The game suddenly crashes within allegro 5 when a picture is being shaded

[hendrikbez]

Is there a way to see what happened when the game crashed

[hendrikbez]

This is all dump I could found
headoverheels.exe.zip

[dougmencken]

it crashed at allegro-5.2.dll+0x48B5

Is there a way to see what happened when the game crashed

yeah, try to run the game via the GNU debugger, gdb

gdb /hoh/bin/headoverheels.exe

then type run there at the gdb prompt

when a crash happens, at the same prompt type bt to get a backtrace

if that's something after getPixel then this is a known issue with allegro 5 and possible over-locking of pictures when they are being shaded

[hendrikbez]

Did play with debugger and did get this from it

Thread 1 "headoverheels" received signal SIGSEGV, Segmentation fault.
0x00007ffaebd548b5 in ?? () from /c/hoh/bin/allegro-5.2.dll
(gdb) vt
Undefined command: "vt".  Try "help".
(gdb) bt
#0  0x00007ffaebd548b5 in ?? () from /c/hoh/bin/allegro-5.2.dll
#1  0x0000000100404a66 in allegro::Pict::getPixelAt (this=<optimized out>, x=x@entry=24,
    y=y@entry=15) at WrappersAllegro.cpp:301
#2  0x000000010043b392 in Picture::getPixelAt (y=<optimized out>, x=24, this=0x7ffffc330)
    at /home/User-Pc/headoverheels-git/source/Picture.hpp:50
#3  ShadowCaster::castShadowOnFloor (tile=..., x=x@entry=89, y=y@entry=447, shadow=...,
    shading=shading@entry=128, transparency=transparency@entry=0 '\000') at ShadowCaster.cpp:347
#4  0x0000000100440243 in Mediator::castShadowOnFloor (this=0xa00210000, floorTile=...)
    at Mediator.cpp:403
#5  0x000000010044abd4 in Room::draw (this=0xa0020df80) at Room.cpp:1282
#6  0x0000000100449c5e in Drawable::drawOn (where=..., this=0xa0020df80)
    at /home/User-Pc/headoverheels-git/source/Drawable.hpp:32
#7  Drawable::drawOn (where=..., this=0xa0020df80)
    at /home/User-Pc/headoverheels-git/source/Drawable.hpp:25
#8  Room::drawRoom (this=0xa0020df80) at Room.cpp:1260
#9  0x000000010047c041 in Isomot::updateMe (
    this=this@entry=0x100518a90 <GameManager::instance+240>) at Isomot.cpp:201
#10 0x00000001004674c6 in GameManager::update (this=0x1005189a0 <GameManager::instance>)
    at GameManager.cpp:155
#11 0x000000010046796e in GameManager::begin (this=<optimized out>) at GameManager.cpp:119
#12 0x00000001004c7bc5 in gui::ContinueGame::act (this=0xa00125d00)
    at guiactions/ContinueGame.cpp:35
#13 0x00000001004b5c35 in gui::Action::doIt (this=0xa00125d00) at guiactions/Action.hpp:34
#14 gui::Label::handleKey (this=<optimized out>, key=...) at gui/Label.cpp:62
#15 0x00000001004b2d97 in gui::GuiManager::begin (this=0xa00036df0) at gui/GuiManager.cpp:124
#16 0x00000001004f0844 in main (argc=<optimized out>, argv=<optimized out>) at main.cpp:213
(gdb)

[dougmencken]

Picture::getPixelAt at Picture.hpp:50

ShadowCaster::castShadowOnFloor at ShadowCaster.cpp:347

exactly where I expected 😏😤

currently you can toggle drawing the shadows off in the menus : options –> adjust graphics –> draw shadows

[dougmencken]

at first I will make three two functions lockReadOnly(), lockWriteOnly(), lockReadWrite() out of that single lock(bool, bool)
reading more throughly what allegro 5 docs say about al_lock_bitmap

then I’ll try to get rid of the line

HeadOverHeels/source/ShadowCaster.cpp

Line 347 in 3ed956a

AllegroColor resultColor = shadyTile.getPixelAt( tilePixel, tileRow );

together with resultColor.equalsRGB( tileColor ) there on

HeadOverHeels/source/ShadowCaster.cpp

Line 352 in 3ed956a

if ( ! shadowColor.isKeyColor() && ! tileColor.isKeyColor() && resultColor.equalsRGB( tileColor ) )

[dougmencken]

@hendrikbez can you please test the current master for having zero segfaults when shadows are on ?

[hendrikbez]

Will test it today, was busy with other things yesterday

[hendrikbez]

Tested it and it does not crash on shadows anymore.

[dougmencken]

Tested it and it does not crash on shadows anymore.

Excellent. Such sudden crashes are very frustrating. I’m closing this