FS#4736 - hidden sprites drawn transiently

Attached to Project: OpenTTD
Opened by Ingo von Borstel (planetmaker) - Friday, 19 August 2011, 07:05 GMT
Last edited by frosch (frosch) - Saturday, 20 August 2011, 08:47 GMT
Type Bug
Category NewGRF
Status Closed
Assigned To No-one
Operating System All
Severity Low
Priority Normal
Reported Version trunk
Due in Version Undecided
Due Date Undecided
Percent Complete 100%
Votes 0
Private No


See the attached savegame, best in fast-forward The farm near 'here' has tiles where the fences are all hidden according to temporary storage variables. Still they transiently flicker into being somewhat periodically.

Possibly it's an interference with an industry processed previously which has fences drawn as the glitch doesn't seem to happen with all industries of the same kind. Decision on drawing fences is made via temporary registers.
This task depends upon

Closed by  frosch (frosch)
Saturday, 20 August 2011, 08:47 GMT
Reason for closing:  Bug in NewGRF
Additional comments about closing:  usage of unintialised temporary storage
Comment by frosch (frosch) - Saturday, 20 August 2011, 08:47 GMT
Taking the output from grf2html:
Industry tile 0xBE starts at action 3 sprite # 2957.
When following the action2 chain it always ends up at a big advvaract, which in the very first instruction reads temporary register 00.
The value of this register is undefined.