second: add in circles effect

demos/hellmood_memories/Makefile

@@ -6,13 +6,13 @@ PNG_TO_40x48D = ../../utils/gr-utils/png_to_40x48d
 PNG2RLE = ../../utils/gr-utils/png2rle
 B2D = ../../utils/bmp2dhr/b2d
 TOKENIZE = ../../utils/asoft_basic-utils/tokenize_asoft
-
+EMPTY = ../../empty_disk/
 
 all:	memories.dsk
 
 memories.dsk:	HELLO CIRCLES.BAS CIRCLES CHECKERS CHECKERS_SMALL PLANE \
 		SIER TUNNEL TNM CIRCLES_NORMAL
-	cp empty.dsk memories.dsk
+	cp $(EMPTY)empty.dsk memories.dsk
 	$(DOS33) -y memories.dsk SAVE A HELLO
 	$(DOS33) -y memories.dsk SAVE A CIRCLES.BAS
 	$(DOS33) -y memories.dsk BSAVE -a 0x070 CIRCLES

demos/second/gr_plot.s

@@ -1,3 +1,9 @@
+
+	; monitor, horizontal=Y	vert=a
+plot_compat:
+	sty	XPOS
+	sta	YPOS
+
 	;================================
 	; plot routine
 	;================================

demos/second/part01_intropan/horiz_scroll.s

@@ -72,7 +72,8 @@ pil_smc2:
 	cpx	#$ff
 	bne	pan_outer_loop
 
-;	jsr	wait_until_keypress
+	lda	KEYPRESS
+	bmi	done_pan
 
 	inc	COUNT
 	lda	COUNT
@@ -80,6 +81,9 @@ pil_smc2:
 
 	bne	pan_outer_outer_loop
 
+done_pan:
+	bit	KEYRESET
+
 	rts
 
 .include "scroll_tables.s"

demos/second/part04_chess_shapes/Makefile

@@ -18,6 +18,7 @@ chess.o:	chess.s \
 	../zx02_optim.s \
 	../hgr_copy_fast.s \
 	interference.s \
+	circles.s \
 	../zp.inc ../hardware.inc ../qload.inc \
 	graphics/chess_object2.hgr.zx02
 	ca65 -o chess.o chess.s -l chess.lst

demos/second/part04_chess_shapes/chess.s

@@ -263,6 +263,18 @@ tunnel_loop:
 main_tunnel_done:
 	bit	KEYRESET
 
+	;==================
+	;==================
+	;==================
+	; DO circles HERE
+	;==================
+	;==================
+	;==================
+
+	jsr	zooming_circles
+
+	; todo, fade to white
+
 	;==================
 	;==================
 	;==================
@@ -271,6 +283,7 @@ main_tunnel_done:
 	;==================
 	;==================
 
+
 	jsr	interference
 
 
@@ -289,6 +302,7 @@ main_interference_done:
 	.include	"../hgr_sprite_big.s"
 
 	.include	"interference.s"
+	.include	"circles.s"
 	.include	"../hgr_page_flip.s"
 
 	; wait A * 1/50s

demos/second/part04_chess_shapes/circles.s

@@ -0,0 +1,106 @@
+; Zooming Circles, based on the code in Hellmood's Memories
+
+; by deater (Vince Weaver) <vince@deater.net>
+
+; 103 bytes
+
+;.globalzp squares_table_y
+;.globalzp color_lookup
+;.globalzp smc1,smc2,smc3,smc4
+
+
+zooming_circles:
+
+	;===================
+	; init screen
+	bit	LORES
+	bit	FULLGR
+	bit	PAGE1
+	lda	#0
+	sta	DRAW_PAGE
+						; 3
+						;====
+						; 6
+circle_forever:
+
+	inc	FRAME				; 2
+
+	ldx	#24				; 2
+	stx	Y2				; 2
+	dex					; 1
+
+yloop:
+	ldy	#20				; 2
+	sty	X2				; 2
+	dey					; 1
+
+xloop:
+
+	clc					; 1
+	lda	squares_table_y+4,y		; 3
+	asl					; 1
+	asl					; 1
+	adc	squares_table_y,x		; 2
+
+	lsr					; 1
+	adc	FRAME				; 2
+	and	#$1f				; 2
+
+; and	#$18
+; 00, 10 = black
+; 01  = grey 55 or aa
+; 11  = light blue 77
+
+	lsr					; 1
+	lsr					; 1
+	lsr					; 1
+	sty	TEMPY				; 2
+	tay					; 1
+	lda	color_lookup,Y			; 3
+	sta	COLOR				; 2
+
+	ldy	X2	; Y==X2			; 2
+	txa		; A==Y1			; 1
+	jsr	plot_compat	; (X2,Y1)		; 3
+	lda	Y2	; A==Y2			; 2
+	jsr	plot_compat	; (X2,Y2)		; 3
+
+	ldy	TEMPY	; Y==X1			; 2
+	txa		; A==Y1			; 1
+	jsr	plot_compat	; (X1,Y1)		; 3
+	lda	Y2	; A==Y2			; 2
+	jsr	plot_compat	; (X1,Y2)		; 3
+
+	inc	X2				; 2
+
+	dey					; 1
+	bpl	xloop				; 2
+
+	inc	Y2				; 2
+
+	dex					; 1
+	bpl	yloop				; 2
+
+	lda	KEYPRESS
+	bmi	done_circles
+
+	bpl	circle_forever		; bra
+
+done_circles:
+	bit	KEYRESET
+	rts
+
+
+
+; 24 bytes
+squares_table_y:
+.byte $24,$21,$1e,$1b,$19,$16,$14,$12
+.byte $10,$0e,$0c,$0a,$09,$07,$06,$05
+.byte $04,$03,$02,$01,$01,$00,$00
+
+color_lookup:
+.byte	$00		; also last byte of squares table
+.byte	$55,$00,$77
+
+.include "../gr_plot.s"
+.include "../gr_offsets.s"

demos/second/part04_chess_shapes/interference.s

@@ -39,13 +39,13 @@ plot_setup:
 	lsr			; shift bottom bit into carry		; 2
 	tay
 
-	bcc	plot_even						; 2nt/3
-plot_odd:
+	bcc	do_plot_even						; 2nt/3
+do_plot_odd:
 	lda	#$f0							; 2
-	bcs	plot_c_done						; 2nt/3
-plot_even:
+	bcs	do_plot_c_done						; 2nt/3
+do_plot_even:
 	lda	#$0f							; 2
-plot_c_done:
+do_plot_c_done:
 	sta	mask_smc2+1						;
 	eor	#$FF							; 2
 	sta	mask_invert_smc1+1					;