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pt3: really finish calculate_note() this time

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This commit is contained in:
Vince Weaver 2019-05-12 21:30:01 -04:00
parent 4e51fe3e57
commit 8d78918335
1 changed files with 62 additions and 21 deletions
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83
pt3_player/pt3_lib.s
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@ -400,9 +400,12 @@ pt3_init_song:
rts
e_slide_amount: .byte $0
;=====================================
; Calculate Note
;=====================================
;
calculate_note:
lda note_a+NOTE_ENABLED
@ -638,28 +641,66 @@ done_clamp_amplitude:
envelope_slide:
; /* Envelope slide */
; /* If b1 top bits are 10 or 11 */
; if ((b1 & 0x80) != 0) {
; if ((b0 & 0x20) != 0) {
; j = ((b0>>1)|0xF0) + a->envelope_sliding;
; }
; else {
; j = ((b0>>1)&0xF) + a->envelope_sliding;
; }
; if (( b1 & 0x20) != 0) {
; a->envelope_sliding = j;
; }
; pt3->envelope_add+=j;
; }
; /* Noise slide */
; else {
; pt3->noise_add = (b0>>1) + a->noise_sliding;
; if ((b1 & 0x20) != 0) {
; a->noise_sliding = pt3->noise_add;
; }
; }
; Envelope slide
; If b1 top bits are 10 or 11
lda #$80
bit sample_b1
beq noise_slide ; if ((b1 & 0x80) != 0) {
lda #$20
bit sample_b0
beq envelope_slide_down ; if ((b0 & 0x20) != 0) {
; FIXME: this can be optimized
envelope_slide_up:
lda sample_b0
lsr
ora #$f0
clc
adc note_a+NOTE_ENVELOPE_SLIDING
sta e_slide_amount ; j = ((b0>>1)|0xF0) + a->envelope_sliding
jmp envelope_slide_done
envelope_slide_down:
lda sample_b0
lsr
and #$0f
clc
adc note_a+NOTE_ENVELOPE_SLIDING
sta e_slide_amount ; j = ((b0>>1)&0xF) + a->envelope_sliding;
envelope_slide_done:
lda #$20
bit sample_b1
beq last_envelope ; if (( b1 & 0x20) != 0) {
lda e_slide_amount
sta note_a+NOTE_ENVELOPE_SLIDING ; a->envelope_sliding = j;
last_envelope:
clc
lda e_slide_amount
adc pt3_envelope_add
sta pt3_envelope_add ; pt3->envelope_add+=j;
noise_slide:
; Noise slide
; else {
lda sample_b0
lsr
clc
adc note_a+NOTE_NOISE_SLIDING
sta pt3_noise_add ; pt3->noise_add = (b0>>1) + a->noise_sliding;
lda #$20
bit sample_b1
beq noise_slide_done ; if ((b1 & 0x20) != 0) {
lda pt3_noise_add
sta note_a+NOTE_NOISE_SLIDING ; noise_sliding = pt3_noise_add
noise_slide_done:
;======================
; set mixer