Welcome back, happy to be writing back after so long. I’ve got myself on the work again and there’s 2-3 days of progress I want to brief about. But before that, I must inform that the initial PR for iBASS support has been merged(it was merged while I was away), which means that now you can play iBASS on the debug builds. All you need to arrange are the game files. Continuing the efforts of porting, I implemented the text chooser(the PR is currently opened). But first let’s understand what exactly is the text chooser.
Text Chooser
See the questions at the top. When we talk to the NPCs, a list of questions in this form appears. We have to select a dialogue from this list.
This is how it works.
The PR is currently opened. Once it gets merged, you’ll be able to use this feature.
The silent killer
Day before yesterday, while I was implementing the text chooser, the game crashed on starting. I was lucky that I had run that time with gdb so I recorded the backtrace-
Thread 1 “scummvm” received signal SIGSEGV, Segmentation fault.
0x000055555924128a in READ_UINT16 (ptr=0x55555ed36000) at ./common/endian.h:209
209 return ((const Unaligned16 *)ptr)->val;
(gdb) bt
#0 0x000055555924128a in READ_UINT16 (ptr=0x55555ed36000)
at ./common/endian.h:209
#1 Sky::Disk::getFileInfo (this=0x55555e4a7640, fileNr=60600)
at engines/sky/disk.cpp:310
#2 0x0000555559240c60 in Sky::Disk::fileExists
(this=0x55555e4a7640, fileNr=60600) at engines/sky/disk.cpp:169
#3 0x000055555922e5c6 in Sky::SkyEngine::init (this=0x55555e48dec0)
at engines/sky/sky.cpp:462
#4 0x000055555922f0f1 in Sky::SkyEngine::run (this=0x55555e48dec0)
at ./engines/sky/sky.h:130
#5 0x00005555560e808c in runGame
(enginePlugin=0x55555d3d2f60, system=…, game=…, meDescriptor=0x0)
at base/main.cpp:328
#6 0x00005555560ea70d in scummvm_main (argc=1, argv=0x7fffffffde28)
at base/main.cpp:840
#7 0x00005555560e4d84 in main (argc=1, argv=0x7fffffffde28)
at backends/platform/sdl/posix/posix-main.cpp:56
the getFileInfo function reads from a variable named _dinnerTableArea that is never written to in iBASS since iBASS doesn’t have a separate sky.dnr file.
So, the game starts successfully most of the time because it contains garbage. If it doesn’t, the game crashes. To fix this, I used the getEntry() method.
That’s all for this blog. See in the next post.
Thanks for reading 🙂