《高效學習OpenGL》之紋理對象glGenTextures（）,glIsTexture（

1、(),gIIsTexture(。？效學習OpenGL之紋理對象gIGenTextures命名紋理對象:cppviewplaincopyprint?匸voidglGenTextures(GLsizein,GLuint*textures);/在數(shù)組textures中返回n個當期未使？的值，表？紋理對象的名稱/零作為？個保留的紋理對象名，它不會被此函數(shù)當做紋理對象名稱？返回判斷？個紋理名稱是否處于實際使？中:cppviewplaincopyprint?JGLbooleanglIsTexture(GLuinttexture);/如果texture是？個已綁定的紋理對象名稱，并且沒有刪除，就返回GL_T

2、RUE；創(chuàng)建和使？紋理對象：cppviewplaincopyprint?匚glBindTexture(GL_TEXTURE_2D,texName0);voidglBindTexture(GLenumtarget,GLuinttexture);/應？程序第？次在這個函數(shù)使？texture值時，這個函數(shù)將會創(chuàng)建？個新的紋理對象/當texture是？個以前已經(jīng)創(chuàng)建的紋理對象時，這個紋理對象就成為活動對象/如果texture為0,就停？使？這個紋理對象，并返回？名稱的默認紋理清除紋理對象:cppviewplaincopyprint?匸glDeleteTextures(2,texName);voidgl

3、DeleteTextures(GLsizein,constGLuint*textures);/刪除n個紋理對象，它們的名稱由textures數(shù)組提供實例:cppviewplaincopyprint?#include#include#include4.#ifdefGL_VERSION_1_1/*Createcheckerboardtexture*/#definechecklmageWidth64#definecheckImageHeight64staticGLubytechecklmagechecklmageHeightchecklmageWidth4;staticGLubyteotherlma

4、gechecklmageHeightchecklmageWidth4;11.staticGLuinttexName2;13.voidmakeChecklmages(void)inti,j,c;17.for(i=0;icheckImageHeight;i+)19.20.21.22.23.24.25.26.27.28.29.30.31.32.33.34.35.36.37.38.39.40.41.42.43.44.45.46.47.48.49.50.51.52.53.54.55.56.57.58.59.60.61.62.63.64.65.66.67.68.69.70.71.72.73.74.for(

5、j=0;jchecklmageWidth;j+)c=(i&0 x8)=0)A(j&0 x8)=0)*255;checklmageij0=(GLubyte)c;checklmageij1=(GLubyte)c;checklmageij2=(GLubyte)c;checklmageij3=(GLubyte)255;c=(i&0 x10)=0)A(j&0 x10)=0)*255;otherlmageij0=(GLubyte)c;otherlmageij1=(GLubyte)0;otherlmageij2=(GLubyte)0;otherlmageij3=(GLubyte)255;voidinit(v

6、oid)glClearColor(0.0,0.0,0.0,0.0);glShadeModel(GL_FLAT);glEnable(GL_DEPTH_TEST);makeChecklmages();glPixelStorei(GL_UNPACK_ALIGNMENT,1);glGenTextures(2,texName);glBindTexture(GL_TEXTURE_2D,texName0);glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_WRAP_S,GL_CLAMP);glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_WRA

7、P_T,GL_CLAMP);glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FlLTER,GL_NEAREST);glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MlN_FlLTER,GL_NEAREST);glTexlmage2D(GL_TEXTURE_2D,0,GL_RGBA,checklmageWidth,checklmageHeight,0,GL_RGBA,GL_UNSIGNED_BYTE,checklmage);glBindTexture(GL_TEXTURE_2D,texName1);glTexParame

8、teri(GL_TEXTURE_2D,GL_TEXTURE_WRAP_S,GL_CLAMP);glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_WRAP_T,GL_CLAMP);glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FlLTER,GL_NEAREST);glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MlN_FlLTER,GL_NEAREST);glTexEnvf(GL_TEXTURE_ENV,GL_TEXTURE_ENV_MODE,GL_DECAL);glTexlmage2D

9、(GL_TEXTURE_2D,0,GL_RGBA,checklmageWidth,checklmageHeight,0,GL_RGBA,GL_UNSlGNED_BYTE,otherlmage);glEnable(GL_TEXTURE_2D);voiddisplay(void)glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BlT);glBindTexture(GL_TEXTURE_2D,texName0);glBegin(GL_QUADS);glTexCoord2f(0.0,0.0);glVertex3f(-2.0,-1.0,0.0);glTexCoor

10、d2f(0.0,1.0);glVertex3f(-2.0,1.0,0.0);75.76.77.78.79.80.81.82.83.84.85.86.87.88.89.90.91.92.93.94.95.96.97.98.99.100.101.102.103.104.105.106.107.108.109.110.111.112.113.114.115.116.117.118.119.120.121.122.123.124.125.126.127.128.129.130.glTexCoord2f(1.0,1.0);glVertex3f(0.0,1.0,0.0);glTexCoord2f(1.0,

11、0.0);glVertex3f(0.0,-1.0,0.0);glEnd();glBindTexture(GL_TEXTURE_2D,texName1);glBegin(GL_QUADS);glTexCoord2f(0.0,0.0);glVertex3f(1.0,-1.0,0.0);glTexCoord2f(0.0,1.0);glVertex3f(1.0,1.0,0.0);glTexCoord2f(1.0,1.0);glVertex3f(2.41421,1.0,-1.41421);glTexCoord2f(1.0,0.0);glVertex3f(2.41421,-1.0,-1.41421);gl

12、End();glFlush();voidreshape(intw,inth)glViewport(0,0,(GLsizei)w,(GLsizei)h);glMatrixMode(GL_PROJECTION);glLoadIdentity();gluPerspective(60.0,(GLfloat)w/(GLfloat)h,1.0,30.0);glMatrixMode(GL_MODELVIEW);glLoadIdentity();glTranslatef(0.0,0.0,-3.6);voidkeyboardnsignedcharkey,intx,inty)switch(key)case27:e

13、xit(0);break;intmain(intargc,char*argv)glutInit(&argc,argv);glutInitDisplayMode(GLUT_SINGLE|GLUT_RGB|GLUT_DEPTH);glutInitWindowSize(250,250);glutInitWindowPosition(100,100);glutCreateWindow(argv0);init();glutReshapeFunc(reshape);glutDisplayFunc(display);glutKeyboardFunc(keyboard);glutMainLoop();return0;#elseintmain(intargc,char*argv)fprintf(stderr,Thisprogramde