From 4d846e778bd43f6950de8f0be89aa65f7ec5fb29 Mon Sep 17 00:00:00 2001
From: Vince Weaver <vincent.weaver@maine.edu>
Date: Fri, 12 May 2017 14:29:21 -0400
Subject: [PATCH] tfv: initial screen copy routine

---
 gr-sim/gr-sim.c     | 31 ++++++++++++++----
 tfv/Makefile        |  5 +--
 tfv/apple2_1000.inc | 12 +++++++
 tfv/tfv.s           | 79 ++++++++++++++++++++++++++++++++++++++++++---
 4 files changed, 114 insertions(+), 13 deletions(-)
 create mode 100644 tfv/apple2_1000.inc

diff --git a/gr-sim/gr-sim.c b/gr-sim/gr-sim.c
index 82bb5462..61abdbfb 100644
--- a/gr-sim/gr-sim.c
+++ b/gr-sim/gr-sim.c
@@ -605,23 +605,40 @@ short gr_addr_lookup[48]={
 
 int grsim_put_sprite(unsigned char *sprite_data, int xpos, int ypos) {
 
-	int i,j,xsize,ysize;
+	unsigned char i;
 	unsigned char *ptr;
 	short address;
+
 	ptr=sprite_data;
-	xsize=*ptr;
+	x=*ptr;
 	ptr++;
-	ysize=*ptr;
+	ram[CV]=*ptr;
 	ptr++;
 
-	for(j=0;j<ysize;j++) {
-		address=gr_addr_lookup[(ypos+j)/2];
+	while(1) {
+		address=gr_addr_lookup[ypos/2];
 		address+=xpos;
-		for(i=0;i<xsize;i++) {
-			if (*ptr) ram[address]=*ptr;
+		for(i=0;i<x;i++) {
+			a=*ptr;
+			if (a==0) {
+			}
+			else if ((a&0xf0)==0) {
+				ram[address]&=0xf0;
+				ram[address]|=a;
+			}
+			else if ((a&0x0f)==0) {
+				ram[address]&=0x0f;
+				ram[address]|=a;
+			}
+			else {
+				ram[address]=a;
+			}
 			ptr++;
 			address++;
 		}
+		ypos++;
+		ram[CV]--;
+		if (ram[CV]==0) break;
 	}
 
 	return 0;
diff --git a/tfv/Makefile b/tfv/Makefile
index e68266d5..7718061b 100644
--- a/tfv/Makefile
+++ b/tfv/Makefile
@@ -6,12 +6,12 @@ PNG2GR = ../gr-utils/png2gr
 all:	tfv.dsk
 
 tfv.dsk:	TITLE.GR TFV ED
-	$(DOS33) -y tfv.dsk BSAVE -a 0xc00 TFV
+	$(DOS33) -y tfv.dsk BSAVE -a 0x1000 TFV
 	$(DOS33) -y tfv.dsk BSAVE -a 0x400 TITLE.GR
 	$(DOS33) -y tfv.dsk BSAVE -a 0x900 ED
 
 TFV:	tfv.o
-	ld65 -o TFV tfv.o -C ./apple2_c00.inc
+	ld65 -o TFV tfv.o -C ./apple2_1000.inc
 
 tfv.o:	tfv.s title.inc
 	ca65 -o tfv.o tfv.s -l tfv.lst
@@ -27,3 +27,4 @@ TITLE.GR:	title.png
 
 clean:	
 	rm -f *~ TITLE.GR *.o *.lst ED
+
diff --git a/tfv/apple2_1000.inc b/tfv/apple2_1000.inc
new file mode 100644
index 00000000..e22976de
--- /dev/null
+++ b/tfv/apple2_1000.inc
@@ -0,0 +1,12 @@
+MEMORY {
+       ZP: start = $00, size = $1A, type = rw;
+       RAM: start = $1000, size = $8E00, file = %O;
+}
+
+SEGMENTS {
+CODE: load = RAM, type = ro;
+RODATA: load = RAM, type = ro;
+DATA: load = RAM, type = rw;
+BSS: load = RAM, type = bss, define = yes;
+ZEROPAGE: load = ZP, type = zp;
+}
diff --git a/tfv/tfv.s b/tfv/tfv.s
index 98fd85f5..ab36385a 100644
--- a/tfv/tfv.s
+++ b/tfv/tfv.s
@@ -40,9 +40,13 @@ MASK	EQU $2E
 COLOR	EQU $30
 FIRST	EQU $F0
 
-TEMP	EQU $FA
-RUN	EQU $FA
-TEMP2	EQU $FB
+TEMP	EQU	$FA
+RUN	EQU	$FA
+TEMP2	EQU	$FB
+INL	EQU	$FC
+INH	EQU	$FD
+OUTL	EQU	$FE
+OUTH	EQU	$FF
 
 	;=============================
 	; set low-res graphics, page 0
@@ -55,6 +59,10 @@ TEMP2	EQU $FB
 	;=================
 	jsr     CLRTOP
 
+	lda	#$c
+	sta	BASH
+	lda	#$0
+	sta	BASL			; load image off-screen 0xc00
 
 	lda     #>(title_image)
         sta     GBASH
@@ -62,14 +70,22 @@ TEMP2	EQU $FB
         sta     GBASL
 	jsr	load_rle_gr
 
+	jsr	gr_copy
+
 	lda	#$4
 	sta	BASH
 	lda	#$0
-	sta	BASL			; 0x400 is GR page 0
+	sta	BASL			; restore to 0x400 (page 0)
+					; copy to 0x400 (page 0)
+
 
 	; Return to BASIC?
 	rts
 
+;=====================================================================
+;= ROUTINES
+;=====================================================================
+
 	;=================
 	; load RLE image
 	;=================
@@ -184,4 +200,59 @@ set_gr_page0:
 	bit	GR			; set graphics
 	rts
 
+	;=========================================================
+	; gr_copy
+	;=========================================================
+	; for now copy 0xc00 to 0x400
+	; 2 + 8*38 + 4*80*23 + 4*120*26 + 13 = 20,159 = 20ms = 50Hz
+gr_copy:
+	ldx	#0		; set y to zero				; 2
+
+gr_copy_loop:
+	stx	TEMP		; save y				; 3
+	txa			; move to A				; 2
+	asl			; mult by 2				; 2
+	tay			; put into Y				; 2
+	lda	gr_offsets,Y	; lookup low byte for line addr		; 5
+	sta	OUTL		; out and in are the same		; 3
+	sta	INL							; 3
+	lda	gr_offsets+1,Y	; lookup high byte for line addr	; 5
+	sta	OUTH							; 3
+	adc	#$8		; for now, fixed 0xc			; 2
+	sta	INH							; 3
+	ldx	TEMP		; restore y				; 3
+
+	ldy	#0		; set X counter to 0			; 2
+gr_copy_line:
+	lda     (INL),Y		; load a byte				; 5
+	sta     (OUTL),Y	; store a byte				; 6
+	iny			; increment pointer			; 2
+
+	cpx	#$4		; don't want to copy bottom 4*40	; 2
+	bcs	gr_copy_above4						; 3
+
+gr_copy_below4:
+	cpy	#120		; for early ones, copy 120 bytes	; 2
+	bne	gr_copy_line						; 3
+	beq	gr_copy_line_done					; 3
+
+gr_copy_above4:			; for last four, just copy 80 bytes
+	cpy	#80							; 2
+	bne	gr_copy_line						; 3
+
+gr_copy_line_done:
+	inx			; increment y value			; 2
+	cpx	#8		; there are 8 of them			; 2
+	bne	gr_copy_loop	; if not, loop				; 3
+	rts								; 6
+
+	; waste memory with a lookup table
+	; maybe faster than using GBASCALC?
+gr_offsets:
+	.word	$400,$480,$500,$580,$600,$680,$700,$780
+	.word 	$428,$4a8,$528,$5a8,$628,$6a8,$728,$7a8
+	.word	$450,$4d0,$550,$5d0,$650,$6d0,$750,$7d0
+
+
+
 .include "title.inc"