// table of node visible faces, 0 = invisible
			int visible_faces[6] = {0,0,0,0,0,0};

			// table of neighbours, 1 = same type, checked with g_26dirs
			int nb[18] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};

			// g_26dirs to check when only horizontal merge is allowed
			int nb_H_dirs[8] = {0,2,3,5,10,11,12,13};

			u8 i;
			content_t current = n.getContent();
			content_t n2c;
			MapNode n2;
			v3s16 n2p;

			// neighbours checks for frames visibility

			if (!H_merge && V_merge) {
				n2p = blockpos_nodes + p + g_26dirs[1];
				n2 = data->m_vmanip.getNodeNoEx(n2p);
				n2c = n2.getContent();
				if (n2c == current || n2c == CONTENT_IGNORE)
					nb[1] = 1;
				n2p = blockpos_nodes + p + g_26dirs[4];
				n2 = data->m_vmanip.getNodeNoEx(n2p);
				n2c = n2.getContent();
				if (n2c == current || n2c == CONTENT_IGNORE)
					nb[4] = 1;
			} else if (H_merge && !V_merge) {
				for(i = 0; i < 8; i++) {
					n2p = blockpos_nodes + p + g_26dirs[nb_H_dirs[i]];
					n2 = data->m_vmanip.getNodeNoEx(n2p);
					n2c = n2.getContent();
					if (n2c == current || n2c == CONTENT_IGNORE)
						nb[nb_H_dirs[i]] = 1;
				}
			} else if (H_merge && V_merge) {
				for(i = 0; i < 18; i++)	{
					n2p = blockpos_nodes + p + g_26dirs[i];
					n2 = data->m_vmanip.getNodeNoEx(n2p);
					n2c = n2.getContent();
					if (n2c == current || n2c == CONTENT_IGNORE)
						nb[i] = 1;
				}
			}

			// faces visibility checks

			if (!V_merge) {
				visible_faces[0] = 1;
				visible_faces[1] = 1;
			} else {
				for(i=0; i<2; i++) {
					n2p = blockpos_nodes + p + dirs[i];
					n2 = data->m_vmanip.getNodeNoEx(n2p);
					n2c = n2.getContent();
					if (n2c != current)
						visible_faces[i]=1;
				}
			}

			if (!H_merge) {
				visible_faces[2] = 1;
				visible_faces[3] = 1;
				visible_faces[4] = 1;
				visible_faces[5] = 1;
			} else {
				for(i=2; i<6; i++) {
					n2p = blockpos_nodes + p + dirs[i];
					n2 = data->m_vmanip.getNodeNoEx(n2p);
					n2c = n2.getContent();
					if (n2c != current)
						visible_faces[i]=1;
				}
			}