summaryrefslogtreecommitdiff
path: root/engine/sine.asm
diff options
context:
space:
mode:
authorBryan Bishop <kanzure@gmail.com>2013-09-08 11:18:39 -0500
committerBryan Bishop <kanzure@gmail.com>2013-09-08 11:18:39 -0500
commit5c4dc08ee451f699471ce69fc8f98265bc80939d (patch)
tree33223a7ef5c01b7fbf4a3a3a176c65b237d5e5ab /engine/sine.asm
parentd4aa6edfa744a45cc82b20cd813462af870b6fef (diff)
parent740f91370db08d2e30c16f34be83c6d14e7d1c60 (diff)
Merge branch 'master' into refactor-preprocessor
Diffstat (limited to 'engine/sine.asm')
-rw-r--r--engine/sine.asm22
1 files changed, 22 insertions, 0 deletions
diff --git a/engine/sine.asm b/engine/sine.asm
new file mode 100644
index 000000000..09d06ca89
--- /dev/null
+++ b/engine/sine.asm
@@ -0,0 +1,22 @@
+Cosine: ; 1b0f
+; Return d * cos(a) in hl
+ add $10 ; 90 degrees
+
+Sine: ; 1b11
+; Return d * sin(a) in hl
+; a is a signed 6-bit value.
+
+ ld e, a
+
+ ld a, [hROMBank]
+ push af
+ ld a, BANK(_Sine)
+ rst Bankswitch
+
+ call _Sine
+
+ pop af
+ rst Bankswitch
+ ret
+; 1b1e
+