I'm learning more about memory stuff with the pico-8 and it's super interesting!
I had one quick question for zep.
What is meant in the documentation by this line?
"0x5f00 draw state [,cart data] (1024 bytes incl. unused)"
What exactly is draw state?
How is the data interpreted/formatted?
What does [,cart data] mean?
What is meant by (1024 bytes incl. unused)?
Every part of this is so cryptic to me, please help!
The draw state is all of the data that drawing functions (line(), spr() etc) operate on. They're undocumented because they might change, but here they are (use at own risk!):
0x5f00+ 0..0xf draw palette 0x10..0x1f screen palette 0x20..0x23 clip coordinate left, right, top, bottom 0x24 unused 0x25 current draw colour 0x26 cursor x 0x27 cursor y 0x28..0x2b camera position x,y (small endian int16s) 0x2c screen mode // 0 128x128 (normal) 1 64x128 2 128x64 3 64x64
0x5fc0..0x5fff will possible be for permanent data storage in future, maybe
this is what's meant by cart data
incl. unused means the data size (256 bytes) includes a bunch of unused addresses -- not every byte means something.
You can probably count on the first 128 bytes being used for draw state in future though. So if you need to backup and then restore all the clipping and palette settings etc for some reason, you can do something like memcpy(0x5e80, 0x5f00, 128) to backup and memcpy(0x5f00, 0x5e80, 128) to restore.
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