opengl lightning problem by skyke

1

void CView::lightSettings( void ) {     GLfloat light_diffuse []={ 1.0, 1.0, 1.0, 1.0 };     GLfloat light_ambient []={ 0.2, 0.2, 0.2, 1.0 };     GLfloat light_spec []={ 1.0, 1.0, 1.0, 1.0 };     GLfloat spot_direction[] = { 0.0, -1.0, 0.0 };          glLightfv ( GL_LIGHT0, GL_AMBIENT_AND_DIFFUSE, light_diffuse );     glLightfv ( GL_LIGHT0, GL_SPECULAR, light_spec );     glLightf(GL_LIGHT0, GL_CONSTANT_ATTENUATION, 1.0);     glLightf(GL_LIGHT0, GL_LINEAR_ATTENUATION, 0.0);     glLightf(GL_LIGHT0, GL_QUADRATIC_ATTENUATION, 0.0006);     glLightf(GL_LIGHT0, GL_SPOT_CUTOFF, 90.0);     glLightfv(GL_LIGHT0, GL_SPOT_DIRECTION, spot_direction);     GLfloat lmodel_ambient[] = { 0.0, 1.0, 0.0, 1.0 }; }         lightSettings();     glEnable( GL_LIGHTING );     glEnable( GL_LIGHT0 );     glEnable(GL_DEPTH_TEST);     glEnable(GL_TEXTURE_2D);     glEnable( GL_POLYGON_SMOOTH );         GLfloat light0_position [] = {0.0f, 0.0f, 0.0f, 1.0f};     glLightfv ( GL_LIGHT0, GL_POSITION, light0_position );