[Scummvm-tracker] [ScummVM :: Bugs] #12039: MMC64: Graphical glitch with alien in telescope

[ScummVM :: Bugs]

#12039: MMC64: Graphical glitch with alien in telescope
-------------------+----------------------------
Reporter:  dp304   |      Owner:  (none)
    Type:  defect  |     Status:  new
Priority:  normal  |  Component:  Engine: SCUMM
Keywords:          |       Game:  Maniac Mansion
-------------------+----------------------------
 Debian 10 x86_64
 ScummVM 2.0.0
 Maniac Mansion C64/English

 The graphics are corrupted when the alien appears in the telescope, see
 screenshot.

 To reproduce: load the attached save game, and use really powerful
 telescope.

 This may be due to a corruption in the disk image, but apparently disk
 images from different download sources are identical in this regard: in
 `MANIAC2.D64`, at offset `0x29fff` (i.e. within the pic map of Room 35),
 there is a `0x4B` value, which should rather be `0x82`.

 (Btw. this would also cause a buffer overrun by 24 bytes in ScummVM, if it
 weren't for the extra space allocated for `GdiV1::_V1.picMap`. To make it
 safer, there should be `x<size` checks in `GdiV1::decodeV1Gfx()` before
 all three occurrences of writing to `dst[x]`, which would log a warning
 about incorrect encoding and return from the function if `x` is too
 large.)
-- 
Ticket URL: <https://bugs.scummvm.org/ticket/12039>
ScummVM :: Bugs <https://bugs.scummvm.org>
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