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36 lines
1.5 KiB
Plaintext
36 lines
1.5 KiB
Plaintext
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Lightpen Functions for C02 Programs
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This module contains a constant and function for reading lightpens on
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systems that support them.
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The constants and assembly code vary by system, so when invoking the
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cross-compilers, the command line option -s must be used to ensure that
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the correct header files are included.
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At the beginning of the program use the directives
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#include <lgtpen.h02>
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The following constants are defined:
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#LGTPNS Light pen status. If loght pen support is available,
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this will be 255 (true), otherwise, it will be 0 (false).
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The following function is defined:
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h,v,t = lgtpen(); Returns the state of the lightpen ot lightgun.
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This function returns three values: the first
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is the horizontal position on the screen, the
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second is the vertical position on screen, and
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the third is the state of the button or trigger
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(255 if pressed, otherwise 0).
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Note: The position returned by this function is
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based on the position of the raster beam and does
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not directly correspond to pixel coordinates.
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Therefore, some sort of calibration and conversion
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will be necessary when using a light pen.
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Note: This library has no external dependencies.
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