Opened 9 years ago
Closed 6 years ago
#7122 closed defect (fixed)
SCI: Hoyle3 Amiga - kGetFarText Crash
| Reported by: | OmerMor | Owned by: | bluegr |
|---|---|---|---|
| Priority: | normal | Component: | Engine: SCI |
| Version: | Keywords: | ||
| Cc: | Game: | Hoyle's Book of Games 3 |
Description
Game: Hoyle Official Book of Games Volume 3 Game Version: Amiga/ENGLISH ScummVM Version: 1.8.0 Operating System: Windows 10
ScummVM crashes when a character tries to speak during a game. I verified that the game is not corrupt and WAI in an Amiga emulator.
The fault is when GetFarText kernel function is called from char1::say:
char1::say(4, 0, 443, 1) kGetFarText(3300, 4, 00d:0058)
Here's a decompilation of the relevant part from Character::say (script #0):
(cond
( (u< param1 100)
(if active
; This is the case that crashed. temp501 is represents
; the text resource number:
; temp501 = gGNewRoomNumber + 1000*(view + 1)
(= temp501 (+ (* 1000 (+ view 1)) gGNewRoomNumber))
(= temp502 param1)
else
(= temp501 (+ 19000 gGNewRoomNumber))
(= temp502 (/ param1 3))
)
(GetFarText temp501 temp502 @temp1)
(= param1 (Format @global550 0 0 @temp1))
(= temp503 (if (> argc 1) param2 else 0))
)
( (u< param1 1000)
(GetFarText [param1 0] [param1 1] @temp1)
(= param1 (Format @global550 0 0 @temp1))
(= temp503 (if (> argc 2) [param1 2] else 0))
)
)
The scripts tries to access text resource 3300 which is mapped from room 300 (backgammon) and character view 2 (Rosella), using the following formula:
textResource = room + 1000*(view + 1)
In this case, room = 300 and view = 2, so we get text resource 3300.
The text resources in the DOS version are indeed numbered according to the scheme described in the script. However, the Amiga version has no text resource #3300.
I compared the text resources of the Amiga version with those in the DOS version, and noticed they are numbered differently. The Amiga version use a different numbering scheme which I was able to reconstruct:
textResource = room - 24*(view + 1) + 1024*((view + 1)%2)
Somehow the Amiga interpreter "knows" to retrieve the correct resource number, even though the script is using the DOS numbering scheme. Possible explanation could be a translation in the kernel function. Another explanation could be that there are multiple instances of SCRIPT.000 in the resource file, and ScummVM uses the wrong one (similar to bug #5141, https://github.com/scummvm/scummvm/commit/864b067f).
Ticket imported from: bugs/7122.
Attachments (1)
Change History (6)
comment:1 by , 9 years ago
comment:2 by , 9 years ago
You're right! I failed to see it...
I have some more information: I tried to patch scummvm to fallback to the "amiga scheme" if the text resource is not found. It made the game workable for backgammon+rosella (room 300, view 2). However when trying checkers+mordack (room 200, view 11) it failed to find text resource 960. I checked with both SCI Companion and Sierra Viewer, and this text resource is "invisible" to them as well.
Again, checking with an emulator I verified that the game is WAI, so clearly this text resource is there. This suggests we're not handling amiga resources correctly, and maybe there is a "hidden" SCRIPT.000 as well that has the correct text numbering scheme.
comment:3 by , 9 years ago
| Component: | → Engine: SCI |
|---|---|
| Game: | → Hoyle's Book of Games 3 |
comment:4 by , 7 years ago
The Amiga version of Hoyle 3 is... strange. Texts are stored as either text, font or palette types. Seems like the resource type bits are used as part of the resource numbers. I haven't found a reliable way of loading these correctly as text in the resource manager, so the least invasive way of loading them properly, that I could think of, is in Kernel::lookupText()
I'm attaching a patch that makes Hoyle 3 Amiga fully playable, with the following changes:
- Handling of game texts for this game
- Skipping a reference to an invalid export function 0 in script 601, when the script is loaded (this is the script for Snakes and Ladders)
- Enabling of the entry in the detector
If someone can think of a cleaner way to handle these resources properly in the resource manager, feel free to adapt this patch accordingly :)
comment:5 by , 6 years ago
| Owner: | set to |
|---|---|
| Resolution: | → fixed |
| Status: | new → closed |
The patch for Hoyle 3 Amiga has now been merged on master and the game works, so I'm closing this as fixed
Unless I am mistaken, your reconstructed formula just looks like applying the 0x7FF mask to the DOS text resource number: amigaTextResource = dosTextResource & 0x7FF