OpenGL：立方体形状上缺少阴影

当我使用以下阵列时，为什么阴影会从立方体形状的未照亮面消失：

vertices[] 
indices[] 
colors[] 
normals[] 
texcoords[] 
// and draw them by
glDrawElements();

但当我使用：

glBegin(...);
 glVertex3f(...);
glEnd(...); 

阴影还可以。 在这里，您可以看到正在发生的事情：

我的灯光设置如下：

glShadeModel (GL_SMOOTH);
glEnable(GL_LIGHTING);
glEnable(GL_LIGHT0);
glEnable(GL_DEPTH_TEST);
glColorMaterial( GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE);
glEnable(GL_COLOR_MATERIAL);        
glHint (GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST);

GLfloat AmbientLight[] = {0.0, 0.0, 0,0, 1.0};
GLfloat DiffuseLight[] = {1.0, 1.0, 1,0, 1.0};
GLfloat SpecularLight[] = {1.0, 1.0, 1.0, 1.0};
GLfloat Shininess[] = { 90.0 };
GLfloat Emission[] = {0.0, 0.0, 0.0, 1.0};

glLightfv(GL_LIGHT0, GL_AMBIENT, AmbientLight);
glLightfv(GL_LIGHT0, GL_DIFFUSE, DiffuseLight);
glLightfv(GL_LIGHT0, GL_SPECULAR, SpecularLight);
glMaterialfv(GL_FRONT_AND_BACK, GL_AMBIENT, AmbientLight);
glMaterialfv(GL_FRONT_AND_BACK, GL_DIFFUSE, DiffuseLight);
glMaterialfv(GL_FRONT_AND_BACK, GL_SPECULAR, SpecularLight);
glMaterialfv(GL_FRONT_AND_BACK, GL_SHININESS, Shininess);
glMaterialfv(GL_FRONT_AND_BACK, GL_EMISSION, Emission);

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你可能错过了一个电话

glEnableClientState( GL_NORMAL_ARRAY );

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什么阴影？这两幅图像都没有显示任何类似阴影的内容，只是一个立方体面和圆形对象的不同阴影。