rotozoom: more optimizations from qkumba

graphics/gr/plasma/plasma.s

@@ -130,6 +130,9 @@ plot_yloop:
 plot_mask:
 	sty	MASK
 
+	; ugh can't use PLOT trick as it always will draw something
+	; to PAGE1 even if we don't want to
+
 	jsr	GBASCALC	; point GBASL/H to address in (A is ycoord/2)
 				; after, A is GBASL, C is clear
 

graphics/gr/rotozoom/Makefile

@@ -6,11 +6,12 @@ LINKERSCRIPTS = ../../../linker_scripts
 
 all:	roto.dsk make_sine_table
 
-roto.dsk:	HELLO ROTO ROTOPLASMA
+roto.dsk:	HELLO ROTO ROTOPLASMA ROTOPLASMA_TINY
 	cp empty.dsk roto.dsk
 	$(DOS33) -y roto.dsk SAVE A HELLO
 	$(DOS33) -y roto.dsk BSAVE -a 0x1000 ROTO
 	$(DOS33) -y roto.dsk BSAVE -a 0x1000 ROTOPLASMA
+	$(DOS33) -y roto.dsk BSAVE -a 0x1000 ROTOPLASMA_TINY
 
 ###
 
@@ -33,6 +34,15 @@ ROTOPLASMA:	rotoplasma.o
 rotoplasma.o:	rotoplasma.s rotozoom_texture.s plasma.s
 	ca65 -o rotoplasma.o rotoplasma.s -l rotoplasma.lst
 
+###
+
+ROTOPLASMA_TINY:	rotoplasma_tiny.o
+	ld65 -o ROTOPLASMA_TINY rotoplasma_tiny.o -C $(LINKERSCRIPTS)/apple2_1000.inc
+
+rotoplasma_tiny.o:	rotoplasma_tiny.s rotozoom_texture.s plasma.s
+	ca65 -o rotoplasma_tiny.o rotoplasma_tiny.s -l rotoplasma_tiny.lst
+
+
 
 ###
 
@@ -45,4 +55,4 @@ make_sine_table.o:	make_sine_table.c
 ###
 
 clean:	
-	rm -f *~ *.o *.lst ROTO ROTOPLASMA make_sine_table
+	rm -f *~ *.o *.lst ROTO ROTOPLASMA ROTOPLASMA_TINY make_sine_table

graphics/gr/rotozoom/rotoplasma_tiny.s

@@ -0,0 +1,170 @@
+; rotozoom with cycling plasma texture
+;
+
+; TODO:
+;	make angle 64 degrees?
+;	remove scaling step?
+;	cycle between all four color schemes?
+
+
+
+.include "zp.inc"
+.include "hardware.inc"
+
+	;================================
+	; Clear screen and setup graphics
+	;================================
+
+	jsr	HOME
+	bit	PAGE0			; set page 0
+	bit	LORES			; Lo-res graphics
+	bit	FULLGR			; mixed gr/text mode
+	bit	SET_GR			; set graphics
+
+	lda	#0
+	sta	DISP_PAGE
+	lda	#4
+	sta	DRAW_PAGE
+
+	;===================================
+	; Clear top/bottom of page 0 and 1
+	;===================================
+
+;	jsr	clear_screens
+
+	;===================================
+	; init the multiply tables
+	;===================================
+
+	jsr	init_multiply_tables
+
+	;======================
+	; init plasma texture
+	;======================
+
+	jsr	init_plasma_texture
+
+	;=================================
+	; main loop
+
+	lda	#0
+	sta	ANGLE
+	sta	SCALE_F
+	sta	FRAMEL
+
+	lda	#1
+	sta	SCALE_I
+
+main_loop:
+	jsr	update_plasma
+
+	jsr	rotozoom
+
+	jsr	page_flip
+
+wait_for_keypress:
+;	lda	KEYPRESS
+;	bpl	wait_for_keypress
+;	bit	KEYRESET
+
+
+	clc
+	lda	FRAMEL
+	adc	direction
+	sta	FRAMEL
+
+	cmp	#$f8
+	beq	back_at_zero
+	cmp	#33
+;	beq	at_far_end
+	beq	back_at_zero
+	bne	done_reverse
+
+back_at_zero:
+	; change plasma color
+
+	inc	which_color
+	lda	which_color
+	cmp	#4
+	bne	refresh_color
+	lda	#0
+	sta	which_color
+refresh_color:
+	asl
+	tay
+
+	lda	colorlookup,Y
+	sta	color_lookup_smc+1
+;	sta	colorlookup2_smc+1
+	lda	colorlookup+1,Y
+	sta	color_lookup_smc+2
+;	sta	colorlookup2_smc+2
+
+at_far_end:
+
+	; change bg color
+
+	; reverse direction
+	lda	direction
+	eor	#$ff
+	clc
+	adc	#1
+	sta	direction
+
+	lda	scaleaddl
+	eor	#$ff
+	clc
+	adc	#1
+	sta	scaleaddl
+
+	lda	scaleaddh
+	eor	#$ff
+	adc	#0
+	sta	scaleaddh
+
+done_reverse:
+
+
+	clc
+	lda	ANGLE
+	adc	direction
+	and	#$3f
+	sta	ANGLE
+
+	; increment zoom
+
+;	clc
+;	lda	SCALE_F
+;	adc	scaleaddl
+;	sta	SCALE_F
+;	lda	SCALE_I
+;	adc	scaleaddh
+;	sta	SCALE_I
+
+	jmp	main_loop
+
+
+direction:	.byte	$01
+scaleaddl:	.byte	$10
+scaleaddh:	.byte	$00
+
+;===============================================
+; External modules
+;===============================================
+
+.include "rotozoom_texture.s"
+.include "plasma.s"
+
+.include "gr_pageflip.s"
+.include "gr_fast_clear.s"
+.include "gr_copy.s"
+;.include "decompress_fast_v2.s"
+
+.include "gr_offsets.s"
+.include "c00_scrn_offsets.s"
+
+.include "multiply_fast.s"
+
+;===============================================
+; Data
+;===============================================

graphics/gr/rotozoom/rotozoom.s

@@ -22,6 +22,7 @@
 ;	$39dc9=237,001=		change to use common lookup table (outside inner loop)
 ;	$3399f=211,359=4.73fps	unroll the Y loop by one
 ;	$2BA83=178,819=5.59fps	optimize unrolled loop
+;	$2B14B=176,459=5.66fps	avoid extra jump (qkumba)
 
 CAL	= $B0
 CAH	= $B1
@@ -265,13 +266,7 @@ roto_color_even_smc:
 	; carry was set a bit before to low bit of YPH
 	; hopefully nothing has cleared it
 
-	bcs	rscrn_adjust_odd					; 2nt/3
+	bcc	rscrn_adjust_even					; 2nt/3
-
-rscrn_adjust_even:
-
-	; YP was even so want bottom nibble
-	and	#$f							; 2
-	jmp	rscrn_done						; 3
 
 rscrn_adjust_odd:
 	; YP was odd so want top nibble
@@ -280,6 +275,13 @@ rscrn_adjust_odd:
 	lsr								; 2
 	lsr								; 2
 
+	; fall through
+
+rscrn_adjust_even:
+
+	; YP was even so want bottom nibble
+	and	#$f							; 2
+
 rscrn_done: