OpenGL导入3ds模型的问题

[dontforgetaboutus]

本人用lib3ds导入模型后 采用最原始的画三角形的方法遍历模型中所有的点，画出模型 但在光照的时候出现模型表面有很多杂斑（enable了深度缓存）请问 如何去除杂斑？而且如果在场景中添加一个地板 地板会覆盖部分模型（奇怪的是我激活了depth buffer）

code：

#include <windows.h>
#include <gl/glee.h>
#include <gl/gl.h>
#include <gl/glu.h>
#include <gl/glut.h>
#include <lib3ds.h>
#include <iostream>

typedef float Lib3dsVector[3];
typedef float Lib3dsTexel[2];
using namespace std;

Lib3dsFile* model;
Lib3dsMesh** mesh;
Lib3dsCamera** camera;
Lib3dsFace* face;
Lib3dsLight** light;
Lib3dsMaterial** material;
GLuint vertexVBO,normalVBO,textureVBO;

unsigned long total_face;

void lightup()
{
glShadeModel(GL_SMOOTH);
glEnable(GL_DEPTH_TEST);
glEnable(GL_CULL_FACE);
glFrontFace(GL_CCW);
float gambient[]={0.2,0.2,0.2,1.0};
float lightpos[]={1.0,1.0,1.0,0.0};
float lambient[]={1.0,1.0,1.0,1.0};
float ldiffuse[]={0.8,0.8,0.8,1.0};
float lspecular[]={0.3,0.3,0.3,1.0};

glLightfv(GL_LIGHT0,GL_DIFFUSE,ldiffuse);
glLightfv(GL_LIGHT0,GL_AMBIENT,lambient);
glLightfv(GL_LIGHT0,GL_SPECULAR,lspecular);
glLightfv(GL_LIGHT0,GL_POSITION,lightpos);
glLightModelfv(GL_LIGHT_MODEL_AMBIENT,gambient);
glEnable(GL_LIGHTING);
glEnable(GL_LIGHT0);
}

void getfaces()
{
total_face=0;
for(long meshcount=0;meshcount<model->nmeshes;meshcount++)
total_face+=mesh[meshcount]->nfaces;
}

void display()
{
glEnable(GL_DEPTH_TEST);
glClearDepth(1.0);
glDepthFunc(GL_LEQUAL);

glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BITS);
glLoadIdentity();
gluLookAt(camera[0]->position[0]+1000,camera[0]->position[1],camera[0]->position[2],camera[0]->target[0],camera[0]->target[1],camera[0]->target[2],0.0,0.0,1.0);

glColor3f(1.0,0.0,0.0);
glPushMatrix();
lightup();
glScalef(0.5,0.5,0.5);
glTranslatef(0.0,0.0,-1000.0);
long meshcount;
for(meshcount=0;meshcount<model->nmeshes;meshcount++)
{
face=mesh[meshcount]->faces;
for(long i=0;i<mesh[meshcount]->nfaces;i++)
{
glMaterialfv(GL_FRONT,GL_DIFFUSE,material[face[i].material]->diffuse);
glMaterialfv(GL_FRONT,GL_AMBIENT,material[face[i].material]->ambient);
glMaterialfv(GL_FRONT,GL_SPECULAR,material[face[i].material]->specular);
glBegin(GL_TRIANGLES);
glVertex3fv(mesh[meshcount]->vertices[face[i].index[0]]);
glVertex3fv(mesh[meshcount]->vertices[face[i].index[1]]);
glVertex3fv(mesh[meshcount]->vertices[face[i].index[2]]);
glEnd();
}
}

glPopMatrix();
/*画地板
glPushMatrix();
glTranslatef(0.0,0.0,-2000.0);
glColor3f(1.0,1.0,1.0);
glBegin(GL_QUADS);
glVertex3f(-10000.0f,-10000.0f,0.0f);
glVertex3f(10000.0f,-10000.0f,0.0f);
glVertex3f(10000.0f,10000.0f,0.0f);
glVertex3f(-10000.0f,10000.0f,0.0f);
glEnd();
glPopMatrix();
*/

glutSwapBuffers();
}

void keypress(unsigned char key,int x,int y)
{
switch(key)
{
case 27:
exit(0);
break;
}
}
void reshape(int w,int h)
{
if(h==0) h=1;
glViewport(0,0,w,h);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluPerspective(45.0,w/h,0.0,1000.0);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
}
int main(int argc,char* argv[])
{

glutInit(&argc,argv);
model=lib3ds_file_open("vehicle.3DS");
if(model==NULL) cout<<"Error"<<endl; else cout<<model->nmaterials<<endl;
mesh=model->meshes;
material=model->materials;
camera=model->cameras;
light=model->lights;
cout<<"Light Num:"<<model->nlights<<endl;



glutInitDisplayMode(GLUT_RGB|GLUT_DOUBLE|GLUT_DEPTH);
glutInitWindowSize(800,800);
glutInitWindowPosition(100,100);
glutCreateWindow("VC 2008 Glut");
//glutFullScreen();
glShadeModel(GL_FLAT);
glutKeyboardFunc(keypress);
glutDisplayFunc(display);
glutReshapeFunc(reshape);
glutMainLoop();
return 0;
}