Modifying a value above the stack pointer doesn't seem to make much
sense. This was added in FreeSCI back in 2002 in a pair of commits that
did not make clear what the purpose of this was. My guess is that it
attempted to adjust argc, but failed. This wouldn't have been noticed
since argc was always set correctly by make_exec_stack_entry (which is
now the ExecStack constructor).
ExecStack now stores the kernel call number as well as the subfunction.
This allows kStub and backtraces to log the actual subfunction called.
The kernel call number in ExecStack used to be stored in the
debugSelector field. It now has its own field, to avoid confusion.
The way dimensions of scaled screen items are calculated changed
over the lifetime of SSCI. In early low-resolution and
mixed-resolution games, scaled drawing needed to use at a global
cadence across the entire screen to ensure proper alignment, but
in later games (like Torin), local scaling of individual screen
items seems to be the way scaling is performed.
Using the one from SCI2.1mid makes fades very slow because SDL has
a larger audio buffer than SSCI DOS. This new algorithm is based on
wall time so will always fade at the correct speed, although the
larger buffers will have a coarser granularity so the fades may
not be as smooth as in the original engine. If anyone cares, the
fade volume could be mixed into individual samples in `readBuffer`
instead of applying just once per complete buffer. SSCI did not
do this, however, so this implementation should be pretty accurate.
Overlays are shown with _currentShakePos offset too, so no need to
compensate the mousepointer position for overlays. This compensation
was done inconsistently in draw/undraw mouse causing the mouse trails.
Remap would crash SCI2.1early games with 19 remap slots, and
did not actually work in most cases in SCI2.1mid+ games.
1. Avoid accidental corruption of values from the VM that may be
valid when signed or larger than 8 bits
2. Fix bad `matchColor` function.
3. Remove unnecessary initialisation of SingleRemaps
4. Update architecture to more closely mirror how SSCI worked
5. Split large `apply` function into smaller units
6. Fix buffer overrun when loading a SCI2.1early game with remap
7. Warn instead of crashing with an error on invalid input (to
match SSCI more closely)
8. Add save/load function
This pass exposed two bugs, which have been fixed:
1. Checks of `_updated` and `_moved` were reversed in some areas,
which lead to rendering bugs. In SQ6 the rendering bugs were
subtle or non-existant, but in e.g. PQ:SWAT the Sierra logo and
title screen animations were totally missing.
2. The renderer formerly kept reading from ScreenItemLists when
new items were added in decrementScreenItemArrayCounts, but
this was determined to be unnecessary.
It seems highly probable that there are later SCI games that use
the "hi res" rendering path, so sorting and unsorting of
ScreenItemLists needs to be accurate.
Command input stays disabled, when oiling the arm of the armor.
We fix this.
This script bug also happens, when using the original interpreter.
Fixes bug #7154
SSCI implementation of the SYSDATE subop of the GetTime kernel function was
changed between SCI0-LATE and SCI01: The base year used was changed from 1920 to
1980.
This subop is used in "Codename: Iceman" (Say "ask for date" to a passing girl
on the beach).
The Atari ST version of "Codename: Iceman" use the 1980 base year.
The Amiga version of "Codename: Iceman" appears to return the time instead of
date, with 0 for the YEAR part.
Remap would crash SCI2.1early games with 19 remap slots, and
did not actually work in most cases in SCI2.1mid+ games.
The SCI16 implementation was moved to its own separate file but
was otherwise touched as little as possible, so may still have
similar problems to the SCI32 code.
1. Split SCI16 and SCI32 code into separate files
2. Use -32 prefixes for SCI32 code and no prefix for SCI16 code,
where possible, to match other existing code
3. Avoid accidental corruption of values from the VM that may be
valid when signed or larger than 8 bits
4. Added documentation
5. Add missing remap CelObj calls
6. Inline where possible in performance-critical code paths
7. Fix bad `matchColor` function, and move it from GfxPalette to
GfxRemap32 since it is only used by GfxRemap32
8. Fix bad capitalisation in getCycleMap
9. Remove unnecessary initialisation of SingleRemaps
10. Update architecture to more closely mirror how SSCI worked
11. Clarify the purpose of each type of remap type (and
associated variable names)
12. Split large `apply` function into smaller units
13. Fix buffer overrun when loading a SCI2.1early game with remap
14. Remove use of `#define` constants
15. Warn instead of crashing with an error on invalid input (to
match SSCI more closely)
16. Change the collision avoidance mechanism between the RemapType
enum and remap kernel functions
17. Add save/load function
The Spanish version of Myst has bitmaps that use palette indices in the system
reserved range. Affected pixels previously used colors from the Windows system
palette instead of the bitmap's own palette, resulting in visual glitches.
Bitmaps are now remapped to the screen palette which is made of the Windows
reserved palette and part of the bitmap palette. The original engine used GDI's
StretchDIBits with DIB_RGB_COLORS to achieve the same result.
Fixes#7153.
Script patch to change the fixed slot 999 to fixed slot 99 in the
game scripts and additional code for kSaveGame, that checks for
Cascade Quest + slot 99 and will then use ScummVM slot 0, which
is our auto-save slot.
Fixes bug #7007
Also added the game name to the other fan-made script patch.
Willem Jan Palenstijn
Ori Avtalion
Colin Snover
Martin Kiewitz
Ben Castricum
Filippos Karapetis
Omer Mor
Bastien Bouclet