Quote:
Originally Posted by daxb
Now I'm confused. I don't understand the limitation of max 256 pens on Amiga screen when using RTG. Where does the limit come from?
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A pen is a color register in the Amiga graphics chipset. AGA has 256 color registers which can hold 24 bit RGB values, and OCS/ECS have only 16 color registers which can store 12 bit RGB and there is an EHB flag somewhere. Using the chipset means maximal 256 colors out of 16 million for AGA or 16 (32 with EHB) colors out of 4096 for OCS/ECS.
On a gfx card you can access the 15/16/24 bit RGB values (+alpha channel byte?) of every pixel directly with Read/WritePixelArray() if your software allows that.
@Michael
Releasing pens is only possible on WB screens as long as DOpus5 has not been started. If DOpus shares the same screen with WB it will always push up the pen reference counters only so that not even WB can reduce these shared counters to zero again in order to set the pens free.
Whenever a Guru can't be displayed anymore by the system it stores the Guru number in address $100 and writes "Help" into address $0. After a reboot it grabs the Guru number from $100 then and displays it. Maybe MCP's Guru history patch tries to get this information, too, but reading from $0 or $100 throws Enforcer hits as I've just learned a week ago.
