Lane-学习OpenGL(4)-4个进阶例子

来源：互联网发布：看高手如何做淘宝代销编辑：程序博客网时间：2024/05/21 12:47

运行环境:

(1)Windows 7

(2)CodeBlocks

(3)GLUT

(4)Author:Lane

2014-12-19

1.经过纹理贴图的棋盘

#include <windows.h>#include <GL/gl.h>#include <GL/glu.h>#include <GL/glut.h>#include <cstdlib>#include <cstdio>#include <cmath>#define checkImageWidth 64#define checkImageHeight 64static GLubyte checkImage[checkImageHeight][checkImageWidth][4];static GLuint texName;void makeCheckImage(void){    int i,j,c;    for(i = 0; i < checkImageHeight; i++){        for(j = 0; j < checkImageWidth; j++){            c = (((i&0x8)==0)^((j&0x8))==0)*255;            checkImage[i][j][0] = (GLubyte)c;            checkImage[i][j][1] = (GLubyte)c;            checkImage[i][j][2] = (GLubyte)c;            checkImage[i][j][3] = (GLubyte)255;        }    }}void init(void){    glClearColor(0.0,0.0,0.0,0.0);    glShadeModel(GL_FLAT);    glEnable(GL_DEPTH_TEST);    makeCheckImage();    glPixelStorei(GL_UNPACK_ALIGNMENT,1);    glGenTextures(1,&texName);    glBindTexture(GL_TEXTURE_2D,texName);    glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_WRAP_S,GL_REPEAT);    glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_WRAP_T,GL_REPEAT);    glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_NEAREST);    glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_NEAREST);    glTexImage2D(GL_TEXTURE_2D,0,GL_RGBA,checkImageWidth,checkImageHeight,0,GL_RGBA,GL_UNSIGNED_BYTE,checkImage);}void display(void){    glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);    glEnable(GL_TEXTURE_2D);    glTexEnvf(GL_TEXTURE_ENV,GL_TEXTURE_ENV_MODE,GL_REPLACE);    glBindTexture(GL_TEXTURE_2D,texName);    glBegin(GL_QUADS);        glTexCoord2f(0.0,0.0);        glVertex3f(-2.0,-1.0,0.0);        glTexCoord2f(0.0,1.0);        glVertex3f(-2.0,1.0,0.0);        glTexCoord2f(1.0,1.0);        glVertex3f(0.0,1.0,0.0);        glTexCoord2f(1.0,0.0);        glVertex3f(0.0,-1.0,0.0);        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);    glEnd();    glFlush();    glDisable(GL_TEXTURE_2D);}void reshape(int w,int h){    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);}int main(int argc,char** argv){    glutInit(&argc,argv);    glutInitDisplayMode(GLUT_SINGLE|GLUT_RGB|GLUT_DEPTH);    glutInitWindowSize(256,256);    glutInitWindowPosition(100,100);    glutCreateWindow(argv[0]);    init();    glutDisplayFunc(display);    glutReshapeFunc(reshape);    //glutKeyboardFunc(keyboard);    glutMainLoop();    return 0;}

2.替换纹理子图像

#include <windows.h>#include <GL/gl.h>#include <GL/glu.h>#include <GL/glut.h>#include <cstdlib>#include <cstdio>#include <cmath>#define checkImageWidth 64#define checkImageHeight 64#define subImageWidth 16#define subImageHeight 16static GLubyte checkImage[checkImageHeight][checkImageWidth][4];static GLubyte subImage[subImageHeight][subImageWidth][4];static GLuint texName;void makeCheckImage(void){    int i,j,c;    for(i = 0; i < checkImageHeight; i++){        for(j = 0; j < checkImageWidth; j++){            c = (((i&0x8)==0)^((j&0x8))==0)*255;            checkImage[i][j][0] = (GLubyte)c;            checkImage[i][j][1] = (GLubyte)c;            checkImage[i][j][2] = (GLubyte)c;            checkImage[i][j][3] = (GLubyte)255;        }    }    for(i = 0; i < subImageHeight; i++){        for(j = 0; j < subImageWidth; j++){            c = (((i&0x4)==0)^((j&0x4)==0)*255);            subImage[i][j][0] = (GLubyte)c;            subImage[i][j][1] = (GLubyte)0;            subImage[i][j][2] = (GLubyte)0;            subImage[i][j][3] = (GLubyte)255;        }    }}void keyboard(unsigned char key,int x,int y){    switch(key){        case 's':        case 'S':            glBindTexture(GL_TEXTURE_2D,texName);            glTexSubImage2D(GL_TEXTURE_2D,0,12,44,                            subImageWidth,subImageHeight,GL_RGBA,                            GL_UNSIGNED_BYTE,subImage);            glutPostRedisplay();            break;        case 'r':        case 'R':            glBindTexture(GL_TEXTURE_2D,texName);            glTexImage2D(GL_TEXTURE_2D,0,GL_RGBA,                         checkImageWidth,checkImageHeight,0,                         GL_RGBA,GL_UNSIGNED_BYTE,checkImage);            glutPostRedisplay();            break;        case 27:            exit(0);            break;        default:            break;    }}void init(void){    glClearColor(0.0,0.0,0.0,0.0);    glShadeModel(GL_FLAT);    glEnable(GL_DEPTH_TEST);    makeCheckImage();    glPixelStorei(GL_UNPACK_ALIGNMENT,1);    glGenTextures(1,&texName);    glBindTexture(GL_TEXTURE_2D,texName);    glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_WRAP_S,GL_REPEAT);    glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_WRAP_T,GL_REPEAT);    glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_NEAREST);    glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_NEAREST);    glTexImage2D(GL_TEXTURE_2D,0,GL_RGBA,checkImageWidth,checkImageHeight,0,GL_RGBA,GL_UNSIGNED_BYTE,checkImage);}void display(void){    glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);    glEnable(GL_TEXTURE_2D);    glTexEnvf(GL_TEXTURE_ENV,GL_TEXTURE_ENV_MODE,GL_REPLACE);    glBindTexture(GL_TEXTURE_2D,texName);    glBegin(GL_QUADS);        glTexCoord2f(0.0,0.0);        glVertex3f(-2.0,-1.0,0.0);        glTexCoord2f(0.0,1.0);        glVertex3f(-2.0,1.0,0.0);        glTexCoord2f(1.0,1.0);        glVertex3f(0.0,1.0,0.0);        glTexCoord2f(1.0,0.0);        glVertex3f(0.0,-1.0,0.0);        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);    glEnd();    glFlush();    glDisable(GL_TEXTURE_2D);}void reshape(int w,int h){    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);}int main(int argc,char** argv){    glutInit(&argc,argv);    glutInitDisplayMode(GLUT_SINGLE|GLUT_RGB|GLUT_DEPTH);    glutInitWindowSize(256,256);    glutInitWindowPosition(100,100);    glutCreateWindow(argv[0]);    init();    glutDisplayFunc(display);    glutReshapeFunc(reshape);    glutKeyboardFunc(keyboard);    glutMainLoop();    return 0;}

3.使用求值器进行纹理处理

#include <windows.h>#include <GL/gl.h>#include <GL/glu.h>#include <GL/glut.h>#include <cstdlib>#include <cstdio>#include <cmath>GLfloat ctrlpoints[4][4][3] = {    {{-1.5,-1.5,4.0},{-0.5,-1.5,2.0},     {0.5,-1.5,-1.0},{1.5,-1.5,2.0}},    {{-1.5,-0.5,1.0},{-0.5,-0.5,3.0},     {0.5,-0.5,0.0},{1.5,-0.5,-1.0}},    {{-1.5,0.5,4.0},{-0.5,0.5,0.0},     {0.5,0.5,3.0},{1.5,0.5,4.0}},    {{-1.5,-1.5,-2.0},{-0.5,1.5,-2.0},     {0.5,1.5,0.0},{1.5,1.5,-1.0}}};GLfloat texpts[2][2][2]={{{0.0,0.0},{0.0,1.0}},{{1.0,0.0},{1.0,1.0}}};void display(void){    glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);    glColor3f(1.0,1.0,1.0);    glEvalMesh2(GL_FILL,0,20,0,20);    glFlush();}#define imageWidth 64#define imageHeight 64GLubyte image[3*imageWidth*imageHeight];void makeImage(void){    int i,j;    float ti,tj;    for(i = 0; i < imageWidth;i++){        ti = 2.0 * 3.14159265*i/imageWidth;        for(j = 0; j < imageHeight; j++){            tj = 2.0 * 3.14169265*j/imageHeight;            image[3*(imageHeight*i+j)]=(GLubyte)127*(1.0+sin(ti));            image[3*(imageHeight*i+j)]=(GLubyte)127*(1.0+cos(2*tj));            image[3*(imageHeight*i+j)+2]=(GLubyte)127*(1.0+cos(ti+tj));        }    }}void init(void){    glMap2f(GL_MAP2_VERTEX_3,0,1,3,4,0,1,12,4,&ctrlpoints[0][0][0]);    glMap2f(GL_MAP2_TEXTURE_COORD_2,0,1,2,2,0,1,4,2,&texpts[0][0][0]);    glEnable(GL_MAP2_TEXTURE_COORD_2);    glEnable(GL_MAP2_VERTEX_3);    glMapGrid2f(20,0.0,1.0,20,0.0,1.0);    makeImage();    glTexEnvf(GL_TEXTURE_ENV,GL_TEXTURE_ENV_MODE,GL_DECAL);    glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_WRAP_S,GL_REPEAT);    glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_WRAP_T,GL_REPEAT);    glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_NEAREST);    glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_NEAREST);    glTexImage2D(GL_TEXTURE_2D,0,3,imageWidth,imageHeight,0,GL_RGB,GL_UNSIGNED_BYTE,image);    glEnable(GL_TEXTURE_2D);    glEnable(GL_DEPTH_TEST);    glShadeModel(GL_FLAT);}void reshape(int w,int h){    glViewport(0,0,(GLsizei)w,(GLsizei)h);    glMatrixMode(GL_PROJECTION);    glLoadIdentity();    if(w <= h)        glOrtho(-4.0,4.0,-4.0*(GLfloat)h/(GLfloat)w,4.0*(GLfloat)h/(GLfloat)w,-4.0,4.0);    else        glOrtho(-4.0*(GLfloat)w/(GLfloat)h,4.0*(GLfloat)w/(GLfloat)h,-4.0,4.0,-4.0,4.0);    glMatrixMode(GL_MODELVIEW);    glLoadIdentity();    glRotatef(35.0,1.0,1.0,1.0);}int main(int argc,char** argv){    glutInit(&argc,argv);    glutInitDisplayMode(GLUT_SINGLE|GLUT_RGB|GLUT_DEPTH);    glutInitWindowSize(500,500);    glutInitWindowPosition(100,100);    glutCreateWindow(argv[0]);    init();    glutDisplayFunc(display);    glutReshapeFunc(reshape);    glutMainLoop();    return 0;}

4.NURBS表面

#include <windows.h>#include <GL/gl.h>#include <GL/glu.h>#include <GL/glut.h>#include <cstdlib>#include <cstdio>#include <cmath>#ifdef CALLBACK#define CALLBACK#endif // CALLBACKGLfloat ctlpoints[4][4][3];int showPoints = 0;GLUnurbsObj *theNurb;void init_surface(void){    int u,v;    for(u=0;u<4;u++){        for(v=0;v<4;v++){            ctlpoints[u][v][0]=2.0*((GLfloat)u-1.5);            ctlpoints[u][v][1]=2.0*((GLfloat)v-1.5);            if((u==1||u==2)&&(v==1||v==2))                ctlpoints[u][v][2]=3.0;            else                ctlpoints[u][v][2]=-3.0;        }    }}void CALLBACK nurbsError(GLenum errorCode){    const GLubyte *estring;    estring = gluErrorString(errorCode);    fprintf(stderr,"Nurbs Error:%s \n ",estring);    exit(0);}void init(void){    GLfloat mat_diffuse[] = {0.7,0.7,0.7,1.0};    GLfloat mat_specular[] = {1.0,1.0,1.0,1.0};    GLfloat mat_shininess[] = {100.0};    glClearColor(0.0,0.0,0.0,0.0);    glMaterialfv(GL_FRONT,GL_DIFFUSE,mat_diffuse);    glMaterialfv(GL_FRONT,GL_SPECULAR,mat_specular);    glMaterialfv(GL_FRONT,GL_SHININESS,mat_shininess);    glEnable(GL_LIGHTING);    glEnable(GL_LIGHT0);    glEnable(GL_DEPTH_TEST);    glEnable(GL_AUTO_NORMAL);    glEnable(GL_NORMALIZE);    init_surface();    theNurb = gluNewNurbsRenderer();    gluNurbsProperty(theNurb,GLU_SAMPLING_TOLERANCE,25.0);    gluNurbsProperty(theNurb,GLU_DISPLAY_MODE,GLU_FILL);    gluNurbsCallback(theNurb,GLU_ERROR,(void (__stdcall *)(void))nurbsError);}void display(void){    GLfloat knots[8]={0.0,0.0,0.0,0.0,1.0,1.0,1.0,1.0};    int i,j;    glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);    glPushMatrix();    glRotatef(330.0,1.0,0.0,0.0);    glScalef(0.5,0.5,0.5);    gluBeginSurface(theNurb);    gluNurbsSurface(theNurb,8,knots,8,knots,4*3,8,&ctlpoints[0][0][0],4,4,GL_MAP2_VERTEX_3);    gluEndSurface(theNurb);    if(showPoints){        glPointSize(5.0);        glDisable(GL_LIGHTING);        glColor3f(1.0,1.0,0.0);        glBegin(GL_POINTS);        for(i=0;i<4;i++){            for(j=0;j<4;j++){                glVertex3f(ctlpoints[i][j][0],ctlpoints[i][j][1],ctlpoints[i][j][2]);            }        }        glEnd();        glEnable(GL_LIGHTING);    }    glPopMatrix();    glFlush();}void reshape(int w,int h){    glViewport(0,0,(GLsizei)w,(GLsizei)h);    glMatrixMode(GL_PROJECTION);    glLoadIdentity();    gluPerspective(45.0,(GLdouble)w/(GLdouble)h,3.0,8.0);    glMatrixMode(GL_MODELVIEW);    glLoadIdentity();    glTranslatef(0.0,0.0,-5.0);}void keyboard(unsigned char key,int x,int y){    switch(key){        case 'c':        case 'C':            showPoints = !showPoints;            glutPostRedisplay();            break;        case 27:            exit(0);            break;        default:            break;    }}int main(int argc,char** argv){    glutInit(&argc,argv);    glutInitDisplayMode(GLUT_SINGLE|GLUT_RGB|GLUT_DEPTH);    glutInitWindowSize(500,500);    glutInitWindowPosition(100,100);    glutCreateWindow(argv[0]);    init();    glutReshapeFunc(reshape);    glutDisplayFunc(display);    glutKeyboardFunc(keyboard);    glutMainLoop();    return 0;}

0 0