturn 0;                               // Jump Back}}// Pass All Unhandled Messages To DefWindowProcreturn DefWindowProc(hWnd,uMsg,wParam,lParam);
}int WINAPI WinMain( HINSTANCE   hInstance,          // InstanceHINSTANCE   hPrevInstance,      // Previous InstanceLPSTR       lpCmdLine,          // Command Line Parametersint         nCmdShow)           // Window Show State
{MSG     msg;                                    // Windows Message StructureBOOL    done=FALSE;                             // Bool Variable To Exit Loop// Ask The User Which Screen Mode They Preferif (MessageBox(NULL,"Would You Like To Run In Fullscreen Mode?", "Start FullScreen?",MB_YESNO|MB_ICONQUESTION)==IDNO){fullscreen=FALSE;                           // Windowed Mode}// Create Our OpenGL Windowif (!CreateGLWindow("NeHe's Texture Mapping Tutorial",640,480,16,fullscreen)){return 0;                                   // Quit If Window Was Not Created}while(!done)                                    // Loop That Runs While done=FALSE{if (PeekMessage(&msg,NULL,0,0,PM_REMOVE))   // Is There A Message Waiting?{if (msg.message==WM_QUIT)               // Have We Received A Quit Message?{done=TRUE;                          // If So done=TRUE}else                                    // If Not, Deal With Window Messages{TranslateMessage(&msg);             // Translate The MessageDispatchMessage(&msg);              // Dispatch The Message}}else                                        // If There Are No Messages{// Draw The Scene.  Watch For ESC Key And Quit Messages From DrawGLScene()if ((active && !DrawGLScene()) || keys[VK_ESCAPE])  // Active?  Was There A Quit Received?{done=TRUE;                          // ESC or DrawGLScene Signalled A Quit}else                                    // Not Time To Quit, Update Screen{SwapBuffers(hDC);                   // Swap Buffers (Double Buffering)}if (keys[VK_F1])                        // Is F1 Being Pressed?{keys[VK_F1]=FALSE;                  // If So Make Key FALSEKillGLWindow();                     // Kill Our Current Windowfullscreen=!fullscreen;             // Toggle Fullscreen / Windowed Mode// Recreate Our OpenGL Windowif (!CreateGLWindow("NeHe's Texture Mapping Tutorial",640,480,16,fullscreen)){return 0;                       // Quit If Window Was Not Created}}}}// ShutdownKillGLWindow();                                 // Kill The Windowreturn (msg.wParam);                            // Exit The Program
}