Hello, Ive been working on an Occlusion culler that uses opengl's occlusion queries

although when I render the scene meshes can occlude meshes but when models are in front of each other they still render.

here is the code

void renderer::draw()
{
 for( int m = 0; m < renderer::meshes.size(); m++ )
    {
	 glPushMatrix();
	  if(renderer::meshes[m].yaw != 0 )
	    glRotatef(renderer::meshes[m].yaw,1.0,0.0,0.0);
	  
	  if(renderer::meshes[m].pitch != 0 )		
	    glRotatef(renderer::meshes[m].pitch,0.0,1.0,0.0); 
	  
	  if(renderer::meshes[m].roll != 0 )
	    glRotatef(renderer::meshes[m].roll,0.0,0.0,1.0);
	 
	 if((renderer::meshes[m].scaley != 1)&&(renderer::meshes[m].scaley != 1)&&(renderer::meshes[m].scalez != 1))
	    glScalef(renderer::meshes[m].scaley,renderer::meshes[m].scaley,renderer::meshes[m].scalez);
	 
	 if((renderer::meshes[m].x != 0)&&(renderer::meshes[m].y != 0)&&(renderer::meshes[m].z != 0))	 	
        glTranslatef(renderer::meshes[m].x,renderer::meshes[m].y,renderer::meshes[m].z);	
	 
	 for( int l = 0; l < renderer::meshes[m].trislists.size(); l++ )
        {
         glGenQueriesARB( 1, &renderer::meshes[m].trislists[l].query );
         glBeginQueryARB( GL_SAMPLES_PASSED_ARB, renderer::meshes[m].trislists[l].query);
		 for( int t = 0; t < renderer::meshes[m].trislists[l].tris.size(); t++ )
             {   
              drawtriangle(renderer::meshes[m].trislists[l].tris[t]);
             }
		 glEndQueryARB( GL_SAMPLES_PASSED_ARB );
		}
	 glPopMatrix();
    }
 glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT );
  
 for( int m = 0; m < renderer::meshes.size(); m++ )
    {
	 for( int l = 0; l < renderer::meshes[m].trislists.size(); l++ )
        {
		 glGetQueryObjectuivARB( renderer::meshes[m].trislists[l].query, GL_QUERY_RESULT_ARB, &renderer::meshes[m].trislists[l].fragmentcount);
		}
    }  
  
for( int m = 0; m < renderer::meshes.size(); m++ )
    {
	 glPushMatrix();
	  if(renderer::meshes[m].yaw != 0 )
	    glRotatef(renderer::meshes[m].yaw,1.0,0.0,0.0);
	  
	  if(renderer::meshes[m].pitch != 0 )		
	    glRotatef(renderer::meshes[m].pitch,0.0,1.0,0.0); 
	  
	  if(renderer::meshes[m].roll != 0 )
	    glRotatef(renderer::meshes[m].roll,0.0,0.0,1.0);
	 
	 if((renderer::meshes[m].scaley != 1)&&(renderer::meshes[m].scaley != 1)&&(renderer::meshes[m].scalez != 1))
	    glScalef(renderer::meshes[m].scaley,renderer::meshes[m].scaley,renderer::meshes[m].scalez);
	 
	 if((renderer::meshes[m].x != 0)&&(renderer::meshes[m].y != 0)&&(renderer::meshes[m].z != 0))	 	
        glTranslatef(renderer::meshes[m].x,renderer::meshes[m].y,renderer::meshes[m].z);	
	 
	 for( int l = 0; l < renderer::meshes[m].trislists.size(); l++ )
        {
		if(renderer::meshes[m].trislists[l].fragmentcount != 0 )
		  {
		   glPolygonMode( GL_FRONT_AND_BACK, GL_LINE );
         //draw
         for( int t = 0; t < renderer::meshes[m].trislists[l].tris.size(); t++ )
             {         
              drawtriangle(renderer::meshes[m].trislists[l].tris[t]);
		     }
		   glPolygonMode( GL_FRONT_AND_BACK, GL_FILL );
		  }
		  
		  
		}
	 glPopMatrix();
    }

 //clear
 renderer::meshes.clear();
}

I think you misunderstand, what occ queries are. They render the mesh just as if they were disabled. You do not query if they were visible, but rather if any fragments were rendered.If you happen to render your meshes back to front, then every mesh will pass the test, because every mesh renders new fragments. Also, requesting the results of a query can and in your case will stall the gpu, which severely degrades the performance. Even if your code was working, you would still render everything at least once, thus having no gain, and in addition stall the gpu in midframe.

The best advice to give at this point is this: don't use occ queries for occlusion tests, at least not without conditional rendering.