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Hi, can anyone email me privately with the contact information for Jeff Stephenson? Or at least tell him that I’m looking for him? I am writing an essay on early PC game engines, and I would like to ask him some questions about the choices made when creating the graphics engine in AGI.
Or is there someone else I should try to contact?
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I don’t have any contact info for Jeff. Perhaps Ken does and will let you know (though the last list I had came from Ken). If you do find out his contact info, please let me know as well. Perhaps Ken or others here will have some insight on your questions if you post them here.
Brandon Klassen, archivist ~ SierraGamers.com admin/dev team ~
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Maybe Ken can indeed answer. I’ll ask the questions for Jim here (I’m sure he won’t mind 😉 ), but I’d also like to know.
– Why a resolution of 160×200 was chosen for the AGI engine, as it was created for the PCjr, and the PCjr was capable of displaying 320×200 with the same amount of colors (16). Was any porting to the Apple 2 (or maybe other machines like the C64) already planned at the time?
– At least in the Tandy 1000 version (not sure about the PCjr), the original King’s Quest and the following AGI games use the 320×200 resolution to display the 160×200 graphics, although the PCjr and Tandy 1000 machines feature a native 160x200x16 graphics mode. Why was this move taken, as it consumes more memory and makes the games slightly slower since twice as many pixels must be written? Was it to display the more-easily-readable 320×200 font?
– Was it considered at any point when developing the AGI engine for the PCjr, if Apple 2 conversion was planned, to have the resolution adaptable? Since the graphics are made of lines and region fills, it could have been possible to have the coordinates stored for 320×200, then the x coordinates divided by 2 for the Apple 2 and other 8-bit machines. Were there other issues involved that prevented from doing this in a reasonable (or even doable considering the deadline) time?
Thanks in advance for any recollection,
Vincent.
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“… (by Ken Williams) Sorry … I have no email address or phone number for Jeff Stephenson.
…”But still, Ken, do you have any clue about the questions above? Also, did the choices mentioned above had anything to do with what IBM wanted?
I have another question not directly technical. I was briefly in contact with a beta tester at IBM who tested the original King’s Quest before release. He told me they were 2 beta testers at IBM for King’s Quest. At the time, were you aware of the existance of these “external” beta testers? Did you have any contact with them, and did they bring any feedback about the game that could have shown in the final product?
Also, do you know who was responsible for the original PCjr packaging (cover, manual contents and graphics, original keyboard overlay)? Has it been done at Sierra or at IBM?
Thank you,
Vincent.
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– At least in the Tandy 1000 version (not sure about the PCjr), the original King’s Quest and the following AGI games use the 320×200 resolution to display the 160×200 graphics, although the PCjr and Tandy 1000 machines feature a native 160x200x16 graphics mode. Why was this move taken, as it consumes more memory and makes the games slightly slower since twice as many pixels must be written? Was it to display the more-easily-readable 320×200 font?
…”Hi Vincent, I have mucked around with the AGI games and written tools to extract the graphics from them and turn them into javascript stuff, so I know a bit about what goes on underneath.
The graphics take the same amount of space whether it is 160×200 or 320×200. Each pixel in the 320×200 graphics modes used in the AGI PC games simply is drawn 2 pixels wide. The AGI engine doesn’t store graphics as bitmaps, but drawing instructions – such as draw a red line from (0,0) to (100,100) then a circle etc. So I don’t think size was a problem. And since the screen is drawn once when it is loaded, speed wouldn’t have really been affected much either no matter what mode. Maybe it is just that the 320×200 mode is far more common (e.g. supported on CGA PC, Tandy and PC Jr).
Also of note to people interested in this is that it was possible to hack standard CGA colour card/RGB monitor setups (the four colour cyan, magenta etc setup) to display 8 or 16 colours at 160×200. If Sierra had known about this back in the day, there could’ve been a driver to get 16 colour AGI games running on CGA! This is probably most interesting to those who had to struggle through the AGI games with CGA (like me!).
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“… (by Ants Bull)
The graphics take the same amount of space whether it is 160×200 or 320×200. Each pixel in the 320×200 graphics modes used in the AGI PC games simply is drawn 2 pixels wide. The AGI engine doesn’t store graphics as bitmaps, but drawing instructions – such as draw a red line from (0,0) to (100,100) then a circle etc. So I don’t think size was a problem. …”So that’s indeed what I thought. Thanks for the confirmation!
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“… And since the screen is drawn once when it is loaded, speed wouldn’t have really been affected much either no matter what mode. …”Well, the speed was affected by the re-drawing of the sprites (characters, castle flags, etc.). The more and bigger the sprites, the slower the gameplay, at least on low-end machines such as the PCjr which is the slowest PC compatible in existence. Having a half-resolution would have freed bus bandwidth for the CPU (let me know if you’re interested in more details about this), and required to move half the data for sprites.
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“… Maybe it is just that the 320×200 mode is far more common (e.g. supported on CGA PC, Tandy and PC Jr). …”It’s true that the CGA BIOS does not support the 160×200 resolution. So maybe porting to CGA was considered right from the beginning of the development of the PCjr version?
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“… Also of note to people interested in this is that it was possible to hack standard CGA colour card/RGB monitor setups (the four colour cyan, magenta etc setup) to display 8 or 16 colours at 160×200. If Sierra had known about this back in the day, there could’ve been a driver to get 16 colour AGI games running on CGA! This is probably most interesting to those who had to struggle through the AGI games with CGA (like me!). …”Well, I’m glad to say Sierra *did* know about this back in the day! 😉
http://www.mobygames.com/game/pc-booter/kings-quest/screenshots
BTW, it does not work on RGB monitors, but on composite monitors.
Or maybe you’re talking about the 160×100 16-color “graphics” mode (which is a hacked text mode)?Vincent.
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