Raydium 3D Game Engine

raydium_texture_current_set_name("texture.tga");
raydium_rendering_internal_prepare_texture_render(raydium_texture_current_main);
glColor4fv(raydium_background_color);

raydium_rendering_internal_restore_render_state()
glColor4fv(raydium_background_color);

void raydium_atmosphere_create_sphere(GLfloat x, GLfloat y, GLfloat z,int detail)
{   
   int i, j;   
   //keeping safe the current matrix
   glPushMatrix();
   glLoadIdentity();   
   
   glDisable(GL_LIGHTING);
   glDisable(GL_FOG);
   raydium_rendering_internal_restore_render_state() ;
   glColor4fv(raydium_background_color);
   glDepthMask(GL_FALSE);
   
   //making the sphere
    for(i = 0; i <= detail; i++)
   {
      double lat0    =   M_PI * (-0.5 + (double) (i - 1) / (double)detail);
      double z0       =   sin(lat0);
      double zr0      =   cos(lat0);          
      double lat1      =   M_PI * (-0.5 + (double) i / (double)detail);
      double z1      =   sin(lat1);
      double zr1      =   cos(lat1);
       
      //we create a pair of vertex, that will be used to make QUADs
      glBegin(GL_QUAD_STRIP);
      for(j = 0; j <= detail; j++)
      {   
         double lng = 2 * M_PI * (double) (j - 1) / (double)detail;
         double xx = cos(lng);
         double yy = sin(lng);
         //vertex 1
         glColor4f(1,1,1,1);
         glNormal3f(-xx * zr0, -yy * zr0, -z0);
         glVertex3f(-xx * zr0, -yy * zr0, -z0);
         //vertex2
         glColor4f(1,1,0,1);
         glNormal3f(xx * zr1, yy * zr1, z1);
         glVertex3f(xx * zr1, yy * zr1, z1);
         
      }
        glEnd();
   }
   //making the sphere is always in tha same place that the camera
   //i'd like to do this internally, w/o pass the x,y,z in the params
   //of the function.
   glTranslatef(x,y,z);
   
   //restoring previus states
   if(raydium_light_enabled_tag) glEnable(GL_LIGHTING);
   if(raydium_fog_enabled_tag) glEnable(GL_FOG);
   glDepthMask(GL_TRUE);
   glPopMatrix();
}

glPushMatrix();
glLoadIdentity();
drawing
glTranslate();
glPopMatrix();

//internal
void raydium_sky_sphere_render(GLfloat x, GLfloat y, GLfloat z,int detail)
{   
   int i, j;
   GLfloat currentradious,z1,z2,ang1;
   GLfloat p[detail+1][detail+1][3];
   
   //keeping safe the current matrix
   glPushMatrix();   
   angle1+=0.2;
   angle2+=0.02;
   glDisable(GL_LIGHTING);
   glDisable(GL_FOG);
   raydium_rendering_internal_prepare_texture_render(raydium_texture_current_main);
   raydium_rendering_internal_restore_render_state() ;
   glColor4fv(raydium_background_color);
   glDepthMask(GL_FALSE);
   
   //MAKING THE SPHERE
   
   //getting the points of the sphere, but no drawing
   for(i=0;i<=detail;i++)
   {
      //getting the radious for each section of the sphere
      currentradious      =   raydium_trigo_sin(180*((float)i/(float)detail));
      //getting the heights for each section of the sphere
      z1               =   raydium_trigo_cos(180*((float)i/(float)detail));      
      for(j=0;j<=detail;j++)
      {
         ang1   =   360*((float)j/(float)detail);
         p[i][j][0]   =   currentradious * raydium_trigo_cos(ang1);
         p[i][j][1]   =   currentradious * raydium_trigo_sin(ang1);
         p[i][j][2]   =   z1;
      }
   }
   //now drawing with the obtained values
   glTranslatef(x,y,z);
   glRotatef(angle2,0,0,1);
   glRotatef(angle1,1,0,0);
   for(i=0;i<detail;i++)
   {
      for(j=0;j<detail;j++)
      {
         //z1=0.5+p[i][j][2]/(float)2;
         //z2=0.5+p[i+1][j][2]/(float)2;
         z1=1-(float)i/detail;
         z2=1-(float)(i+1)/detail;
         glBegin(GL_TRIANGLES);
         //glColor4f(1,0,0,1);
         glColor3f(z1,z1,z1);
         glVertex3f(p[i][j][0],p[i][j][1],p[i][j][2]);
         //glColor4f(0,1,0,1);
         glColor4f(z1,z1,z1,1);
         glVertex3f(p[i][j+1][0],p[i][j+1][1],p[i][j+1][2]);
         //glColor4f(1,0,1,1);
         glColor4f(z2,z2,z2,1);
         glVertex3f(p[i+1][j][0],p[i+1][j][1],p[i+1][j][2]);
         //glColor4f(1,0,0,1);
         glColor4f(z2,z2,z2,1);
         glVertex3f(p[i+1][j][0],p[i+1][j][1],p[i+1][j][2]);
         //glColor4f(0,1,0,1);
         glColor4f(z2,z2,z2,1);
         glVertex3f(p[i+1][j+1][0],p[i+1][j+1][1],p[i+1][j+1][2]);
         //glColor4f(1,0,1,1);
         glColor4f(z1,z1,z1,1);
         glVertex3f(p[i][j+1][0],p[i][j+1][1],p[i][j+1][2]);
         glEnd();
      }
   }

   //restoring previus states
   if(raydium_light_enabled_tag) glEnable(GL_LIGHTING);
   if(raydium_fog_enabled_tag) glEnable(GL_FOG);
   glDepthMask(GL_TRUE);
   glPopMatrix();
}