Arpeggio fixed. Several optimizations.

Arpeggio fixed. Several optimizations.

README.md

@@ -58,16 +58,17 @@ instr_test.gb is a sample of the default sounds.
 
 range_test.gb is just a test of what notes the GB can reach (C3 - B8).
 
-arpeggio_test.gb tests arpeggio effects.
+effects_test.gb tests arpeggio and "cut note" effects.
 
 The mod file isn't 100% accurate. Sounds are a bit different from the real ones, so you should make roms and test them in emulators or real GB often.
 
 Changelog
 ---------
 
 - Version 2.1.0 (2014/5/24)
- - Fixed arpeggio effect. Now it keeps looping until tick = 0 (previously it only looped once).
+ - Fixed arpeggio effect. Now it keeps looping until tick = 0 (previously it only looped once). Loops 3 steps, not 4.
  - Added "Cut Note" effect.
+ - Effects optimizations.
 
 - Version 2.0.1 (2014/5/23)
  - Fixed effects in channels 1, 2 and 3 in GBDK version.

gbdk_example/gbt_player.s

@@ -80,6 +80,8 @@ gbt_arpeggio_freq_index::
 	.ds 3*3 ; { base index, base index + x, base index + y } * 3
 gbt_arpeggio_enabled::
 	.ds 3*1 ; if 0, disabled
+gbt_arpeggio_tick::
+	.ds	3*1
 
 ; Cut note
 gbt_cut_note_tick::
@@ -341,6 +343,24 @@ gbt_update:
 .dontexit:
 	ld	(hl),#0x00 ; reset tick counter
 
+	; Clear tick-based effects
+	; ------------------------
+
+	xor	a,a
+	ld	hl,#gbt_arpeggio_enabled ; Disable arpeggio
+	ld	(hl+),a
+	ld	(hl+),a
+	ld	(hl),a
+	dec	a ; a = 0xFF
+	ld	hl,#gbt_cut_note_tick ; Disable cut note
+	ld	(hl+),a
+	ld	(hl+),a
+	ld	(hl+),a
+	ld	(hl),a
+
+	; Update effects
+	; --------------
+
 	ld	a,#0x01
 	ld	(#0x2000),a ; MBC1, MBC3, MBC5 - Set bank 1
 	call	gbt_update_effects_bank1 ; Call update function in bank 1 (in gbt_player_bank1.s)