一段资料书上的opengl入门实例，运行时只是黑屏，没有效果，急，帮忙看看，感激不尽

[yxh015864]

#include <windows.h>
#include <gl/gl.h>
#include <gl/glut.h>


static GLfloat xrot=0.0f; //旋转参数
static GLfloat yrot=0.0f;
GLboolean round=1; //多边形绕法；

void setup() //初始化窗口
{
glClearColor(0.0f,0.0f,0.0f,1.0f);
}

void change(GLfloat w,GLfloat h) //窗口改变函数
{
if(h==0) h=1;
glViewport(0,0,w,h); //屏幕视图

glMatrixMode(GL_PROJECTION); //重置坐标系
glLoadIdentity();

if (w<=h) //修剪区
{
glOrtho(-100.0f,100.0f,-100.0f*h/w,100.0f*h/w,-100.0f,100.0f);
}
else
glOrtho(-100.0f*w/h,100.0f*w/h,-100.0f,100.0f,-100.0f,100.0f);
glMatrixMode(GL_MODELVIEW); //影响修改
glLoadIdentity();
}

void show() //初始显示函数
{
glClear(GL_COLOR_BUFFER_BIT);
glPushMatrix(); //增加旋转
glRotatef(xrot,1.0f,0.0f,0.0f);
glRotatef(yrot,0.0f,1.0f,0.0f);

glPointSize(5); //点大小及线宽
glLineWidth(5);

if(round==1) glFrontFace(GL_CW);
else glFrontFace(GL_CCW);

glBegin(GL_TRIANGLES);
glColor3f(0.0f,1.0f,0.0f);
glVertex3f(30,60,0);
glColor3f(1.0f,0.0f,0.0f);
glVertex3f(-60,-60,0);
glColor3f(0.0f,0.0f,1.0f);
glVertex3f(60,-60,0);
glEnd();

glPopMatrix();
glutSwapBuffers(); //刷新缓冲区
}

void keys(int key,int x,int y) //响应按键函数
{
if(key==GLUT_KEY_UP) xrot-=5.0f;
if(key==GLUT_KEY_DOWN) xrot+=5.0f;
if(key==GLUT_KEY_LEFT) yrot-=5.0f;
if(key==GLUT_KEY_RIGHT) yrot+=5.0f;

if(xrot>356.0f) xrot=0.0f;
if(xrot<-1.0f) xrot=355.0f;
if(yrot>356.0f) yrot=0.0f;
if(yrot<-1.0f) yrot=355.0f;

glutPostRedisplay(); //刷新窗口
}
void menu(int value) //响应菜单函数
{
switch (value)
{
case 1:
glPolygonMode(GL_FRONT,GL_FILL); //正面填充，线，点 模式
break;
case 2:
glPolygonMode(GL_FRONT,GL_LINE);
break;
case 3:
glPolygonMode(GL_FRONT,GL_POINT);
break;
case 4:
glPolygonMode(GL_BACK,GL_FILL); //反面填充，线，点 模式
break;
case 5:
glPolygonMode(GL_BACK,GL_LINE);
break;
case 6:
glPolygonMode(GL_BACK,GL_POINT);
break;
case 7:
glShadeModel(GL_FLAT); //阴影平面模式
break;
case 8:
glShadeModel(GL_SMOOTH); // 阴影光滑模式
break;
case 9:
if(round==1) round=0;
else round =1;
break;
default:
break;
}
glutPostRedisplay();
}

int main(int argc,char* argv[])
{
int modeM;
int mainM;
int colM;

glutInit(&argc,argv);
glutInitDisplayMode(GLUT_DOUBLE|GLUT_RGB);
glutCreateWindow("旋转");
glutDisplayFunc(show);
glutReshapeFunc(change);
glutSpecialFunc(keys);

modeM = glutCreateMenu(menu); //创建菜单
glutAddMenuEntry("正面填充",1);
glutAddMenuEntry("正面线框",2);
glutAddMenuEntry("正面点型",3);
glutAddMenuEntry("反面填充",4);
glutAddMenuEntry("反面线框",5);
glutAddMenuEntry("反面点型",6);

colM = glutCreateMenu(menu);
glutAddMenuEntry("平面模式",7);
glutAddMenuEntry("光滑模式",8);

mainM = glutCreateMenu(menu);

glutAddSubMenu("多边形模式",modeM);
glutAddSubMenu("颜色模式",colM);
glutAddMenuEntry("绕法",9);

glutAttachMenu(GLUT_RIGHT_BUTTON); //右键关联

setup();
glutMainLoop();
return 0;
}

[我才是心翼]

我也时候刚学不久~
我感觉是不是少个glFlush()啊？但是你用的双缓冲，那么你的Show()函数位置是不是调用没弄好？

另外觉得你的头文件里面好像俩GL有点重了

[yxh015864]

[Quote=引用 1 楼 doctorwing 的回复:]
我也时候刚学不久~
我感觉是不是少个glFlush()啊？但是你用的双缓冲，那么你的Show()函数位置是不是调用没弄好？

另外觉得你的头文件里面好像俩GL有点重了
[/Quote]

要不你直接把这段代码运行下，好像有的机器上能出来效果，郁闷。。。

[yxh015864]

原来 change函数的参数要改成int。。。函数要求很严格啊。。。谢谢关注

[我才是心翼]

客气，没帮上忙，我也学习了