In the original engine this would have simply resulted in no draw,
but ScummVM is more strict about it. It is not 100% clear whether
these are normal and should be allowed or not, so for the moment
we'll emit a warning whenever a zero-dimension show rect is seen.
For now they only seem to be generated by plane transitions, and
these zero-dimension screen items cannot simply be omitted because
the 2.1early transitions code requires a fixed number of screen
items per step.
This commit implements all of the known plane transitions from
SCI2 through SCI2.1mid games. Because kSetShowStyle is always
called indirectly via the Styler game script, it is difficult to
find all the places where transitions are used. As such,
transitions that appeared to never be used have been added as
stubs which will trigger a game crash with a message to report
what was being done, so any missed transition types can be
identified quickly and then implemented.
Bitmaps in ScrollWindow and Robot code are managed by the kernel
and not by game scripts, although they must be able to be
referenced through a reg_t. To prevent incorrect GC of bitmaps
that are in use but not referenced by any game script, explicit
memory management of hunk entries can be enabled.
1. Use the same throttling speed as normal frameouts. The
old throttling speed seemed a bit too slow.
2. Exit the event loop immediately if the engine is supposed to
quit, instead of forcing the user to wait until the transition
has finished before quitting.
Some games load palettes that include color 255, but this is
hardcoded to white in SSCI, so just ignore it during merges since
it is ignored when the hardware palette is updated anyway.
Avoid forcing the screen to refresh after a palette change if the
screen is also about to be drawn to, as the palette change + draw
is intended to be an atomic operation.
With the addition of the transparent pic type code, the _type
property would be read uninitialised by setType if _pictureId was
set to kPlanePic.
CID 1357230, 1357231.
Sometimes, games accidentally use palette entries that are not
marked as used and expect them to be a particular colour, like the
Phantasmagoria title screen, or the white palette entry (always
255 in DOS/Win).
Controls that manage their own event loops and call frameOut
directly generally need to sleep in order to avoid 100% CPU,
just like the main VM event loop.
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.
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.
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
Most of the time, we get a bitmap to draw on it. Exposing a buffer
avoids consumers having to create their own all the time, and
encourages use of common drawing code exposed by the buffer.
1. Inline borderSize constant in createFontBitmap for consistency
2. Fix "DrawTextBox GetLongest=0" warning to only appear in games
that actually had this check (SQ6 and MGDX)
3. "Fix" implementation of getTextSize for SCI2.1early, which
gave lines with word wrap disabled a height of 0
4. Add inlining hints to some methods in BitmapResource that were
missing them for some reason
This kernel call seems only to be used by KQ7 1.51 (which was
Windows-only) to send warnings to the user.
It was easy enough to do a basic implementation in the ScummVM
GUI rather than just make it an empty call, so now it is a thing.
Eugene Sandulenko
Colin Snover
Willem Jan Palenstijn