             body_force[ilocal].z = fi.z;
             body_force[ilocal].w = fi.w;
             
-            /*
-            ri.x = pos.x - com.x;
-            ri.y = pos.y - com.y;
-            ri.z = pos.z - com.z;
-            
-            float x_shift = rintf(ri.x * box.Lxinv);
-            ri.x -= box.Lx * x_shift;
-            float y_shift = rintf(ri.y * box.Lyinv);
-            ri.y -= box.Ly * y_shift;
-            float z_shift = rintf(ri.z * box.Lzinv);
-            ri.z -= box.Lz * z_shift;
-            
-            if (ri.x >= box.Lx/2.0) ri.x -= box.Lx;
-            else if (ri.x <= -box.Lx/2.0) ri.x += box.Lx;
-            if (ri.y >= box.Ly/2.0) ri.y -= box.Ly;
-            else if (ri.y <= -box.Ly/2.0) ri.y += box.Ly;            
-            if (ri.z >= box.Lz/2.0) ri.z -= box.Lz;
-            else if (ri.z <= -box.Lz/2.0) ri.z += box.Lz;
-            */
-            
+                     
             // This might require more calculations but more stable
             ri.x = ex_space.x * particle_pos.x + ey_space.x * particle_pos.y 
                     + ez_space.x * particle_pos.z;

                                                                                             nmax,
                                                                                             window_size,
                                                                                             box);
    else gpu_rigid_force_sliding_kernel<<< force_grid, force_threads, 2 * window_size * sizeof(float4) >>>(rigid_data.force, 
                                                                                             rigid_data.torque, 
                                                                                             n_bodies, 
                                                                                             local_beg,
                                                                                             nmax,
                                                                                             window_size,
                                                                                             box);       
    if (!g_gpu_error_checking)
        {
        return cudaSuccess;
        }

            rdata_torque[idx_body] = torque2;
            }
        }
*/
    int idx_body = blockIdx.x + local_beg;
    
    float4 *body_force = sum;
    float4 *body_torque = &sum[window_size];
    
    float4 ri, ex_space, ey_space, ez_space, particle_pos;
    float4 fi = make_float4(0.0f, 0.0f, 0.0f, 0.0f);
    float4 torquei = make_float4(0.0f, 0.0f, 0.0f, 0.0f);
    float4 force2 = make_float4(0.0f, 0.0f, 0.0f, 0.0f); 
    float4 torque2 = make_float4(0.0f, 0.0f, 0.0f, 0.0f); 
    
	ex_space = tex1Dfetch(rigid_data_exspace_tex, idx_body);
	ey_space = tex1Dfetch(rigid_data_eyspace_tex, idx_body);
	ez_space = tex1Dfetch(rigid_data_ezspace_tex, idx_body);
			
    unsigned int n_windows = nmax / window_size;
    
    // slide the window throughout the block
    for (unsigned int start = 0; start < n_windows; start++)
		{
        body_force[threadIdx.x] = make_float4(0.0f, 0.0f, 0.0f, 0.0f);
        body_torque[threadIdx.x] = make_float4(0.0f, 0.0f, 0.0f, 0.0f);
        fi = make_float4(0.0f, 0.0f, 0.0f, 0.0f);
		torquei = make_float4(0.0f, 0.0f, 0.0f, 0.0f);
		
		int idx_particle = idx_body * nmax + start * window_size + threadIdx.x;
		unsigned int idx_particle_index = tex1Dfetch(rigid_data_particle_indices_tex, idx_particle);
				     
        if (idx_body < n_bodies && idx_particle_index != INVALID_INDEX && idx_particle < nmax)
            {
            // calculate body force and torques
			particle_pos = tex1Dfetch(rigid_data_particle_pos_tex, idx_particle);
			fi = tex1Dfetch(net_force_tex, idx_particle_index);
							
            body_force[threadIdx.x].x = fi.x;
            body_force[threadIdx.x].y = fi.y;
            body_force[threadIdx.x].z = fi.z;
            body_force[threadIdx.x].w = fi.w;
            
            // This might require more calculations but more stable
            ri.x = ex_space.x * particle_pos.x + ey_space.x * particle_pos.y 
                    + ez_space.x * particle_pos.z;
            ri.y = ex_space.y * particle_pos.x + ey_space.y * particle_pos.y 
                    + ez_space.y * particle_pos.z;
            ri.z = ex_space.z * particle_pos.x + ey_space.z * particle_pos.y 
                    + ez_space.z * particle_pos.z;

            torquei.x = ri.y * fi.z - ri.z * fi.y;
            torquei.y = ri.z * fi.x - ri.x * fi.z;
            torquei.z = ri.x * fi.y - ri.y * fi.x;
            torquei.w = 0.0;
            
            body_torque[threadIdx.x].x = torquei.x;
            body_torque[threadIdx.x].y = torquei.y;
            body_torque[threadIdx.x].z = torquei.z;
            body_torque[threadIdx.x].w = torquei.w;
            }
            
        __syncthreads();

        // reduction within the current window
        unsigned int offset = window_size >> 1;
        while (offset > 0)
            {
            if (threadIdx.x < offset)
                {
                body_force[threadIdx.x].x += body_force[threadIdx.x + offset].x;
                body_force[threadIdx.x].y += body_force[threadIdx.x + offset].y;
                body_force[threadIdx.x].z += body_force[threadIdx.x + offset].z;
                body_force[threadIdx.x].w += body_force[threadIdx.x + offset].w;
                
                body_torque[threadIdx.x].x += body_torque[threadIdx.x + offset].x;
                body_torque[threadIdx.x].y += body_torque[threadIdx.x + offset].y;
                body_torque[threadIdx.x].z += body_torque[threadIdx.x + offset].z;
                body_torque[threadIdx.x].w += body_torque[threadIdx.x + offset].w;
                }
                
            offset >>= 1;
            
            __syncthreads();
            }
        
        // accumulate the body force into the thread-local variables
        force2.x += body_force[0].x;
        force2.y += body_force[0].y;
        force2.z += body_force[0].z;
        force2.w += body_force[0].w;
        
        torque2.x += body_torque[0].x;
        torque2.y += body_torque[0].y;
        torque2.z += body_torque[0].z;
        torque2.w += body_torque[0].w;
        
        __syncthreads();
		}
        
    if (idx_body < n_bodies)
        {
        if (threadIdx.x == 0)
            {
            rdata_force[idx_body] = force2;
            rdata_torque[idx_body] = torque2;
            }
        }

			
    }

/*! \param pdata Particle data to step forward 1/2 step
