d2_hgr: add code to quit when key pressed

then optimized to find room for it

demos/d2/d2.s

@@ -1,8 +1,10 @@
 ; HGR Demo2
 
-; by deater (Vince Weaver) <vince@deater.net>
+; Apple II graphics/music in 1k
 
-; 1484
+; 1k demo for Demosplash 2021
+
+; by deater (Vince Weaver) <vince@deater.net>
 
 ; Zero Page
 	.include "zp.inc"
@@ -117,11 +119,15 @@ forever:
 
 .include "moving.s"
 
-	;=====================
-	; clear screen
+	;=========================
+	; clear screen first time
+
+skip_clear_smc:
+	lda	#0
+	bne	skip_clear
 
 	jsr	fast_hclr
-
+skip_clear:
 	jsr	flip_page
 
 	;=====================
@@ -145,6 +151,7 @@ forever:
 
 	lda	#$7f
 	sta	color_smc+1
+	sta	skip_clear_smc+1
 	lda	#159
 	sta	moving_size_smc+1
 	sta	oval_size_smc+1
@@ -163,6 +170,9 @@ forever:
 	; common flip page routine
 
 flip_page:
+	lda	KEYPRESS
+	bmi	its_over
+
 	ldy	#$0
         lda     HGR_PAGE        ; will be $20/$40
         cmp     #$20
@@ -176,7 +186,18 @@ done_flip_page:
 
         rts
 
+	;================
+	; halt music
+	; stop playing
+	; turn off sound
+its_over:
+	sei
+	lda	#$3f
+	ldx	#7
+	jsr	ay3_write_reg
 
+stuck_forever:
+	bne	stuck_forever
 
 
 ;      01234567890123456789012345678901234567890"
@@ -222,6 +243,8 @@ sinetable_base:
 
 sinetable=$8000
 
+.include	"fast_hclr.s"
+
 ; music
 .include	"mA2E_2.s"
 .include        "interrupt_handler.s"

demos/d2/dsr_shape.s

@@ -58,25 +58,6 @@ long_wait:
 	dex
 	bne	long_wait
 
-	rts
-
-fast_hclr:
-	lda	HGR_PAGE
-	sta	hclr_smc+2
-	ldy	#0
-hclr_outer:
-	tya
-hclr_inner:
-hclr_smc:
-	sta	$2000,Y
-	iny
-	bne	hclr_inner
-
-	inc	hclr_smc+2
-	lda	hclr_smc+2
-	and	#$1f
-	bne	hclr_outer
-
 ;	rts
 
 ;shape_dsr:

demos/d2/fast_hclr.s

@@ -0,0 +1,18 @@
+fast_hclr:
+	lda	HGR_PAGE
+	sta	hclr_smc+2
+	ldy	#0
+hclr_outer:
+	tya
+hclr_inner:
+hclr_smc:
+	sta	$2000,Y
+	iny
+	bne	hclr_inner
+
+	inc	hclr_smc+2
+	lda	hclr_smc+2
+	and	#$1f
+	bne	hclr_outer
+
+	rts

demos/d2/hello.bas

@@ -1,2 +1,6 @@
 5 HOME
-10 PRINT CHR$(4);"CATALOG"
+10 PRINT "HGR DEMO2 - 1K DEMO AT DEMOSPLASH 2021"
+20 PRINT CHR$(4);"CATALOG"
+25 PRINT:PRINT "AUTOMATICALLY STARTING"
+30 PRINT "]BRUN D2"
+40 PRINT CHR$(4);"BRUN D2"

demos/d2/interrupt_handler.s

@@ -54,13 +54,13 @@ loop_forever:
 	lda	#0
 	sta	SONG_OFFSET
 
-	lda	#<peasant_song
-	sta	SONG_L
-	lda	#>peasant_song
-	sta	SONG_H
+;	lda	#<peasant_song
+;	sta	SONG_L
+;	lda	#>peasant_song
+;	sta	SONG_H
 
 
-	jmp	try_again
+	beq	try_again		; bra
 all_ok:
 
 	; see if note
@@ -117,10 +117,11 @@ blah_blah:
 y_smc:
 	ldy	#0
 	iny
-	bne	not_wrap2
-	inc	SONG_H
-not_wrap2:
-	jmp	set_notes_loop
+
+;	bne	not_wrap2		; assume less than 256 bytes
+;	inc	SONG_H
+;not_wrap2:
+	bne	set_notes_loop		; bra
 
 handle_timing:
 	; was timing

demos/d2/moving.s

@@ -86,20 +86,6 @@ ror_nop_smc:
 
 	jsr	flip_page
 
-;flip_pages:
-
-	; Y should be $FF here
-
-;	lda	HGR_PAGE	; will be $20/$40
-;	cmp	#$20
-;	bne	done_page
-;	dey
-;done_page:
-;	ldx	PAGE1-$FE,Y	; set display page to PAGE1 or PAGE2
-
-;	eor	#$60		; flip draw page between $2000/$4000
-;	sta	HGR_PAGE
-
 	lda	FRAME
 	cmp	#$1b		; NOTE: NEEDS TO BE ODD
 	bne	draw_moving	; bra