Pong

I forgot to commit for a while and I haven't done much, but got the very basics of the game pong working.

Signed-off-by: deadvey <deadvey@deadvey.com>

source/features/graphics.asm

@@ -16,8 +16,6 @@ os_set_graphics_mode:
 ; y_start
 ; colour
 os_draw_graphical_rectangle:
-	pusha
-
 	; Tell BIOS we're changing 'da pixels!
 	mov ah, 0Ch
 
@@ -28,21 +26,28 @@ os_draw_graphical_rectangle:
 
 	jmp .x_loop
 
-	.x_loop:
-		int 10h
-		cmp cx, [x_end]
-		je .next_row
-		inc cx
-		call .x_loop
+.x_loop:
+   int 10h
+   cmp cx, [x_end]
+   je .next_row
+   inc cx
+   call .x_loop
 
-	.next_row:
-		mov cx, [x_start]
-		cmp dx, [y_end]
-		je .finish
-		inc dx					; Increase Row
-		call .x_loop
+.next_row:
+   mov cx, [x_start]
+   cmp dx, [y_end]
+   je .finish
+   inc dx					; Increase Row
+   call .x_loop
 
-	.finish:
-		popa
-		Iret
+.finish:
+   ret
+
+
+section .data
+	x_start dw 0
+	y_start dw 0
+	x_end dw 0
+	y_end dw 0
+	colour db 1111b
 

source/features/screen.asm~

@@ -1,162 +0,0 @@
-; ==================================================================
-; MikeOS -- The Mike Operating System kernel
-; Copyright (C) 2006 - 2021 MikeOS Developers -- see doc/LICENSE.TXT
-;
-; SCREEN HANDLING SYSTEM CALLS
-; ==================================================================
-
-; ------------------------------------------------------------------
-; os_print_string -- Displays text
-; IN: SI = message location (zero-terminated string)
-; OUT: Nothing (registers preserved)
-
-os_print_string:
-	pusha
-
-	mov ah, 0Eh			; int 10h teletype function, we're telling the BIOS we will print something
-
-.repeat:
-	lodsb				; Get char from si into al
-	cmp al, 0			; Compare al to 0
-	je .done			; If char is zero, end of string
-
-	int 10h				; Otherwise, print it
-	jmp .repeat			; And move on to next char
-
-.done:
-	popa
-	ret
-
-; Exact same as the above procedure, but this adds a newline 
-; after priting, similar to the difference between Rust's print! and println!
-os_print_string_nl:				pusha
-
-	mov ah, 0Eh			; int 10h teletype function, we're telling the BIOS we will print something
-
-.repeat:
-	lodsb				; Get char from si into al
-	cmp al, 0			; Compare al to 0
-	je .done			; If char is zero, end of string
-
-	int 10h				; Otherwise, print it
-	jmp .repeat			; And move on to next char
-
-.done:
-	call os_print_newline
-	popa
-	ret
-
-; --------------------------------------------
-
-os_print_newline:
-	pusha
-
-	mov ah, 03h
-	int 10h
-	
-	mov ah, 02h
-	add dh, 1
-	mov dl, 0
-	int 10h
-	
-	popa
-	ret
-		
-
-; -------------------------------------------
-
-os_clear_screen:
-        pusha
-
-	mov ah, 00h
-	mov al, 03h 		; Set video mode to textmode (80x25). 16 colors, 8 pages
-	int 10h
-
-	mov ah, 02h
-	mov dh, 0
-	mov dl, 0
-	int 10h
-
-        popa
-        ret
-
-; -------------------------------------------
-
-; AX = key pressed
-os_read_input:
-	mov ah, 11h			; BIOS call to check for key
-	int 16h				; Interrupt
-	jnz .key_pressed		; Jump if input isn't 0
-	
-	hlt
-	jmp os_read_input
-
-.key_pressed:
-	mov ah, 10h
-	int 16h
-	ret
-
-; -------------------------------------------
-
-os_display_input:	
-	pusha
-	mov cx, prompt_length ; Characters remaining
-	
-.loop:
-	call .check_key_pressed
-
-        jmp .loop
-
-.check_key_pressed:	
-        call os_read_input
-
-	cmp al, 08h
-	je .backspace
-
-	cmp al, 0Dh
-	je .enter_key
-
-	cmp al, 1Bh
-	je .esc_key
-
-	dec cx
-	call .print_current_input
-	ret
-
-.esc_key:
-	call os_reboot
-
-.enter_key:
-	mov al, 0
-	stosb
-	mov di, user_input
-	popa
-	call os_read_cli
-
-.backspace:
-	cmp cx, prompt_length			; If bx < 20
-	jl .move_cursor_back			; then .move_cursor_back
-	call .loop				; Else .loop
-
-.move_cursor_back:
-	mov ah, 0Eh
-
-	mov al, 08h
-	int 10h
-	mov al, 20h
-	int 10h
-	mov al, 08h
-	int 10h
-
-	dec di
-	inc cx
-	jmp os_display_input
-
-.print_current_input:
-	stosb
-	
-	mov ah, 0Eh
-	int 10h
-
-
-	ret