Use fixed-point DIV function for a generalized sine_wave table macro

2018-02-03 13:26:34 -05:00
parent d11cac9e83
commit b0d84c64a6
2 changed files with 5 additions and 4 deletions
--- a/macros/data.asm
+++ b/macros/data.asm
@@ -112,10 +112,11 @@ ENDM


 sine_wave: MACRO
-x = 0.0
+; \1 samples of sin(x) from x=0 to x<32768 (pi radians)
+x = 0
 rept \1
 	dw (sin(x) + (sin(x) & $ff)) >> 8 ; round up
-x = x + 1024.0 ; a circle has 65536.0 "degrees"
+x = x + DIV(32768, \1) ; a circle has 65536 "degrees"
 endr
 ENDM