duke: add help screen

duke/Makefile

@@ -26,6 +26,7 @@ DUKE:	duke.o
 	ld65 -o DUKE duke.o -C ../linker_scripts/apple2_2000.inc
 
 duke.o:	duke.s zp.inc hardware.inc duke.s \
+	print_help.s \
 	graphics/duke_graphics.inc \
 	maps/level1_map.lzsa \
 	status_bar.s draw_duke.s gr_putsprite_crop.s \

duke/draw_duke.s

@@ -6,6 +6,8 @@ move_duke:
 
 	jsr	check_falling
 
+	jsr	handle_jumping
+
 	lda	DUKE_WALKING
 	beq	done_move_duke
 
@@ -63,11 +65,30 @@ duke_collide:
 
 	rts
 
+
+	;=========================
+	; check_jumping
+	;=========================
+handle_jumping:
+
+	lda	DUKE_JUMPING
+	beq	done_handle_jumping
+
+	dec	DUKE_Y
+	dec	DUKE_Y
+	dec	DUKE_JUMPING
+
+done_handle_jumping:
+	rts
+
 	;=========================
 	; check_falling
 	;=========================
 check_falling:
 
+	lda	DUKE_JUMPING
+	bne	done_check_falling
+
 	; check below feet
 
 	; block index below feet is (y+10)*16/4 + (x/2) + 1
@@ -100,7 +121,7 @@ check_falling:
 	jsr	copy_tilemap_subset
 
 done_check_below:
-
+done_check_falling:
 	rts
 
 

duke/duke.s

@@ -159,6 +159,7 @@ done_with_duke:
 	.include	"status_bar.s"
 	.include	"keyboard.s"
 	.include	"joystick.s"
+	.include	"print_help.s"
 
 	.include	"draw_duke.s"
 	.include	"handle_laser.s"

duke/keyboard.s

@@ -78,13 +78,20 @@ keypress:
 
 check_sound:
 	cmp	#$14			; control-T
-	bne	check_joystick
+	bne	check_help
 
 	lda	SOUND_STATUS
 	eor	#SOUND_DISABLED
 	sta	SOUND_STATUS
 	jmp	done_keypress
 
+check_help:
+	cmp	#'H'			; H (^H is same as left)
+	bne	check_joystick
+
+	jsr	print_help
+	jmp	done_keypress
+
 	; can't be ^J as that's the same as down
 check_joystick:
 	cmp	#'J'			; J
@@ -163,7 +170,7 @@ check_down:
 	cmp	#'S'
 	beq	down_pressed
 	cmp	#$0A
-	bne	check_return
+	bne	check_space
 down_pressed:
 	lda	CURSOR_Y		; if 48<y<$EE don't decrement
 	cmp	#48
@@ -182,6 +189,11 @@ check_space:
 space_pressed:
 
 	; jump
+	lda	DUKE_JUMPING
+	bne	done_keypress	; don't jump if already jumping
+
+	lda	#5
+	sta	DUKE_JUMPING
 
 	jmp	done_keypress
 

duke/print_help.s

@@ -0,0 +1,32 @@
+; For Help press ^H
+
+print_help:
+	bit	KEYRESET		; clear keyboard
+	bit	SET_TEXT
+	jsr	HOME
+
+	lda	#<help_text
+	sta	OUTL
+	lda	#>help_text
+	sta	OUTH
+	jsr	move_and_print_list
+
+	jsr	page_flip
+
+wait_for_keypress:
+	lda     KEYPRESS
+	bpl	wait_for_keypress
+	bit	KEYRESET
+
+
+	bit	SET_GR
+	rts
+
+help_text:
+.byte 0, 5,"CONTROLS:",0
+.byte 3, 6,   "A OR <-      : MOVE LEFT",0
+.byte 3, 7,   "D OR ->      : MOVE RIGHT",0
+.byte 3, 8,   "SPACEBAR     : JUMP",0
+.byte 3,11,   "RETURN       : SHOOT LASER",0
+.byte 3,12,   "ESC          : QUITS",0
+.byte 255

duke/status_bar.s

@@ -22,7 +22,7 @@ draw_status_bar:
 
 
 help_string:
-	.byte 3,20,"        PRESS ^H FOR HELP         ",0
+	.byte 3,20,"        PRESS 'H' FOR HELP        ",0
 
 score_string:
 	;           012456789012345678901234567890123456789

duke/text_print.s

@@ -90,7 +90,7 @@ done_print_string:
 
 	rts
 
-.if 0
+
 	;================================
 	; move and print a list of lines
 	;================================
@@ -103,7 +103,7 @@ move_and_print_list:
 	rts
 
 
-
+.if 0
 	;================================
 	; move and print a list of lines
 	;================================