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21 lines
841 B
Plaintext
21 lines
841 B
Plaintext
Re: ST XZIP, Color and Mouse, addendum to spec
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Date: 5/26/87
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The color function in the XZIP spec lists eight colors. The Atari
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ST, in 80-column mode, can display at most four of them at any one time.
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They are identified internally by color index numbers 0-3.
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There are two additional restrictions:
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() Only one background color is allowed, which is always index 0.
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(This is a limitation of the software support, not the hardware.)
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This effectively leaves three foreground colors.
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() The mouse pointer uses index 1. Index 1 should always be
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different from index 0 for this reason, or the pointer will be visible
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only as an odd silhouette.
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The current ST XZIP implementation will recycle indices to satisfy
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requests for new colors, using a cheap LRU method. Index 1 will always
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be used to satisfy the first request.
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