lovebyte: work on rainbowsquares

demos/lovebyte2024/rainbow_squares_128/rainbow_squares.s

@@ -23,8 +23,7 @@ XX_TL	=	$F9
 ;YY	=	$FA
 YY_TH	=	$FB
 YY_TL	=	$FC
-;T_L	=	$FD
-;T_H	=	$FE
+FRAME	=	$FD
 SAVED	=	$FF
 
 ; Soft switches
@@ -40,21 +39,24 @@ HPLOT0  = $F457
 PLOT1	= $F80E		;; PLOT at (GBASL),Y (need MASK to be $0f or $f0)
 GBASCALC= $F847		;; take Y-coord/2 in A, put address in GBASL/H ( a trashed, C clear)
 SETGR   = $FB40
+WAIT    = $FCA8                 ; delay 1/2(26+27A+5A^2) us
 
 	;================================
 	; Clear screen and setup graphics
 	;================================
-sier:
-	jsr	HGR2		; set FULLGR, sets A=0
+rainbow_squares:
+	jsr	HGR		; set FULLGR, sets A=0,Y=0
+	sta	FRAME		; init frame
 
-sier_outer:
+rainbow_outer:
+	; Y=0 from both paths
 
-	ldy	#0		; YY starts at 0
+;	ldy	#0		; YY starts at 0
 
 	sty	YY_TL
 	sty	YY_TH
 
-sier_yloop:
+rainbow_yloop:
 
 	; calc YY_T (8.8 fixed point add)
 	; save space by skipping clc as it's only a slight variation w/o
@@ -66,36 +68,13 @@ sier_yloop:
 	adc	T_H
 	sta	YY_TH
 
-;	txa	; YY			; plot call needs Y/2
-;	lsr
-
-;	php
-
-;	bcc	even_mask
-;	ldy	#$f0
-;	.byte	$2C	; bit hack
-;even_mask:
-;	ldy	#$0f
-;	sty	MASK
-
-;	jsr	GBASCALC	; take Y-coord/2 in A, put address in GBASL/H ( a trashed, C clear)
-
-;	lda	GBASH
-;draw_page_smc:
-;	adc	#0
-;	sta	GBASH		 ; adjust for PAGE1/PAGE2 ($400/$800)
-
-;	plp
-;	jsr	$f806		; trick to calculate MASK by jumping
-				; into middle of PLOT routine
-
 	; reset XX to 0
 
 	ldx	#0		; XX
 	stx	XX_TL
 	stx	XX_TH
 
-sier_xloop:
+rainbow_xloop:
 
 	; want (YY-(XX*T)) & (XX+(YY*T)
 
@@ -130,6 +109,7 @@ sier_xloop:
 
 	beq	white
 black:
+	bit	$C030
 	lda	#00	; black
 	.byte	$2C	; bit trick
 white:
@@ -153,39 +133,51 @@ white:
 
 	inx		; XX
 	cpx	#255
-	bne	sier_xloop
+	bne	rainbow_xloop
 
 	iny		; YY
 	cpy	#192
-	bne	sier_yloop
+	bne	rainbow_yloop
 
 	; inc T
+	inc	T_L
+
 ;	clc
-	lda	T_L
-blah_smc:
-	adc	#1
-	sta	T_L
-	bcc	no_carry
-	inc	T_H
-no_carry:
+;	lda	T_L
+;blah_smc:
+;	adc	#1
+;	sta	T_L
+;	bcc	no_carry
+;	inc	T_H
+;no_carry:
 
-	; speed up the zoom as it goes
-;	inc	blah_smc+1
+	; done frame
 
 
-	; x is 48
-;flip_pages:
-;	lda	draw_page_smc+1 ; DRAW_PAGE
-;	beq	done_page
-;	inx
-;done_page:
-	; X=48 ($30)	PAGE1=$C054-$30=$C024
-;	ldy	$C024,X		; set display page to PAGE1 or PAGE2
 
-;	eor	#$4             ; flip draw page between $400/$800
-;	sta	draw_page_smc+1 ; DRAW_PAGE
+	inc	FRAME
+	lda	FRAME
+	cmp	#2
+	beq	really_done
 
-	jmp	sier_outer	; what can we branch on?
+	jsr	HGR2
+	; A/Y=0
+
+	jmp	rainbow_outer	; what can we branch on?
+
+really_done:
+
+	lda	#200
+	jsr	WAIT
+
+	bit	PAGE1
+
+	lda	#200
+	jsr	WAIT
+
+	bit	PAGE2
+
+	jmp	really_done