Question about Sierra AGI engine support level

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Digitoxin
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Question about Sierra AGI engine support level

Post by Digitoxin »

I noticed that the support level for all Sierra AGI games is at Good. What is still missing or not working correctly with these games that is preventing them from getting a support level of Excellent?
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Praetorian
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Re: Question about Sierra AGI engine support level

Post by Praetorian »

Digitoxin wrote: Thu Oct 14, 2021 1:29 am I noticed that the support level for all Sierra AGI games is at Good. What is still missing or not working correctly with these games that is preventing them from getting a support level of Excellent?
I think in general we reserved the "excellent" level for engines for which the original game developers made the source code available to us, and there are no missing features or known game breaking bugs. But, I believe that the rules for this grading were not really set in stone, so probably a few engines may have been promoted to Excellent without access the original source code; the developers felt confident enough that they were complete. We do of course get bug reports from time to time even for "Excellent" game engines.

There have been some short discussions, that I've read, about potentially changing this system to another with a more clear distinction between the levels.
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Raziel
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Re: Question about Sierra AGI engine support level

Post by Raziel »

Maybe also because the many fan games aren't 100% supported either?
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sev
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Re: Question about Sierra AGI engine support level

Post by sev »

We only relatively recently reworked the drawing routines, but still, there are occasional glitches, especially when games depended on slow computers. And yes, some fangames still have glitches and nobody yet confirmed if those exist in the original or are brought by ScummVM's implementation.

And finally, we still lack support for AGI0 and AGI1, which are booters, thus, the engine is incomplete.
thethreeheadedmonkey
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Re: Question about Sierra AGI engine support level

Post by thethreeheadedmonkey »

Also accurate emulation of CGA with composite colours and CGA with RGB dithering. What you currently get when selecting "CGA" in AGI games, with those ugly pink/magenta colours, is more of a "glitch" than an actual representation of what gamers with either CGA option would have seen back then.
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MusicallyInspired
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Re: Question about Sierra AGI engine support level

Post by MusicallyInspired »

thethreeheadedmonkey wrote: Fri Oct 15, 2021 4:19 pm Also accurate emulation of CGA with composite colours and CGA with RGB dithering. What you currently get when selecting "CGA" in AGI games, with those ugly pink/magenta colours, is more of a "glitch" than an actual representation of what gamers with either CGA option would have seen back then.
But I still think it's important to preserve that behaviour. Having both behaviours would be the best case scenario. Like playing in DOSBox with machine type set to "cga" and playing with machine type set to "vga". Not to mention Composite CGA which is a whole other ball of wax...but yeah, I can understand why it's not at "excellent" yet for all of these reasons.
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sev
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Re: Question about Sierra AGI engine support level

Post by sev »

thethreeheadedmonkey wrote: Fri Oct 15, 2021 4:19 pm Also accurate emulation of CGA with composite colours and CGA with RGB dithering. What you currently get when selecting "CGA" in AGI games, with those ugly pink/magenta colours, is more of a "glitch" than an actual representation of what gamers with either CGA option would have seen back then.
In fact, it is not a glitch. CGA on an RGB colour monitor with composite input at those times was a big rarity and for most people, it was that ugly pink/magenta or brown/yellow. But indeed, it would be nice to implement the composite CGA output for AGI too.


Eugene
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Re: Question about Sierra AGI engine support level

Post by thethreeheadedmonkey »

sev wrote: Mon Oct 18, 2021 11:38 am In fact, it is not a glitch. CGA on an RGB colour monitor with composite input at those times was a big rarity and for most people, it was that ugly pink/magenta or brown/yellow. But indeed, it would be nice to implement the composite CGA output for AGI too.


Eugene

Which is why Sierra added a dithered CGA RGB mode for users who didn't have a composite monitor at their disposal. AFAIK these were the ONLY two CGA options in Sierra's AGI games: either composite or dithered RGB. And it certainly wasn't pink/magenta.
See http://nerdlypleasures.blogspot.com/201 ... quest.html for images of the dithered CGA RGB mode.
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