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Operating System Specific Discussions => Amiga OS => Amiga OS -- Development => Topic started by: hextreme on May 19, 2007, 08:45:53 AM

Title: fast display of blitter objects (bobs)
Post by: hextreme on May 19, 2007, 08:45:53 AM
Hello!
I have problem with Bobs (blitter objects). They are displayed too slow. How to speed'em up? For example how to create environment like in Benefactor under WHDLoad, which saves old View, shut downs system until F10 is pressed and there are even many objects drawn by Blitter without lags.
I don't have graphic card so it's under AGA chipset.
Thanks in advance for response! If you wish sample code just ask.
Title: Re: fast display of blitter objects (bobs)
Post by: SamuraiCrow on May 19, 2007, 08:19:54 PM
The reason the bobs are too slow is a shortcoming in the speed of the AGA chipset.  There are some patches like the Games Master System (http://aminet.net/dev/misc/gms_dev.lha) that will do CPU-assisted blitting to shore up the problem but this is only a kludge.  I'm afraid the best solution is to write software with graphics cards in mind.  (Or use vsprites instead of bobs.)
Title: Re: fast display of blitter objects (bobs)
Post by: Cass on May 19, 2007, 10:27:41 PM
In AMOS you could switch off the multitasking by POKing the exec library, and activating AMAL routines.
Also synchronising with the VBlank, you get a smoother effect.
Title: Re: fast display of blitter objects (bobs)
Post by: hextreme on May 20, 2007, 07:25:50 AM
Thanks for response! I finally found the solution - I am disabling all interrupts by banging hardware and writing value 0x7FFF into custom.intena and bobs run very fast. :-)
Title: Re: fast display of blitter objects (bobs)
Post by: Karlos on May 20, 2007, 01:23:10 PM
Quote

hextreme wrote:
Thanks for response! I finally found the solution - I am disabling all interrupts by banging hardware and writing value 0x7FFF into custom.intena and bobs run very fast. :-)


Just make sure you re-enable the relevant ones when you want to do any I/O ;-)