Stecil shadow

    glDisable(GL_LIGHTING);    glDisable(GL_TEXTURE_2D);                glClearStencil(0);    glEnable(GL_CULL_FACE);    glDepthMask(GL_FALSE);    glColorMask(0,0,0,0);    glEnable(GL_STENCIL_TEST);    glStencilFunc(GL_ALWAYS, 1, 1);    glFrontFace(GL_CCW);    glStencilOp(GL_KEEP, GL_KEEP, GL_INCR);        spiral.cast_shadow_volume(lightPos[0],lightPos[1],lightPos[2], inv_matice_objektu);        glFrontFace( GL_CW );    glStencilOp(GL_KEEP, GL_KEEP, GL_DECR);        spiral.cast_shadow_volume(lightPos[0],lightPos[1],lightPos[2], inv_matice_objektu);        glColorMask(1,1,1,1);    glStencilFunc(GL_NOTEQUAL, 0, 1);    glStencilOp(GL_KEEP, GL_KEEP, GL_KEEP );        glPushMatrix();     glLoadIdentity();     glBegin(GL_QUADS);      glVertex3f(-1.0, -1.0,-1.0);     glVertex3f(-1.0,1.0,-1.0);     glVertex3f( 1.0, 1.0,-1.0);     glVertex3f( 1.0,-1.0,-1.0);   glEnd();   glPopMatrix();        glFrontFace(GL_CCW);    glEnable(GL_LIGHTING);    glEnable(GL_TEXTURE_2D);    glDisable(GL_STENCIL_TEST);        glDepthMask(GL_TRUE);

void OBJEKT::cast_shadow_volume(float lx,float ly,float lz, GLmatrix16f &objMat) {    POINT sv(lx,ly,lz);    POINT light;    svetlo=sv.B_trans_Matrix(objMat);    VECTOR a,b;    POINT A,B;    int v1,v2;    for (int i=0;i<face_count;i++) {                        if (plane.ExBodD(light)>0.0) {                                faces.enlighted=1;        }                if (plane.ExBodD(light)<0.0) {                                faces.enlighted=0;        }    }            for (int i=0;i<face_count;i++) {                if (faces.enlighted) {                                  for (int j=0;j<3;j++) {                                          if (!faces[faces.neigh_index[j]].enlighted) {                                                                       v1=faces.vert_index[j];                     v2=faces.vert_index[(j+1)%3];                                          a=vertexes[v1].V_A_to_B(light);                     b=vertexes[v2].V_A_to_B(light);                     a.unit();                     b.unit();                                          a.KxV(60.0);                     b.KxV(60.0);                                          A=vertexes[v1].move_ret_B(a);                     B=vertexes[v2].move_ret_B(b);                                                                                  glBegin (GL_TRIANGLE_STRIP);                     glVertex3f(vertices[v1].X,vertices[v1].Y,vertices[v1].Z);                     glVertex3f(A.X,A.Y,A.Z);                     glVertex3f(vertices[v2].X,vertices[v2].Y,vertices[v2].Z);                      glVertex3f(B.X,B.Y,B.Z);                                     glEnd();                                                                                  }                     }                                                                              } else {};           }    }