; Copyright (c) 1996 Brian Fisher
; All rights reserved.
;
; Redistribution and use in source and binary forms, with or without
; modification, are permitted provided that the following conditions
; are met:
; 1. Redistributions of source code must retain the above copyright
;    notice, this list of conditions and the following disclaimer.
; 2. Redistributions in binary form must reproduce the above copyright
;    notice, this list of conditions and the following disclaimer in the
;    documentation and/or other materials provided with the distribution.
; 3. The name of the author may not be used to endorse or promote products
;    derived from this software without specific prior written permission.
;
; THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
; IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
; OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
; IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
; INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
; NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
; DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
; THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
; (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
; THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
;****************************************************************************
;*
;*
;*** putpixel and readpixel for mode x
;* By Brian Fisher
;*
;*
.286
Ideal 
Model Small
Public Putpixel,Readpixel,Rectangle

CodeSeg

Proc Putpixel   ;  Xloc,  Yloc,  Color, page
		;   12     10      8      6
	push bp
	mov bp,sp
	push es di
	
	mov ax,[ss:bp+10]
	mov bx,ax
	shl ax,6
	shl bx,4
	add ax,bx
	mov bx,[ss:bp+12]
	shr bx,2
	add ax,bx
	mov di,ax
	mov ax,[ss:bp+06]
	shl ax,14
	add di,ax
	mov cx,[ss:bp+12]
	and cl,3
	mov bl,1
	shl bl,cl
	mov dx,03c4h
	mov al,02h
	mov ah,bl
	out dx,ax
	mov ax,0a000h
	mov es,ax
	mov ax,[ss:bp+08]
	mov [es:di],al

	pop di es bp
	retf 8
endp    Putpixel
Proc    Readpixel  ;  Xloc,  Yloc,  page
		   ;   10      8     6
	push bp
	mov bp,sp
	push ds si
	
	mov ax,[ss:bp+08]
	mov bx,ax
	shl ax,6
	shl bx,4
	add ax,bx
	mov bx,[ss:bp+10]
	shr bx,2
	add ax,bx
	mov si,[ss:bp+06]
	shl si,14
	add si,ax
	mov cx,[ss:bp+10]
	and cl,3
	mov dx,03ceh
	mov al,04h
	mov ah,cl
	out dx,ax
	mov ax,0a000h
	mov ds,ax
	mov al,[ds:si]
	xor ah,ah

	pop si ds bp
	retf 6
endp    Readpixel
Proc    Rectangle       ;x, y, width, height, color, page
	push bp
	mov bp,sp
	push es ds si di

	cld
	mov ax,[ss:bp+14]       ;figure out the starting vga offset
	mov bx,ax
	shl ax,6
	shl bx,4
	add ax,bx
	mov bx,[ss:bp+16]
	shr bx,2
	add bx,ax
	mov ax,[ss:bp+06]
	shl ax,14
	add bx,ax
	mov si,bx
	mov cx,[ss:bp+16]       ;figure out the plane of the first pixel
	and cl,3
	mov bx,1
	shl bl,cl
	xor cx,cx
	mov ax,0a000h           ;set up es
	mov es,ax
xlop:
	mov di,si
	mov al,02h              ;set the plane write enable
	mov dx,03c4h
	mov ah,bl
	out dx,ax
	xor dl,dl               ;clear dl for the y-counter
ylop:
	mov al,[ss:bp+08]
	mov [es:di],al
	add di,50h
	inc dl
	mov al,[ss:bp+10]
	cmp dl,al
	jb ylop
	inc cx
	shl bl,1
	mov ax,bx
	shr al,4
	add bl,al
	and bx,15
	add si,ax
	mov ax,[ss:bp+12]
	cmp cx,ax
	jb xlop
	pop di si ds es bp
	retf 12
endp    rectangle
end