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https://github.com/uffejakobsen/acme.git
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60 lines
2.3 KiB
Plaintext
60 lines
2.3 KiB
Plaintext
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Hi!
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This is a preliminary release of ACME. I added basic support for
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floating point maths. Consider this a special version for beta
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testers. Known bugs: Segment counting may be screwed up at the moment.
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New:
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The maths parser knows about floating point maths, so you can finally
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build sin/cos tables directly in ACME. But the expression parser still
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uses integer calculations per default. Here are the rules:
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a) if a maths operation is useless when done with integers, it is done
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with floats and returns a float. Applies to sin(), cos(), tan(),
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arcsin(), arccos(), arctan() and float(): These are always computed in
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float mode and always return floats.
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b) if a maths operation is useles when done with floats, it is done
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with integers and returns an integer. Applies to NOT, AND, OR, XOR,
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MOD, DIV, LSR, lowbyteof, highbyteof, bankbyteof and int(). These are
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always computed in integer mode and always return integers.
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c) All other mathematical operations are done in float mode if and
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only if at least one of the operands is a float. So "1/2*2" will give
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zero because it is done in integer mode, but "1.0/2*2" will give 1
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because it is done in float mode.
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To force a numerical value to be flagged as being a float, just add
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a decimal point and a zero. If a decimal value ends with a
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dot character, ACME switches to using the C type "double" and keeps
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reading digits. The value is then flagged internally as being float.
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Examples:
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!byte 1 / 2 * 2 ; gives 0 (integer maths)
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!byte 1 / 2 * 2.0 ; gives 0 (1/2 => 0 in integer maths,
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; float usage comes too late)
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!byte 1 / 2.0 * 2 ; gives 1 (FP in effect)
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!byte 1 / 2.0 * 2.0 ; gives 1 (FP in effect)
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!byte 1.0 / 2 * 2 ; gives 1 (FP in effect)
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!byte 1.0 / 2 * 2.0 ; gives 1 (FP in effect)
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!byte 1.0 / 2.0 * 2 ; gives 1 (FP in effect)
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!byte 1.0 / 2.0 * 2.0 ; gives 1 (FP in effect)
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You can use the new float() and int() functions to ensure the type of
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maths:
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!byte a / b * c ; depends on a/b/c's internal flags
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!byte float(a)/b*c ; calculation is done in FP
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!byte int(a)/int(b)*int(c); calculation is done in integer
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As you will have guessed, the trigonometric functions assume radians
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for measuring angles (90 degrees equals PI/2).
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Have a look at the example source code, it builds some sin/cos tables.
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Have fun, and let me know what you think,
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Marco Baye
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