hgr: par: sier

graphics/hgr/parallax/par.s

@@ -163,22 +163,25 @@ skip_color_medium:
 	;===========================
 	; SMALL
 
-	txa
+	txa								; 2
 
-	sec			; subtract frame from YY
+	sec			; subtract frame from YY		; 2
 frame4_smc:
-	sbc	#0
+	sbc	#0							; 2
 
-	eor	X2
-	and	#$10
+	eor	X2							; 3
+	and	#$10							; 2
 
-	beq	skip_color_small
-	lda	#$aa
+	beq	skip_color_small					; 2/3
+	lda	#$aa							; 2
 
-	bne	draw_color
+	bne	draw_color						; 2/3
 skip_color_small:
 
-	lda	#$00
+
+	; fallthrough is black
+
+	lda	#$00							; 2
 
 
 	;========================
@@ -186,20 +189,19 @@ skip_color_small:
 
 draw_color:
 out_smc:
-	sta	$2000,Y
+	sta	$2000,Y							; 5
 
+	dey								; 2
+	cpy	#10							; 2
+	bne	xloop							; 2/3
 
-	dey					; 1
-	cpy	#10
-	bne	xloop				; 2
-
-	dex					; 1
+	dex								; 2
 
 ;	cpx	#$FF
 
-	bpl	yloop				; 2
+	bpl	yloop							; 2/3
 
-	bmi	parallax_forever		; 2
+	bmi	parallax_forever					; 2/3
 
 
 ; for bot

graphics/hgr/parallax/sier.s

@@ -0,0 +1,177 @@
+; Parallax HGR
+
+; by deater (Vince Weaver) <vince@deater.net>
+
+
+; Zero Page
+GBASL           = $26
+GBASH           = $27
+H2              = $2C
+COLOR           = $30
+
+HGR_X           = $E0
+HGR_Y           = $E2
+HGR_COLOR       = $E4
+HGR_HORIZ       = $E5
+HGR_PAGE        = $E6
+
+FRAME		= $F0
+FRAME2		= $F1
+FRAME4		= $F2
+
+X2              = $FB
+COLORS          = $FC
+
+; Soft Switches
+PAGE1   = $C054 ; Page1
+PAGE2   = $C055 ; Page2
+
+
+; ROM routines
+
+HGR     = $F3E2
+HGR2    = $F3D8
+HCLR    = $F3F2
+HPLOT0  = $F457                 ;; plot at (Y,X), (A)
+WAIT    = $FCA8                 ;; delay 1/2(26+27A+5A^2) us
+HPOSN          = $F411         ; (Y,X),(A)  (values stores in HGRX,XH,Y)
+
+
+hgr_lookup_h    =       $1000
+hgr_lookup_l    =       $1100
+div4_lookup	=	$1200
+
+parallax:
+
+	;===================
+	; init screen
+	jsr	HGR
+	jsr	HGR2
+
+	;===================
+        ; int tables
+
+        ldx     #191
+init_loop:
+        txa
+        pha
+        jsr     HPOSN
+        pla
+        tax
+        lda     GBASL
+        sta     hgr_lookup_l,X
+        lda     GBASH
+	and	#$1F				; 20 30    001X 40 50  010X
+        sta     hgr_lookup_h,X
+
+	txa
+	asl
+	asl
+	sta	div4_lookup,X
+
+        dex
+        cpx     #$ff
+        bne     init_loop
+
+
+parallax_forever:
+
+	inc	FRAME							; 5
+
+	;========================
+	; flip page
+
+	lda	HGR_PAGE                ; $40 or $20
+
+	eor	#$60                    ; flip draw_page
+	sta	HGR_PAGE
+
+	asl
+	asl
+	rol
+	eor	#$1
+	tay
+	lda     PAGE1,Y
+
+
+        ldx     #127                    ; init Y
+
+yloop:
+
+	;==============
+	; point output to current line
+
+	lda     hgr_lookup_l,X
+        sta     out_smc+1
+        lda     hgr_lookup_h,X
+	ora	HGR_PAGE
+        sta     out_smc+2
+
+	;==============
+	; current column (work backwards)
+
+	ldy	#39						; 2
+xloop:
+
+;	lda	div4_lookup,Y					; 4+
+;	sta	X2						; 3
+
+	;===========================
+	; LARGE
+
+	txa							; 2
+
+; carry always clear here?
+;	sec			; subtract frame from Y
+	sbc	FRAME						; 3
+
+	eor	div4_lookup,Y					; 4+
+	and	#$40						; 2
+
+	beq	skip_color_large				; 2/3
+	lda	#$ff						; 2
+	bne	draw_color					; 2/3
+skip_color_large:
+
+	;===========================
+	; MEDIUM
+
+	txa							; 2
+
+	sec			; subtract frame from Y		; 2
+
+	adc	FRAME		; go other way			; 3
+
+	and	div4_lookup,Y	; sierpinski			; 4+
+
+	bne	skip_color_medium
+	lda	#$55
+	bne	draw_color
+skip_color_medium:
+
+	; fallthrough is black
+
+	lda	#$00							; 2
+
+
+	;========================
+	; actually draw color
+
+draw_color:
+out_smc:
+	sta	$2000,Y							; 5
+
+	dey								; 2
+	bpl	xloop							; 2/3
+
+	dex								; 2
+
+	bpl	yloop							; 2/3
+
+	bmi	parallax_forever					; 2/3
+
+
+; for bot
+	; $3F5 - 127 + 3  = $379
+
+;	jmp	parallax