Initial commit of Command & Conquer Red Alert source code.

WINVQ/VQM32/MCGABUF.ASM

@@ -0,0 +1,196 @@
+;
+;	Command & Conquer Red Alert(tm)
+;	Copyright 2025 Electronic Arts Inc.
+;
+;	This program is free software: you can redistribute it and/or modify
+;	it under the terms of the GNU General Public License as published by
+;	the Free Software Foundation, either version 3 of the License, or
+;	(at your option) any later version.
+;
+;	This program is distributed in the hope that it will be useful,
+;	but WITHOUT ANY WARRANTY; without even the implied warranty of
+;	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;	GNU General Public License for more details.
+;
+;	You should have received a copy of the GNU General Public License
+;	along with this program.  If not, see <http://www.gnu.org/licenses/>.
+;
+
+;****************************************************************************
+;*
+;*        C O N F I D E N T I A L -- W E S T W O O D  S T U D I O S
+;*
+;*---------------------------------------------------------------------------
+;*
+;* FILE
+;*     mcgabuf.asm
+;*
+;* DESCRIPTION
+;*     MCGA display routines. (32-Bit protected mode)
+;*
+;* PROGRAMMER
+;*     Bill Randolph
+;*     Denzil E. Long, Jr.
+;*
+;* DATE
+;*     Febuary 3, 1995
+;*
+;*---------------------------------------------------------------------------
+;*
+;* PUBLIC
+;*     ClearVRAM       - Clear all VRAM.
+;*     MCGA_BufferCopy - Copy 320x200 buffer to MCGA VRAM
+;*     MCGA_Blit       - Bit blit a block to the MCGA screen.
+;*
+;****************************************************************************
+
+	IDEAL
+	P386
+	MODEL	USE32 FLAT
+	LOCALS	??
+	INCLUDE	"vga.i"
+	CODESEG
+
+;****************************************************************************
+;*
+;* NAME
+;*     ClearVRAM - Clear all VRAM.
+;*
+;* SYNOPSIS
+;*     ClearVRAM()
+;*
+;*     void ClearVRAM(void);
+;*
+;* FUNCTION
+;*
+;* INPUTS
+;*     NONE
+;*
+;* RESULT
+;*     NONE
+;*
+;****************************************************************************
+
+	GLOBAL	C ClearVRAM:NEAR
+ 	PROC	ClearVRAM C NEAR USES eax ecx edi es
+
+	IF	PHARLAP_TNT
+	mov	eax,01Ch	;Set ES selector to video memory
+	mov	es,ax
+	mov	edi,0
+	ELSE
+	mov	edi,0A0000h
+	ENDIF
+
+	SET_PLANE 0Fh	;Enable all planes for writing
+	cld
+	mov	ecx,16000	;Clear 320x200
+	xor	eax,eax
+	rep	stosd
+	ret
+
+	ENDP	ClearVRAM
+
+
+;****************************************************************************
+;*
+;* NAME
+;*     MCGA_BufferCopy - Copy 320x200 buffer to MCGA VRAM
+;*
+;* SYNOPSIS
+;*     MCGA_BufferCopy(Buffer, Dummy)
+;*
+;*     void MCGA_BufferCopy(char *, char *);
+;*
+;* FUNCTION
+;*
+;* INPUTS
+;*     Buffer - Pointer to buffer to transfer.
+;*     Dummy  - Prototype placeholder.
+;*
+;* RESULT
+;*     NONE
+;*
+;****************************************************************************
+
+	GLOBAL	C MCGA_BufferCopy:NEAR
+	PROC	MCGA_BufferCopy C NEAR USES ecx esi edi es
+
+	ARG	buffer:NEAR PTR
+	ARG	dummy:NEAR PTR
+
+	IF	PHARLAP_TNT
+	mov	eax,01Ch
+	mov	es,ax
+	mov	edi,0
+	ELSE
+	mov	edi,0A0000h
+	ENDIF
+
+	mov	esi, [buffer]
+	mov	ecx,16000
+	rep 	movsd	;Transfer the data
+	ret
+
+	ENDP	MCGA_BufferCopy
+
+
+;****************************************************************************
+;*
+;* NAME
+;*     MCGA_Blit - Bit blit a block to the MCGA screen.
+;*
+;* SYNOPSIS
+;*     MCGA_Blit(Buffer, Screen, Width, Height)
+;*
+;*     void MCGA_Blit(char *, char *, long, long);
+;*
+;* FUNCTION
+;*
+;* INPUTS
+;*     Buffer - Pointer to buffer to copy.
+;*     Screen - Screen address to copy buffer to.
+;*     Width  - Width of block.
+;*     Height - Height of block.
+;*
+;* RESULT
+;*     NONE
+;*
+;****************************************************************************
+
+	GLOBAL	C MCGA_Blit:NEAR
+	PROC	MCGA_Blit C NEAR USES ecx edx esi edi
+
+	ARG	buffer:NEAR PTR
+	ARG	screen:NEAR PTR
+	ARG	imgwidth:DWORD
+	ARG	imgheight:DWORD
+
+	IF	PHARLAP_TNT
+	push	es
+	mov	eax,1Ch	;Set ES selector to VRAM
+	mov	es,ax
+	ENDIF
+
+	mov	esi,[buffer]
+	mov	edi,[screen]
+	mov	edx,320
+	sub	edx,[imgwidth]	;Compute modulo
+
+??Do_row:
+	mov	ecx,[imgwidth]
+	rep 	movsb
+	add	edi,edx
+	dec	[imgheight]
+	jnz	??Do_row
+
+	IF	PHARLAP_TNT
+	pop	es
+	ENDIF
+
+	ret
+
+	ENDP	MCGA_Blit
+
+	END
+