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+--- Thread: Disable raster callback? (/showthread.php?tid=485)
Disable raster callback? - mycats - 02-09-2020
I have set raster callback function in the first part of game, and I don't need it in the second part. How to disable it? Setting it to NULL causes rendering errors.
RE: Disable raster callback? - megamarc - 02-09-2020
Passing NULL to TLN_SetRasterCallback() is the way to disable raster effects.
Exactly what kind of "rendering errors" are you experiencing? Can you post some example?
RE: Disable raster callback? - mycats - 02-09-2020
Using DisableBGColor() after disabling raster callback caused errors like this, using SetBGColor(0,0,0) instead fixed problem.
RE: Disable raster callback? - megamarc - 02-09-2020
I'm glad you found the cause so quickly!
In Tilengine you must specify a base background: either a solid color with TLN_SetBGColor() or a fixed bitmap with TLN_SetBGBitmap(). If not, pixels that are not covered by any background layer aren't cleared between frames, leaving the trace you see in the picture. This is not a bug, it's by design, to avoid unnecesary overdraw when you use a background layer that you know that it hasn't transparent pixels, so a base background is not needed.
This is unrelated to raster effects.