From herzner@zdfzs.arcs.ac.at Mon Jan 23 14:53:33 1995 Received: from zdvaxf.arcs.ac.at by dkuug.dk with SMTP id AA04793 (5.65c8/IDA-1.4.4j for ); Mon, 23 Jan 1995 19:51:54 +0100 Received: by zdfzs.arcs.ac.at (MX V4.1 VAX) id 3; Mon, 23 Jan 1995 19:53:34 EST Date: Mon, 23 Jan 1995 19:53:33 EST From: "Wolfgang Herzner OeFZS/Dep.IT +43 2254 780 3121" To: SC24@dkuug.dk Cc: herzner@zdfzs.arcs.ac.at Message-Id: <0098AE83.77E05618.3@zdfzs.arcs.ac.at> Subject: MHEG DIS letter ballot X-Charset: ASCII X-Char-Esc: 29 Dear member of SC24, as liaison officer to SC29/WG12, I want to inform you that the letter ballot on ISO/IEC DIS 13522-1 "MHEG object representation - base notation (ASN.1)" is now out and terminates on 1995-04-15. The document can be received via ftp 129.63.24.2/pub/MHEG/DIS where you will find the following files: total 7794 -rw-r----- 1 79 1026 1326958 Jan 5 07:44 DIS-1.ps.gz -rw-r--r-- 1 79 1026 139238 Oct 17 12:54 DIS-1.rtf.gz -rw-r----- 1 79 1026 1335533 Jan 5 07:48 DIS-2.ps.gz -rw-r--r-- 1 79 1026 193807 Oct 17 13:10 DIS-2.rtf.gz -rw-r----- 1 79 1026 803993 Jan 5 07:52 DIS-3.ps.gz -rw-r--r-- 1 79 1026 117011 Oct 17 13:17 DIS-3.rtf.gz -rw-r----- 1 79 1026 171 Jan 5 05:35 README Since the rtf appear pretty old, refer to the *.ps.gz files (gzipped). I will bring your special attention to chapter 53 (persumably in DIS-2.ps.gz), which describes spatial behaviour. It is a pretty complex model, but appears relatively 'unclean' to me with respect to SC24's way to handle simple spatial transformations (e.g. in revised GKS). Another aspect is that MHEG does not support rotation of (content) objects before display, not to mention perspective views, although 3 spatial dimensions are supported. The basic reason is the restriction that content should be presentable with minimal rendering effort as possible ('final form'). However, stretching (parallel to coordinate axes) appears to be supported. The question is if this restriction is a crucial defect SC24 (e.g. PREMO when looking at MHEG as interchange format at the display level) cannot live with. Best regards Wolfgang Herzner ---------------------------------------------------------------------- Wolfgang R. Herzner Dep. Information Technology (IT) Austrian Research Centre Seibersdorf A-2444 Seibersdorf tel: +43 2254 780 3121 (secr.: 3118) fax: +43 2254 74060 e-mail: herzner@zdfzs.arcs.ac.at OR herzner@zdfzs.una.ac.at or PSI%0232-26221064::HERZNER X.400: C=CAT; A=ADA; P=ARCS; S=HERZNER ----------------------------------------------------------------------