Yes, this was indeed the case: as mentioned in my previous post, transparent sprite pixels were never rendered into sprite buffer (since they have zero effect in "normal" mode, no matter the value of priority and palette bits). Modifying the pixel priority lookup table calculation and the sprite pixel rendering macro fixed this effect and a few others at the end of the demo.Kabuto wrote:This sounds like you're not treating transparent sprite pixels correctly, this effect uses sprites with palette 3, so their transparent pixels will be written to the linebuffer as 0x30.
Remaining issues so far:
1) a few vertical jittering during the zooming and twisting of overdrive 2 logo (not sure what causes this, maybe mid-line vscroll modifications in 2-cell vscrolling mode ?)
2) missing broken border tricks during the arcade scene + some rolling black lines over this screen likely caused by the missing HINT occurences during vblank (this one will need some work since it's not so easy to dynamically increase the height of the rendered frame in emulation loop)
3) rotating textured cubes scene is completely broken (this one needs some investigation but probably relies on precisely timed VDP writes among other things)
4) graphical issue during transition between the "incoming" scene and the moving white spotlights (not sure how you call this effect) at around 5:20 in youtube official video (needs investigation as well)
5) some graphical issues during the transition between the 'ninja robot' scene and the plasma effect with locked Titan logo (again not 100% sure but some might be related to mid-line vscroll modifications)