Viewing Issue Advanced Details
ID Category [?] Severity [?] Reproducibility Date Submitted Last Update
02014 Graphics Minor Always Jul 15, 2008, 21:50 Dec 17, 2022, 13:53
Tester Kold666 View Status Public Platform MAME (Official Binary)
Assigned To Resolution Open OS
Status [?] Confirmed Driver
Version 0.126 Fixed in Version Build Normal
Fixed in Git Commit Github Pull Request #
Summary 02014: All sets in aliens.c: Sprite lag
Description In mame there is a lot of sprite lag which the pcb doesn't have.
Steps To Reproduce
Additional Information
Github Commit
Flags Verified with Original
Regression Version
Affected Sets / Systems All sets in aliens.c
Attached Files
 
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Notes
8
User avatar
No.01647
Tafoid
Administrator
Jul 16, 2008, 04:18
I just tried the game and it seemed to look ok and respond ok. Is it possible to record a small movie to show the PCB action so the devs can get a better idea what might be the issue?
User avatar
No.01648
Kold666
Developer
Jul 16, 2008, 04:46
Nicola knows the problem as he asked me to check it. Since there is no sprite lag I decided to post a bug in the case there is no immediate solution.
User avatar
No.11413
abelardator2
Tester
Jan 27, 2015, 10:15
edited on: Jan 27, 2015, 10:34
When we set a "Overclock MainCPU" for example 160%, no there loss of sprites, when overload them sprites on screen.
I uploaded a recording of the actual PCB game.

www.youtube.com/watch?v=F27UuDkzKtw

I have also seen that the set aliensa (Asia), the sprite of player and enemies is completely broken (0.157)
User avatar
No.11418
Haze
Senior Tester
Jan 27, 2015, 13:12
aliens (asia) sprite bug was a silly rom load problem.
User avatar
No.15982
MetalGod
Senior Tester
Jan 2, 2019, 22:46
edited on: Jan 2, 2019, 23:33
Abelardator video here with no need to go to youtube:



Mame full gameplay here:
User avatar
No.20902
Alex7
Tester
Dec 3, 2022, 21:37
another real arcade video
User avatar
No.20954
Haze
Senior Tester
Dec 13, 2022, 18:50
this seems to be somewhat improved with hap's recent changes, however the driving sections still flicker because MAME doesn't give the CPU enough time to prepare the spritelist before drawing the screen with it.

the vblank interrupt is being triggered by the sprite device
TIMER_CALLBACK_MEMBER( k051960_device::scanline_callback )

but the draw frame happens on the same line, meaning sometimes you get an incomplete spritelist, or one partially from a different frame.

the code there can also only cope with 255 scanlines, so if the real frametiming has more that would be an issue.
User avatar
No.20964
hap
Developer
Dec 17, 2022, 13:53
edited on: Dec 17, 2022, 16:47
I guess spriteram could be buffered.

*edit* Furrtek is researching this sprite chip (051960+051937), maybe what he finds out can solve it.