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Old 23 September 2013, 19:40   #410
commodorejohn
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Join Date: Jun 2012
Location: Duluth, Minnesota (USA)
Age: 32
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Quote:
Originally Posted by dlfrsilver View Post
Each tile is coded on a byte or a word. if it's coded on a byte, the you can have 65535 tiles (64Kb of video memory).

The memory on the amiga is something else. there is no tilesystem, and if you want one it must be programmed. An amiga would require megabytes of RAM to get the equivalent of a tilesystem like the SNES or a coin-op machine.

The tilemap systems never see or access the graphics. The system get the access and display via the Hex code of a said tile in VRAM.
Uh, no. No no no. Tilemaps are arrays of pointers to actual tile definitions that have to be stored in graphics memory. Tiles themselves take up just as much space as Amiga graphics of equivalent resolution and bitdepth, because they're just small bitmaps. If you're using 16-color 8x8 tiles, you can store a maximum of 2048 tiles in 64KB. (And as for word-length tilemap definitions, not all the bits are used for the pointer - there's also palette select and horizontal/vertical flip bits.) There's also the fact that the tilemap itself has to go in video memory, along with the sprite parameter list. (Can't remember whether the palette definitions do, though.) Tilemap hardware isn't magic.

And doing tiled graphics on the Amiga would take up the exact same amount of space for the graphics at equivalent size and bitdepth, plus a screen bitmap for the output (and the code itself would take up some memory and CPU time.) Not "megabytes."
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