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-- For what it's worth: /** Rant on **/ The 5250 graphics orders were a "bolt on" to the original 5250 twinax data-stream. The terminal had to send back PF key scan codes after processing the orders (the technical reasons as I recall had to do with twinax timing requirements vs the technology available for raster-scan conversion). This added a fair amount of complexity to applications using the data stream. This may well have been a technology 'ahead of it's time', that got rushed into place to meet late breaking requirement in the S/36 Release 1 delivery. By the time the product hit the street the stand-alone terminal was on the order of $7K. The original PC 5250 emulation (and later DOS based PC Support and DOS CA) implementations required loading sizable drivers in DOS, that were VERY dependent on the display characteristics (for around $5K). And the resulting graphics (at least on the early PC displays) suffered the predictable "stairstep" effects, and were drawn relatively slowly (even with a then speedy 80386). This support pre-dated SAA's definitions for a "common" set of graphic orders. If I remember correctly, Windows 3.0 and later incarnations came with faster graphic drawing capabilities (that might have made writing a terminal emulator easier, to say nothing of easier to set up and use). The point is the memory requirements were big, and the setup difficult -- and you had a 320x680 pel display(!!??). It might have been interesting to see what this could have done on a more graphic oriented personal workstation -- a MAC of the era comes to mind! Despite several COMMON requirements, dating back to the first Win '95 and OS/2 based terminal emulators IBM refused to make the investment needed to bring the S/38 and AS/400 GDDM support forward to more capable workstations. I suspect the GDDM host support has not progressed far beyond the GDDM V1 capability used on the S/38 CPF Release 6 (when it was originally released). The last time I looks (and this was several years ago) GDDM on TSO/VM/MVS was at version 4 or 5 with some significant functional additions. I have heard that IBM plans to remove the 5250 graphics and drop GDDM support on the iSeries in a future release (as in very near future release). Pity -- the GDDM on the MVS/VM environments got so they could REALLY produce decent graphics. /** Rant off **/ Using current GUI/HTML capabilities on PC's some outstanding graphics applications were (and still could be written) using GDDM -- if the link was in place. As it is, GDDM provides a reasonably usable (and device independent architecture) for an application to create decent graphics. I understand that there is a LINUX 5250 emulation -- it might be interesting to explore what it would take for that emulator to "crack" the 5250 graphics orders! George Lemen Strategic Solutions Inc. e-mail: george@strategicsol.com; phone (425) 462-6446 personal: georgelemen@seanet.com; cell phone (206) 419-6225 ---------- From: Steve Richter[SMTP:srichter@AutoCoder.com] Reply To: mi400@midrange.com Sent: Friday, November 02, 2001 12:25 PM To: mi400@midrange.com Subject: Re: [MI400] 5250 graphics Jim, others: The 5250 data stream has what looks to be a rich set of graphics orders. GDDM is implemented using these orders. Graphics orders are a very efficient way to transmit graphics to a display. They are programmer friendly and device independent. Example orders: Draw a bar chart, place grid lines around a subfile listing, shade the top area of the screen, gray the bottom half. Display file DDS is a very good vehicle for coding graphics orders. Telnet 5250 ( tn5250 ) is an open internet standard. It, along with tn3270, look to be the most feature rich of the telnet specs ( by far ). The iSeries is the best Telnet server on the market. ( also by far ) Telnet has great connectivity options. You can client connect to the server from dumb terminals, palm devices, and pc's. I will stop now, because I am not selling anything. My question had to do with technical aspects of 5250 graphics orders. But I dont think very functional features should be written off so quickly. -Steve Richter ----- Original Message ----- From: "Jim Langston" <jlangston@celsinc.com> To: <mi400@midrange.com> Sent: Friday, November 02, 2001 12:04 PM Subject: RE: [MI400] 5250 graphics Hmm.. for that matter, why couldn't you write your own API to do graphics, which would change the way they were transmitted dependant on what device the user was using? If they were using a GDDM capable device send the data that way, otherwise send using IP socket to some VB client that would display them? The answer, I think, is the same reason GDDM died, not much need for it. Regards, Jim Langston -----Original Message----- From: thomas@inorbit.com [mailto:thomas@inorbit.com] Sent: Thursday, November 01, 2001 7:28 PM To: mi400@midrange.com Subject: RE: [MI400] 5250 graphics Njål: On Thu, 01 November 2001, "Njål Fisketjøn" wrote: > Why burden the AS/400 to "do" the graphics, when you can easily write > a client server app to make the PC do it? > > And why bother learning "stone age" API's (GDDM), when you can use VB, Java > or some other PC-based language? You're right in both respects. Yet, there are reasons for both. The immediate simple responses that come to mind are that GDDM is available for free on AS/400s all over the world and that MI has a difficult time calling VB programs adequately. Also keep in mind that GDDM can be used to create printed graphics; i.e., a 5292 graphics workstation is not required for output. Maybe the best reason of all for this list is simply... it feels pretty cool when you make it work! Tom Liotta -- Tom Liotta The PowerTech Group, Inc. 19426 68th Avenue South Kent, WA 98032 Phone 253-872-7788 Fax 253-872-7904 http://www.400Security.com _______________________________________________ This is the MI Programming on the AS400 / iSeries (MI400) mailing list To post a message email: MI400@midrange.com To subscribe, unsubscribe, or change list options, visit: http://lists.midrange.com/cgi-bin/listinfo/mi400 or email: MI400-request@midrange.com Before posting, please take a moment to review the archives at http://archive.midrange.com/mi400. _______________________________________________ This is the MI Programming on the AS400 / iSeries (MI400) mailing list To post a message email: MI400@midrange.com To subscribe, unsubscribe, or change list options, visit: http://lists.midrange.com/cgi-bin/listinfo/mi400 or email: MI400-request@midrange.com Before posting, please take a moment to review the archives at http://archive.midrange.com/mi400. -- [ Content of type application/ms-tnef deleted ] --
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