void discardTempData(boolean discardAll) {
		voxelData = null;
		if (dataType == SURFACE_FILE)
			try {
				br.close();
			}
			catch (Exception e) {
			}
		if (!discardAll)
			return;
		assocGridPointMap = null;
		assocGridPointNormals = null;
		pixelData = null;
		planarSquares = null;
		contourVertexes = null;
		contourVertexCount = 0;
	}