Initial revision

2 files changed, 1632 insertions, 0 deletions

diff --git a/src/mesa/drivers/dos/DEPEND.DOS b/src/mesa/drivers/dos/DEPEND.DOS
new file mode 100644
index 0000000000..60a0fdcc28
--- /dev/null
+++ b/src/mesa/drivers/dos/DEPEND.DOS
@@ -0,0 +1,119 @@
+# DO NOT DELETE

+

+accum.obj: accum.h types.h ..\include\GL\gl.h config.h fixed.h dd.h context.h

+accum.obj: dlist.h macros.h

+alpha.obj: alpha.h types.h ..\include\GL\gl.h config.h fixed.h dd.h context.h

+alpha.obj: dlist.h macros.h

+alphabuf.obj: alphabuf.h types.h ..\include\GL\gl.h config.h fixed.h dd.h

+alphabuf.obj: context.h macros.h

+api1.obj: api.h bitmap.h types.h ..\include\GL\gl.h config.h fixed.h dd.h context.h

+api1.obj: eval.h image.h macros.h matrix.h teximage.h

+api2.obj: api.h bitmap.h types.h ..\include\GL\gl.h config.h fixed.h dd.h context.h

+api2.obj: eval.h image.h macros.h matrix.h teximage.h

+attrib.obj: attrib.h types.h ..\include\GL\gl.h config.h fixed.h dd.h context.h

+attrib.obj: draw.h dlist.h macros.h

+bitmap.obj: bitmap.h types.h ..\include\GL\gl.h config.h fixed.h dd.h context.h

+bitmap.obj: feedback.h image.h macros.h pb.h

+blend.obj: alphabuf.h types.h ..\include\GL\gl.h config.h fixed.h dd.h blend.h

+blend.obj: context.h dlist.h macros.h pb.h span.h

+bresenhm.obj: bresenhm.h types.h ..\include\GL\gl.h config.h fixed.h dd.h

+clip.obj: clip.h types.h ..\include\GL\gl.h config.h fixed.h dd.h context.h

+clip.obj: dlist.h macros.h matrix.h vb.h xform.h

+context.obj: context.h types.h ..\include\GL\gl.h config.h fixed.h dd.h depth.h

+context.obj: draw.h eval.h light.h lines.h dlist.h macros.h pb.h points.h

+context.obj: pointers.h triangle.h teximage.h texobj.h texture.h vb.h vertex.h

+copypix.obj: context.h types.h ..\include\GL\gl.h config.h fixed.h dd.h

+copypix.obj: copypix.h depth.h feedback.h dlist.h macros.h pixel.h span.h

+copypix.obj: stencil.h

+depth.obj: context.h types.h ..\include\GL\gl.h config.h fixed.h dd.h depth.h

+depth.obj: dlist.h macros.h

+dlist.obj: accum.h types.h ..\include\GL\gl.h config.h fixed.h dd.h alpha.h

+dlist.obj: attrib.h bitmap.h blend.h clip.h context.h copypix.h depth.h draw.h

+dlist.obj: drawpix.h enable.h eval.h feedback.h fog.h image.h light.h lines.h

+dlist.obj: dlist.h logic.h macros.h masking.h matrix.h misc.h pixel.h points.h

+dlist.obj: polygon.h scissor.h stencil.h texobj.h teximage.h texture.h vb.h

+dlist.obj: vertex.h winpos.h

+draw.obj: clip.h types.h ..\include\GL\gl.h config.h fixed.h dd.h context.h

+draw.obj: draw.h feedback.h fog.h light.h lines.h dlist.h macros.h matrix.h

+draw.obj: pb.h points.h texture.h vb.h xform.h

+drawpix.obj: context.h types.h ..\include\GL\gl.h config.h fixed.h dd.h

+drawpix.obj: drawpix.h feedback.h dlist.h macros.h pixel.h span.h stencil.h

+enable.obj: context.h types.h ..\include\GL\gl.h config.h fixed.h dd.h depth.h

+enable.obj: draw.h enable.h light.h dlist.h macros.h stencil.h

+eval.obj: context.h types.h ..\include\GL\gl.h config.h fixed.h dd.h draw.h

+eval.obj: eval.h dlist.h macros.h

+feedback.obj: context.h types.h ..\include\GL\gl.h config.h fixed.h dd.h

+feedback.obj: feedback.h dlist.h macros.h

+fog.obj: context.h types.h ..\include\GL\gl.h config.h fixed.h dd.h fog.h

+fog.obj: dlist.h macros.h

+get.obj: context.h types.h ..\include\GL\gl.h config.h fixed.h dd.h get.h

+get.obj: dlist.h macros.h

+hash.obj: hash.h

+interp.obj: interp.h types.h ..\include\GL\gl.h config.h fixed.h dd.h macros.h

+image.obj: image.h types.h ..\include\GL\gl.h config.h fixed.h dd.h macros.h

+image.obj: pixel.h

+light.obj: context.h types.h ..\include\GL\gl.h config.h fixed.h dd.h light.h

+light.obj: dlist.h macros.h matrix.h vb.h xform.h

+lines.obj: bresenhm.h types.h ..\include\GL\gl.h config.h fixed.h dd.h

+lines.obj: context.h feedback.h interp.h lines.h dlist.h macros.h pb.h vb.h

+logic.obj: context.h types.h ..\include\GL\gl.h config.h fixed.h dd.h dlist.h

+logic.obj: logic.h macros.h pb.h

+masking.obj: alphabuf.h types.h ..\include\GL\gl.h config.h fixed.h dd.h

+masking.obj: context.h macros.h masking.h pb.h

+matrix.obj: accum.h types.h ..\include\GL\gl.h config.h fixed.h dd.h alphabuf.h

+matrix.obj: context.h depth.h dlist.h macros.h matrix.h stencil.h

+misc.obj: accum.h types.h ..\include\GL\gl.h config.h fixed.h dd.h alphabuf.h

+misc.obj: context.h depth.h macros.h masking.h misc.h stencil.h

+pb.obj: alpha.h types.h ..\include\GL\gl.h config.h fixed.h dd.h alphabuf.h

+pb.obj: blend.h depth.h fog.h logic.h macros.h masking.h pb.h scissor.h

+pb.obj: stencil.h texture.h

+pixel.obj: context.h types.h ..\include\GL\gl.h config.h fixed.h dd.h dlist.h

+pixel.obj: macros.h pixel.h image.h span.h stencil.h

+points.obj: context.h types.h ..\include\GL\gl.h config.h fixed.h dd.h

+points.obj: feedback.h dlist.h macros.h pb.h span.h vb.h

+pointers.obj: accum.h types.h ..\include\GL\gl.h config.h fixed.h dd.h alpha.h

+pointers.obj: attrib.h bitmap.h blend.h clip.h context.h copypix.h depth.h

+pointers.obj: draw.h drawpix.h enable.h eval.h feedback.h fog.h get.h light.h

+pointers.obj: lines.h dlist.h logic.h macros.h masking.h matrix.h misc.h

+pointers.obj: pixel.h points.h polygon.h readpix.h scissor.h stencil.h

+pointers.obj: teximage.h texobj.h texture.h varray.h vb.h vertex.h winpos.h

+polygon.obj: context.h types.h ..\include\GL\gl.h config.h fixed.h dd.h

+polygon.obj: macros.h polygon.h

+readpix.obj: alphabuf.h types.h ..\include\GL\gl.h config.h fixed.h dd.h

+readpix.obj: context.h depth.h feedback.h dlist.h macros.h image.h readpix.h

+readpix.obj: span.h stencil.h

+scissor.obj: context.h types.h ..\include\GL\gl.h config.h fixed.h dd.h

+scissor.obj: macros.h dlist.h scissor.h

+span.obj: alpha.h types.h ..\include\GL\gl.h config.h fixed.h dd.h alphabuf.h

+span.obj: blend.h depth.h fog.h logic.h macros.h masking.h scissor.h span.h

+span.obj: stencil.h texture.h

+stencil.obj: context.h types.h ..\include\GL\gl.h config.h fixed.h dd.h dlist.h

+stencil.obj: macros.h pb.h stencil.h

+teximage.obj: context.h types.h ..\include\GL\gl.h config.h fixed.h dd.h

+teximage.obj: image.h macros.h pixel.h span.h teximage.h

+texobj.obj: context.h types.h ..\include\GL\gl.h config.h fixed.h dd.h macros.h

+texobj.obj: teximage.h texobj.h

+texture.obj: context.h types.h ..\include\GL\gl.h config.h fixed.h dd.h dlist.h

+texture.obj: macros.h pb.h teximage.h texture.h

+triangle.obj: depth.h types.h ..\include\GL\gl.h config.h fixed.h dd.h

+triangle.obj: feedback.h macros.h span.h triangle.h vb.h tritemp.h

+varray.obj: draw.h types.h ..\include\GL\gl.h config.h fixed.h dd.h context.h

+varray.obj: enable.h dlist.h macros.h varray.h vb.h xform.h

+vb.obj: types.h ..\include\GL\gl.h config.h fixed.h dd.h vb.h

+vertex.obj: draw.h types.h ..\include\GL\gl.h config.h fixed.h dd.h light.h

+vertex.obj: dlist.h macros.h vb.h vertex.h

+winpos.obj: ..\include\GL\gl.h draw.h types.h config.h fixed.h dd.h dlist.h

+winpos.obj: macros.h winpos.h

+xform.obj: types.h ..\include\GL\gl.h config.h fixed.h dd.h xform.h

+glx.obj: ..\include\GL\gl.h ..\include\GL\glx.h ..\include\GL\xmesa.h context.h

+glx.obj: types.h config.h fixed.h dd.h macros.h xmesaP.h

+osmesa.obj: ..\include\GL\osmesa.h ..\include\GL\gl.h context.h types.h

+osmesa.obj: config.h fixed.h dd.h depth.h macros.h matrix.h vb.h tritemp.h

+xfonts.obj: ..\include\GL\gl.h ..\include\GL\xmesa.h macros.h xmesaP.h types.h

+xfonts.obj: config.h fixed.h dd.h context.h

+xmesa1.obj: ..\include\GL\xmesa.h ..\include\GL\gl.h xmesaP.h types.h config.h

+xmesa1.obj: fixed.h dd.h context.h macros.h matrix.h

+xmesa2.obj: ..\include\GL\xmesa.h ..\include\GL\gl.h macros.h types.h config.h

+xmesa2.obj: fixed.h dd.h xmesaP.h

+xmesa3.obj: bresenhm.h types.h ..\include\GL\gl.h config.h fixed.h dd.h depth.h

+xmesa3.obj: interp.h macros.h vb.h xmesaP.h ..\include\GL\xmesa.h tritemp.h

diff --git a/src/mesa/drivers/dos/dosmesa.c b/src/mesa/drivers/dos/dosmesa.c
new file mode 100644
index 0000000000..2f3973284a
--- /dev/null
+++ b/src/mesa/drivers/dos/dosmesa.c
@@ -0,0 +1,1513 @@
+/* $Id: dosmesa.c,v 1.1 1999/08/19 00:55:41 jtg Exp $ */

+

+/*

+ * Mesa 3-D graphics library

+ * Version:  2.3

+ * Copyright (C) 1995-1997  Brian Paul

+ *

+ * This library is free software; you can redistribute it and/or

+ * modify it under the terms of the GNU Library General Public

+ * License as published by the Free Software Foundation; either

+ * version 2 of the License, or (at your option) any later version.

+ *

+ * This library 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

+ * Library General Public License for more details.

+ *

+ * You should have received a copy of the GNU Library General Public

+ * License along with this library; if not, write to the Free

+ * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

+ */

+

+

+/*

+ * $Log: dosmesa.c,v $
+ * Revision 1.1  1999/08/19 00:55:41  jtg
+ * Initial revision
+ *
+ * Revision 1.2  1999/03/28 21:11:57  brianp
+ * updated SetBuffer driver function
+ *
+ * Revision 1.1  1999/02/24 03:56:31  brianp
+ * initial check-in
+ *

+ *
+ * Revision 1.5  1997/06/19  22:00:00  Brian Paul

+ * Removed all ColorShift stuff
+ *

+ * Revision 1.4  1997/06/03  19:00:00  Brian Paul

+ * Replaced VB->Unclipped[] with VB->ClipMask[]

+ *

+ * Revision 1.3  1997/05/28  07:00:00  Phil Frisbie, Jr.

+ * Now pass red/green/blue/alpha bits to gl_create_visual()

+ * Fixed DJGPP mode 13 support.

+ *

+ * Revision 1.2  1996/12/08  16:13:45  Charlie

+ * Added VESA support via Scitechs SVGA kit.

+ *

+ * Revision 1.1  1996/12/08  16:09:52  Charlie

+ * Initial revision

+ *

+ */

+

+

+/*

+ * DOS VGA/VESA/MGL/Mesa interface.

+ *

+ */

+

+/*

+ *

+ * TODO: (cw)

+ *	 Improve the colour matcher for rgb non vesa modes, its pretty bad and incorrect

+ *	 Keyboard interrupt.

+ *  Comments and tidy up.

+ *  Add support for VESA without SVGAKIT.

+ *  DirectX Support.

+ *  Better GLIDE Support.

+ *  Clear up the #ifdef madness.

+ */

+

+#ifdef DOSVGA

+

+#if defined(DOSVGA) && !defined(GLIDE) && defined(DJGPP) && !defined(UNIVBE) && !defined(MGL)

+

+/* Should help cut down on the crazy #if`s */

+#define MODE13 1

+

+#else

+#undef MODE13

+#endif

+

+#include <stdio.h>

+#include <stdlib.h>

+#include <string.h>

+#include <string.h>

+#include <dos.h>

+

+#ifdef DJGPP

+#include <go32.h>

+#endif

+

+#ifdef MGL

+#include <mgraph.h>

+#endif

+

+#include "GL/DOSmesa.h"

+#include "context.h"

+#include "matrix.h"

+#include "types.h"

+

+#ifdef GLIDE

+

+static void glideshutdown( void );

+#include "vb.h"

+#include "glide.h"

+

+/* the glide modes available, set one */

+

+//#define GLIDE_MODE GR_RESOLUTION_

+#define GLIDE_MODE GR_RESOLUTION_800x600

+//#define GLIDE_MODE GR_RESOLUTION_640x480

+

+static GrVertex gr_vtx,gr_vtx1,gr_vtx2;

+

+#endif

+

+#ifdef UNIVBE

+/* You get this file from Scitechs VESA development kit */

+#include "svga.h"

+

+/*

+   Set these to the VESA mode you require, the first is for 256 colour modes,

+   the other is High colour modes, they must both be the same XRes and YRes.

+ */

+

+#define VESA_256COLOUR_MODE 0x11c

+#define VESA_HICOLOUR_MODE 0x11f

+

+#endif

+

+struct DOSmesa_context {

+   GLcontext *gl_ctx;			/* the core Mesa context */

+   GLvisual *gl_vis;				/* describes the color buffer */

+   GLframebuffer *gl_buffer;	/* the ancillary buffers */

+   GLuint index;					/* current color index */

+   GLint red, green, blue;		/* current rgb color */

+   GLint width, height;			/* size of color buffer */

+   GLint depth;					/* bits per pixel (8,16,24 or 32) */

+};

+

+static DOSMesaContext DOSMesa = NULL;    /* the current context */

+

+#ifdef UNIVBE

+SV_devCtx *DC=NULL;

+int useLinear = TRUE;

+SV_modeInfo *mi=NULL;

+unsigned long modeNumber = 0;

+

+int activePage = 0;

+int visualPage = 1;

+

+#endif

+

+#if defined(MODE13)

+

+/* DOSVGA With no UniVBE support */

+

+unsigned char *video_buffer;

+

+#define VID_BUF(x,y) *(video_buffer+x+(y*320))

+

+#if defined(__WATCOMC__) && defined(__386__) && defined(__DOS__)

+

+void setupcopy(void);

+void copyscr(void);

+

+/* Watcom C specfic, screen copy and clear */

+

+#pragma aux setupcopy = \

+	".386P"\

+	"push ebp" \

+	"mov esi,video_buffer" \

+	"mov edi,0xa0000" \

+	"mov ecx,2000" \

+	"xor ebp,ebp";

+

+#pragma aux copyscr = \

+	".386P" \

+	"lop1: mov eax,[esi]"\

+	"mov ebx,[esi+4]"\

+	"mov edx,[esi+8]"\

+	"mov [edi],eax"\

+	"mov eax,[esi+12]"\

+	"mov dword ptr [esi],ebp"\

+	"mov dword ptr [esi+4],ebp"\

+	"mov dword ptr [esi+8],ebp"\

+	"mov dword ptr [esi+12],ebp"\

+	"mov [edi+4],ebx"\

+	"mov [edi+8],edx"\

+	"mov [edi+12],eax"\

+	"mov eax,[esi+16]"\

+	"mov ebx,[esi+4+16]"\

+	"mov edx,[esi+8+16]"\

+	"mov [edi+16],eax"\

+	"mov eax,[esi+12+16]"\

+	"mov dword ptr [esi+16],ebp"\

+	"mov dword ptr [esi+4+16],ebp"\

+	"mov dword ptr [esi+8+16],ebp"\

+	"mov dword ptr [esi+12+16],ebp"\

+	"mov [edi+4+16],ebx"\

+	"mov [edi+8+16],edx"\

+	"mov [edi+12+16],eax"\

+	"add esi,32"\

+	"add edi,32"\

+	"dec ecx"\

+	"jnz lop1"\

+	"pop ebp"\

+	modify exact [edi esi eax ebx ecx] ;

+

+#endif // WATCOM

+

+#endif // MODE13

+

+/*

+ * Convert Mesa window Y coordinate to VGA screen Y coordinate:

+ */

+#define FLIP(Y)  (DOSMesa->height-(Y)-1)

+

+unsigned short vga_cindex = 32768 ;

+

+static points_func choose_points_function( void );

+static line_func choose_line_function( void );

+static triangle_func choose_polygon_function( void );

+static void fast_tri(GLcontext *ctx,GLuint v0, GLuint v1, GLuint v2, GLuint pv );

+

+static points_func choose_points_function( void )

+{

+	return NULL;

+}

+

+static line_func choose_line_function( void )

+{

+	return NULL;

+}

+

+static triangle_func choose_triangle_function( void )

+{

+	#if defined(MODE13)

+		return	NULL;

+	#endif

+

+	#if defined(GLIDE)

+		return fast_tri;

+	#endif

+

+	return	NULL;

+}

+

+

+#if defined(MODE13)

+

+void setgfxmode(void);

+void settextmode(void);

+

+#ifndef DJGPP

+#pragma aux setgfxmode = \

+	"mov	ax,13h" \

+	"int	10h" \

+	modify [eax];

+

+#pragma aux settextmode = \

+	"mov	ax,3h" \

+	"int	10h" \

+	modify [eax];

+#else

+void setgfxmode(void)

+{

+	union REGS in_regs,out_regs;

+

+	in_regs.x.ax = 0x13;

+	int386(0x10,&in_regs,&out_regs);

+}

+

+void settextmode(void)

+{

+	union REGS in_regs,out_regs;

+

+	in_regs.x.ax = 0x3;

+	int386(0x10,&in_regs,&out_regs);

+}

+

+#endif

+

+int set_video_mode(unsigned short x,unsigned short y,char mode)

+{

+	setgfxmode();

+	return 1;	/* likelyhood of this failing is very small */

+}

+

+void restore_video_mode(void)

+{

+	settextmode();

+}

+

+int vga_getcolors(void)

+{

+	return vga_cindex;

+}

+

+int vga_getxdim(void)

+{

+	return 320;

+}

+

+int vga_getydim(void)

+{

+	return 200;

+}

+

+static unsigned short num_rgb_alloc = 1; /* start from 1, zero is black */

+

+/* an unlikely colour */

+static unsigned char last_r=1,last_g=255,last_b=99;

+

+extern void set_onecolor(int index,int R,int G,int B);

+

+static unsigned char rgbtable[64][64][64];

+

+void vga_setrgbcolor(int r,int g,int b)

+{

+

+/*

+ * make this into a translation table

+ */

+

+	DOSMesa->red = r;

+	DOSMesa->green = g ;

+	DOSMesa->blue = b ;

+

+	r/=4; g/=4; b/=4;

+

+	if( (r == last_r) && (g == last_g) && (b == last_b) ) return;

+

+	last_r = r ;

+	last_g = g ;

+	last_b = b ;

+

+	if(r+g+b == 0 ) {

+		DOSMesa->index = 0 ;

+		return ;

+	}

+

+	if( rgbtable[r][g][b] == 0 ) {

+		/* not allocated yet */

+		if(num_rgb_alloc<256) {

+			DOSMesa->index = num_rgb_alloc;

+			set_onecolor(num_rgb_alloc,r,g,b);

+			rgbtable[r][g][b] = num_rgb_alloc;

+			num_rgb_alloc++;

+			return;

+

+		} else {

+			/* need to search for a close colour */

+			{

+				unsigned short pass ;

+

+				for(pass=0;pass<64;pass++) {

+					if(r-pass>0) {

+						if( rgbtable[r-pass][g][b] !=0 ) {

+							rgbtable[r][g][b] = rgbtable[r-pass][g][b];

+							DOSMesa->index = rgbtable[r-pass][g][b];

+							return;

+						}

+					}

+					if(r+pass<64) {

+						if( rgbtable[r+pass][g][b] !=0 ) {

+							rgbtable[r][g][b] = rgbtable[r+pass][g][b];

+							DOSMesa->index = rgbtable[r+pass][g][b];

+							return;

+						}

+					}

+				}

+			}

+			rgbtable[r][g][b] = rand()%255;

+		}

+	}

+	DOSMesa->index = rgbtable[r][g][b];

+}

+

+#if defined(DJGPP)

+static int dos_seg;

+#endif

+

+void vga_clear(void)

+{

+

+/* Check if we`re using watcom and DOS */

+#if defined(__WATCOMC__) && defined(__386__) && defined(__DOS__)

+	setupcopy();

+	copyscr();

+#else

+

+#if defined (DJGPP)

+

+

+	asm ("

+		pusha

+		pushw	%es

+

+		movw	_dos_seg, %es

+

+		movl	_video_buffer, %esi

+		movl	$0xa0000, %edi

+

+		movl	$64000, %ecx

+

+		rep	; movsb

+

+		popw	%es

+		popa

+	");

+

+#else

+

+	/* copy the RAM buffer to the Video memory */

+	memcpy((unsigned char *)0xa0000,video_buffer, vga_getxdim()*vga_getydim() );

+

+#endif //DJGPP

+

+	/* clear the RAM buffer */

+	memset(video_buffer,0, vga_getxdim()*vga_getydim() );

+

+#endif //WATCOMC

+

+}

+

+#ifndef DEBUG

+#define vga_drawpixel(x,y) { VID_BUF(x,y) = DOSMesa->index; }

+#else

+void vga_drawpixel(x,y)

+{

+	VID_BUF(x,y) = DOSMesa->index;

+}

+#endif

+

+int vga_getpixel(int x,int y)

+{

+	return 1;

+}

+

+void vga_flip(void)

+{

+

+}

+

+void vga_setcolor(int index)

+{

+	/* does something, what i`ve no idea */

+	DOSMesa->index = index;

+

+}

+

+#endif

+

+#if defined(UNIVBE)

+

+/* UniVBE VESA support */

+

+void set_video_mode(unsigned short x,unsigned short y,char mode)

+{

+	if( setup_vesa_mode(x,y,mode) == FALSE ) {

+		fprintf(stderr,"VESA: Set mode failed\n");

+		exit(1);

+	}

+}

+

+/*

+   This is problematic as we don`t know what resolution the user program

+   wants when we reach here. This is why the 256 colour and HiColour modes

+	should be the same resolution, perhaps i`ll make this an environment

+	variable

+ */

+

+

+void check_mi(void)

+{

+	if(mi!=0) return;

+

+	if(DC==NULL) {

+		DC = SV_init( TRUE );

+	}

+

+	if(modeNumber == 0 ) {

+		modeNumber = VESA_HICOLOUR_MODE;

+	}

+

+	SV_getModeInfo(modeNumber,mi);

+

+	return;

+}

+

+int setup_vesa_mode(short height,short width,short depth)

+{

+	if(DC==NULL) {

+		DC = SV_init( TRUE );

+		/* how many bits per pixel */

+		if( depth == 0)

+			modeNumber = VESA_256COLOUR_MODE;

+		else

+			modeNumber = VESA_HICOLOUR_MODE;

+	}

+

+	/* Check if correct VESA Version is available */

+	if( !DC || DC->VBEVersion < 0x0102) {

+		fprintf(stderr,"Require a VESA VBE version 1.2 or higher\n");

+		return FALSE;

+	}

+

+	/* Check for LFB Supprt */

+	if(DC->VBEVersion < 0x0200 ) {

+		useLinear = FALSE;

+	} else {

+		useLinear = TRUE ;

+	}

+

+ 	/* Get desired mode info */

+   if(!SV_getModeInfo( modeNumber, mi))

+		return FALSE;

+

+	/* Set VESA mode */

+	if(!SV_setMode(modeNumber | svMultiBuffer, FALSE, TRUE, mi->NumberOfPages) )

+		return FALSE;

+

+	return TRUE;

+}

+

+void restore_video_mode(void)

+{

+	SV_restoreMode();

+}

+

+void vga_clear(void)

+{

+	SV_clear(0);

+}

+

+void vga_flip(void)

+{

+	activePage = 1-activePage;

+	visualPage = 1-activePage;

+

+	SV_setActivePage(activePage);

+

+	/*

+	   Change false to true if you`re getting flickering

+	   even in double buffer mode, ( sets wait for Vertical retrace  )

+	*/

+	SV_setVisualPage(visualPage,false);

+}

+

+int vga_getcolors(void)

+{

+	check_mi();

+	switch ( mi->BitsPerPixel ) {

+		case 8:

+			return 256;

+		case 15:

+		case 16:

+			return 32768;

+		default:

+			return 64000;

+	 }

+}

+

+int vga_getxdim(void)

+{

+	check_mi();

+	return mi->XResolution;

+}

+

+int vga_getydim(void)

+{

+	check_mi();

+	return mi->YResolution;

+}

+

+unsigned long current_color = 255;

+

+void vga_setrgbcolor(int r,int g,int b)

+{

+	DOSMesa->red = r;

+	DOSMesa->green = g ;

+	DOSMesa->blue = b ;

+	current_color = SV_rgbColor(r,g,b);

+}

+

+void vga_setcolor(int index)

+{

+	DOSMesa->index = index;

+	current_color = index;

+}

+

+void vga_drawpixel(x,y)

+{

+	SV_putPixel(x,y,current_color);

+}

+

+/* TODO: */

+int vga_getpixel(x,y)

+{

+/*	return (int)SV_getPixel(x,y); */

+	fprintf(stderr,"vga_getpixel: Not implemented yet\n");

+	return 1;

+}

+

+/* End of UNIVBE section */

+#endif

+

+/* Scitechs MegaGraphicsLibrary http://www.scitechsoft.com/ */

+

+#if defined(MGL)

+

+/* MGL support */

+struct MI {

+	unsigned short BitsPerPixel;

+	unsigned long XResolution;

+	unsigned long YResolution;

+};

+

+struct MI*mi;

+

+static MGLDC*DC;

+static int activePage = 0;

+static int visualPage = 1;

+static int modeNumber = 0;

+

+void set_video_mode(unsigned short xres,unsigned short yres,char mode)

+{

+    int     i,driver = grDETECT,dmode = grDETECT;

+    event_t evt;

+

+	/* Start the MGL with only the SVGA 16m driver active */

+	MGL_registerDriver(MGL_SVGA16NAME,SVGA16_driver);

+	if (!MGL_init(&driver,&dmode,"..\\..\\"))

+		MGL_fatalError(MGL_errorMsg(MGL_result()));

+	if ((DC = MGL_createDisplayDC(false)) == NULL)

+		MGL_fatalError(MGL_errorMsg(MGL_result()));

+	MGL_makeCurrentDC(DC);

+}

+

+/*

+   This is problematic as we don`t know what resolution the user program

+   wants when we reach here. This is why the 256 colour and HiColour modes

+	should be the same resolution, perhaps i`ll make this an environment

+	variable

+ */

+

+#define MGL_HICOLOUR_MODE 0

+

+

+void check_mi(void)

+{

+	if(mi!=0) return;

+

+	if(DC==NULL) {

+//		DC = SV_init( TRUE );

+	}

+

+	if(modeNumber == 0 ) {

+		modeNumber = MGL_HICOLOUR_MODE;

+	}

+

+//	SV_getModeInfo(modeNumber,mi);

+

+	return;

+}

+

+void restore_video_mode(void)

+{

+	MGL_exit();

+}

+

+void vga_clear(void)

+{

+	MGL_clearDevice();

+}

+

+void vga_flip(void)

+{

+	activePage = 1-activePage;

+	visualPage = 1-activePage;

+

+//	SV_setActivePage(activePage);

+

+	/*

+	   Change false to true if you`re getting flickering

+	   even in double buffer mode, ( sets wait for Vertical retrace  )

+	*/

+//	SV_setVisualPage(visualPage,false);

+}

+

+int vga_getcolors(void)

+{

+	check_mi();

+	switch ( mi->BitsPerPixel ) {

+		case 8:

+			return 256;

+		case 15:

+		case 16:

+			return 32768;

+		default:

+			return 64000;

+	 }

+}

+

+int vga_getxdim(void)

+{

+	check_mi();

+	return mi->XResolution;

+}

+

+int vga_getydim(void)

+{

+	check_mi();

+	return mi->YResolution;

+}

+

+unsigned long current_color = 255;

+

+void vga_setrgbcolor(int r,int g,int b)

+{

+	DOSMesa->red = r;

+	DOSMesa->green = g ;

+	DOSMesa->blue = b ;

+	current_color = MGL_rgbColor(DC,r,g,b);

+}

+

+void vga_setcolor(int index)

+{

+	DOSMesa->index = index;

+	current_color = index;

+}

+

+void vga_drawpixel(x,y)

+{

+	MGL_pixelCoord(x,y);

+}

+

+/* TODO: */

+int vga_getpixel(x,y)

+{

+/*	return (int)SV_getPixel(x,y); */

+	fprintf(stderr,"vga_getpixel: Not implemented yet\n");

+	return 1;

+}

+

+/* End of UNIVBE section */

+#endif

+

+#ifdef GLIDE

+

+/* GLIDE support */

+

+static GrHwConfiguration hwconfig;

+

+void set_video_mode(unsigned short x,unsigned short y,char mode)

+{

+	grGlideInit();

+	if( grSstQueryHardware( &hwconfig ) ) {

+		grSstSelect( 0 ) ;

+		if( !grSstOpen( GLIDE_MODE,

+							GR_REFRESH_60Hz,

+							GR_COLORFORMAT_ABGR,

+							GR_ORIGIN_UPPER_LEFT,

+							GR_SMOOTHING_ENABLE,

+							2 ) ) {

+			fprintf(stderr,"Detected 3DFX board, but couldn`t initialize!");

+			exit(1);

+		}

+

+		grBufferClear( 0, 0, GR_WDEPTHVALUE_FARTHEST);

+

+		grDisableAllEffects();

+		atexit( glideshutdown );

+

+//		guColorCombineFunction( GR_COLORCOMBINE_ITRGB );

+//		grTexCombineFunction( GR_TMU0, GR_TEXTURECOMBINE_ZERO);

+	}

+}

+

+void restore_video_mode(void)

+{

+}

+

+static void glideshutdown( void )

+{

+	grGlideShutdown() ;

+}

+

+void vga_clear(void)

+{

+	grBufferSwap(0);

+	grBufferClear( 0, 0, GR_WDEPTHVALUE_FARTHEST);

+}

+

+void vga_flip(void)

+{

+}

+

+int vga_getcolors(void)

+{

+	return 32768;

+}

+

+int vga_getxdim(void)

+{

+#if GLIDE_MODE == GR_RESOLUTION_800x600

+		return 800;

+#else

+		return 640;

+#endif

+}

+

+int vga_getydim(void)

+{

+#if GLIDE_MODE == GR_RESOLUTION_800x600

+		return 600;

+#else

+		return 480;

+#endif

+}

+

+unsigned long current_color = 255;

+

+void vga_setrgbcolor(int r,int g,int b)

+{

+	DOSMesa->red = r;

+	DOSMesa->green = g ;

+	DOSMesa->blue = b ;

+}

+

+void vga_setcolor(int index)

+{

+	DOSMesa->index = index;

+}

+

+void vga_drawpixel(x,y)

+{

+

+	gr_vtx.x = x;

+	gr_vtx.y = y;

+	gr_vtx.z = 0;

+	gr_vtx.r	= DOSMesa->red;

+	gr_vtx.g	= DOSMesa->green;

+	gr_vtx.b	= DOSMesa->blue;

+

+	grDrawPoint( &gr_vtx );

+}

+

+static void fast_tri(GLcontext *ctx,GLuint v0, GLuint v1, GLuint v2, GLuint pv )

+{

+   struct vertex_buffer *VB = ctx->VB;

+

+	gr_vtx.z = 0;

+	gr_vtx1.z = 0;

+	gr_vtx2.z = 0;

+

+   if (VB->MonoColor) {

+	  	gr_vtx.r = DOSMesa->red;

+   	gr_vtx.g = DOSMesa->green;

+   	gr_vtx.b = DOSMesa->blue;

+   	gr_vtx1.r = DOSMesa->red;

+   	gr_vtx1.g = DOSMesa->green;

+   	gr_vtx1.b = DOSMesa->blue;

+   	gr_vtx2.r = DOSMesa->red;

+   	gr_vtx2.g = DOSMesa->green;

+   	gr_vtx2.b = DOSMesa->blue;

+   } else {

+		if(ctx->Light.ShadeModel == GL_SMOOTH ) {

+		  	gr_vtx.r  = FixedToInt( VB->Color[v0][0] );

+		  	gr_vtx.g  = FixedToInt( VB->Color[v0][1] );

+		  	gr_vtx.b  = FixedToInt( VB->Color[v0][2] );

+

+		  	gr_vtx1.r = FixedToInt( VB->Color[v1][0] );

+		  	gr_vtx1.g = FixedToInt( VB->Color[v1][1] );

+		  	gr_vtx1.b = FixedToInt( VB->Color[v1][2] );

+

+		  	gr_vtx2.r = FixedToInt( VB->Color[v2][0] );

+		  	gr_vtx2.g = FixedToInt( VB->Color[v2][1] );

+		  	gr_vtx2.b = FixedToInt( VB->Color[v2][2] );

+		} else {

+		  	gr_vtx.r  = VB->Color[pv][0];

+		  	gr_vtx.g  = VB->Color[pv][1];

+		  	gr_vtx.b  = VB->Color[pv][2];

+

+		  	gr_vtx1.r = VB->Color[pv][0];

+		  	gr_vtx1.g = VB->Color[pv][1];

+		  	gr_vtx1.b = VB->Color[pv][2];

+

+		  	gr_vtx2.r = VB->Color[pv][0];

+		  	gr_vtx2.g = VB->Color[pv][1];

+		  	gr_vtx2.b = VB->Color[pv][2];

+		}

+	}

+

+   gr_vtx.x  =       (VB->Win[v0][0] );

+   gr_vtx.y  = FLIP( (VB->Win[v0][1] ) );

+   gr_vtx1.x =       (VB->Win[v1][0] );

+   gr_vtx1.y = FLIP( (VB->Win[v1][1] ) );

+   gr_vtx2.x =       (VB->Win[v2][0] );

+   gr_vtx2.y = FLIP( (VB->Win[v2][1] ) );

+

+	if(gr_vtx.x <0 || gr_vtx.x > 639 )

+		return;

+	if(gr_vtx1.x <0 || gr_vtx1.x > 639 )

+		return;

+	if(gr_vtx2.x <0 || gr_vtx2.x > 639 )

+		return;

+

+	if(gr_vtx.y <0 || gr_vtx.y > 479 )

+		return;

+	if(gr_vtx1.y <0 || gr_vtx1.y > 479 )

+		return;

+	if(gr_vtx2.y <0 || gr_vtx2.y > 479 )

+		return;

+

+	grDrawTriangle( &gr_vtx,&gr_vtx1,&gr_vtx2);

+}

+

+void fast_plot(GLcontext *ctx,GLuint first,GLuint last )

+{

+	struct vertex_buffer *VB = ctx->VB;

+	register GLuint i;

+

+	if(VB->MonoColor) {

+		/* all same color */

+

+		gr_vtx.r = DOSMesa->red;

+		gr_vtx.g = DOSMesa->green;

+		gr_vtx.b = DOSMesa->blue;

+

+		for(i=first;i<last;i++) {

+			if(VB->ClipMask[i]==0) {

+				gr_vtx.x = VB->Win[i][0];

+				gr_vtx.y = FLIP(VB->Win[i][1]);

+			}

+		}

+	}

+}

+

+/* TODO: */

+int vga_getpixel(x,y)

+{

+/*	return (int)SV_getPixel(x,y); */

+	fprintf(stderr,"vga_getpixel: Not implemented yet\n");

+	return 1;

+}

+

+/* End of GLIDE section */

+

+#endif // GLIDE

+/**********************************************************************/

+/*****                 Miscellaneous functions                    *****/

+/**********************************************************************/

+

+

+static void get_buffer_size( GLcontext *ctx, GLuint *width, GLuint *height )

+{

+   *width = DOSMesa->width = vga_getxdim();

+   *height = DOSMesa->height = vga_getydim();

+}

+

+

+/* Set current color index */

+static void set_index( GLcontext *ctx, GLuint index )

+{

+   DOSMesa->index = index;

+   /*vga_setcolor( index );*/

+}

+

+

+/* Set current drawing color */

+static void set_color( GLcontext *ctx,

+                       GLubyte red, GLubyte green,

+                       GLubyte blue, GLubyte alpha )

+{

+   DOSMesa->red = red;

+   DOSMesa->green = green;

+   DOSMesa->blue = blue;

+   vga_setrgbcolor( red, green, blue );

+}

+

+

+static void clear_index( GLcontext *ctx, GLuint index )

+{

+   /* TODO: Implements glClearIndex() */

+}

+

+

+static void clear_color( GLcontext *ctx,

+                         GLubyte red, GLubyte green,

+                         GLubyte blue, GLubyte alpha )

+{

+   /* TODO: Implements glClearColor() */

+}

+

+

+static void clear( GLcontext *ctx,

+                   GLboolean all,

+                   GLint x, GLint y, GLint width, GLint height )

+{

+   vga_clear();

+}

+

+

+static GLboolean set_buffer( GLcontext *ctx,

+                             GLenum mode )

+{

+   /* TODO: implement double buffering and use this function to select */

+   /* between front and back buffers. */

+   if (buffer == GL_FRONT_LEFT)

+      return GL_TRUE;

+   else if (buffer == GL_BACK_LEFT)

+      return GL_TRUE;

+   else

+      return GL_FALSE;

+}

+

+

+

+

+/**********************************************************************/

+/*****            Write spans of pixels                           *****/

+/**********************************************************************/

+

+

+static void write_index_span( GLcontext *ctx,

+                              GLuint n, GLint x, GLint y,

+                              const GLuint index[],

+                              const GLubyte mask[] )

+{

+   int i;

+   y = FLIP(y);

+#ifdef UNIVBE

+	SV_beginPixel();

+#endif

+   for (i=0;i<n;i++,x++) {

+      if (mask[i]) {

+#ifdef UNIVBE

+		SV_putPixelFast(x,y,current_color);

+#else

+         vga_setcolor( index[i] );

+         vga_drawpixel( x, y );

+#endif

+      }

+   }

+

+#ifdef UNIVBE

+	SV_endPixel();

+#endif

+

+}

+

+

+

+static void write_monoindex_span( GLcontext *ctx,

+                                  GLuint n, GLint x, GLint y,

+                                  const GLubyte mask[] )

+{

+   int i;

+   y = FLIP(y);

+   /* use current color index */

+   vga_setcolor( DOSMesa->index );

+#ifdef UNIVBE

+	SV_beginPixel();

+#endif

+   for (i=0;i<n;i++,x++) {

+      if (mask[i]) {

+#ifdef UNIVBE

+			SV_putPixelFast(x,y,current_color);

+#else

+         vga_drawpixel( x, y );

+#endif

+      }

+   }

+#ifdef UNIVBE

+	SV_endPixel();

+#endif

+}

+

+

+

+static void write_color_span( GLcontext *ctx,

+                              GLuint n, GLint x, GLint y,

+                              const GLubyte red[], const GLubyte green[],

+                              const GLubyte blue[], const GLubyte alpha[],

+                              const GLubyte mask[] )

+{

+   int i;

+   y=FLIP(y);

+#ifdef UNIVBE

+	SV_beginPixel();

+#endif

+   if (mask) {

+      /* draw some pixels */

+      for (i=0; i<n; i++, x++) {

+         if (mask[i]) {

+#ifdef UNIVBE

+				SV_putPixelFast(x,y,SV_rgbColor(red[i], green[i], blue[i]) );

+#else

+            vga_setrgbcolor( red[i], green[i], blue[i] );

+            vga_drawpixel( x, y );

+#endif

+         }

+      }

+   }

+   else {

+      /* draw all pixels */

+      for (i=0; i<n; i++, x++) {

+#ifdef UNIVBE

+			SV_putPixelFast(x,y,SV_rgbColor(red[i], green[i], blue[i]) );

+#else

+         vga_setrgbcolor( red[i], green[i], blue[i] );

+         vga_drawpixel( x, y );

+#endif

+      }

+   }

+#ifdef UNIVBE

+	SV_endPixel();

+#endif

+}

+

+

+

+static void write_monocolor_span( GLcontext *ctx,

+                                  GLuint n, GLint x, GLint y,

+                                  const GLubyte mask[])

+{

+   int i;

+   y=FLIP(y);

+#ifdef UNIVBE

+	SV_beginPixel();

+#endif

+   /* use current rgb color */

+   vga_setrgbcolor( DOSMesa->red, DOSMesa->green, DOSMesa->blue );

+   for (i=0; i<n; i++, x++) {

+      if (mask[i]) {

+#ifdef UNIVBE

+			SV_putPixelFast(x,y,current_color);

+#else

+         vga_drawpixel( x, y );

+#endif

+      }

+   }

+#ifdef UNIVBE

+	SV_endPixel();

+#endif

+}

+

+

+

+/**********************************************************************/

+/*****                 Read spans of pixels                       *****/

+/**********************************************************************/

+

+

+static void read_index_span( GLcontext *ctx,

+                             GLuint n, GLint x, GLint y, GLuint index[])

+{

+   int i;

+   y = FLIP(y);

+   for (i=0; i<n; i++,x++) {

+      index[i] = vga_getpixel( x, y );

+   }

+}

+

+

+

+static void read_color_span( GLcontext *ctx,

+                             GLuint n, GLint x, GLint y,

+                             GLubyte red[], GLubyte green[],

+                             GLubyte blue[], GLubyte alpha[] )

+{

+   int i;

+   for (i=0; i<n; i++, x++) {

+      /* TODO */

+   }

+}

+

+

+

+/**********************************************************************/

+/*****                  Write arrays of pixels                    *****/

+/**********************************************************************/

+

+

+static void write_index_pixels( GLcontext *ctx,

+                                GLuint n, const GLint x[], const GLint y[],

+                                const GLuint index[], const GLubyte mask[] )

+{

+   int i;

+#ifdef UNIVBE

+	SV_beginPixel();

+#endif

+   for (i=0; i<n; i++) {

+      if (mask[i]) {

+#ifdef UNIVBE

+			SV_putPixelFast(x[i], FLIP(y[i]), index[i] );

+#else

+         vga_setcolor( index[i] );

+         vga_drawpixel( x[i], FLIP(y[i]) );

+#endif

+      }

+   }

+#ifdef UNIVBE

+	SV_endPixel();

+#endif

+}

+

+

+

+static void write_monoindex_pixels( GLcontext *ctx,

+                                    GLuint n,

+                                    const GLint x[], const GLint y[],

+                                    const GLubyte mask[] )

+{

+   int i;

+   /* use current color index */

+   vga_setcolor( DOSMesa->index );

+#ifdef UNIVBE

+	SV_beginPixel();

+#endif

+   for (i=0; i<n; i++) {

+      if (mask[i]) {

+#ifdef UNIVBE

+			SV_putPixelFast(x[i], FLIP(y[i]), DOSMesa->index);

+#else

+         vga_drawpixel( x[i], FLIP(y[i]) );

+#endif

+      }

+   }

+#ifdef UNIVBE

+	SV_endPixel();

+#endif

+}

+

+

+

+static void write_color_pixels( GLcontext *ctx,

+                                GLuint n, const GLint x[], const GLint y[],

+                                const GLubyte r[], const GLubyte g[],

+                                const GLubyte b[], const GLubyte a[],

+                                const GLubyte mask[] )

+{

+   int i;

+#ifdef UNIVBE

+	SV_beginPixel();

+#endif

+   for (i=0; i<n; i++) {

+      if (mask[i]) {

+#ifdef UNIVBE

+			SV_putPixelFast(x[i], FLIP(y[i]), SV_rgbColor(r[i], g[i], b[i]) );

+#else

+         vga_setrgbcolor( r[i], g[i], b[i] );

+         vga_drawpixel( x[i], FLIP(y[i]) );

+#endif

+      }

+   }

+#ifdef UNIVBE

+	SV_endPixel();

+#endif

+}

+

+static void write_monocolor_pixels( GLcontext *ctx,

+                                    GLuint n,

+                                    const GLint x[], const GLint y[],

+                                    const GLubyte mask[] )

+{

+   int i;

+   /* use current rgb color */

+   vga_setrgbcolor( DOSMesa->red, DOSMesa->green, DOSMesa->blue );

+#ifdef UNIVBE

+	SV_beginPixel();

+#endif

+   for (i=0; i<n; i++) {

+      if (mask[i]) {

+#ifdef UNIVBE

+			SV_putPixelFast(x[i], FLIP(y[i]), current_color );

+#else

+         vga_drawpixel( x[i], FLIP(y[i]) );

+#endif

+      }

+   }

+#ifdef UNIVBE

+	SV_endPixel();

+#endif

+}

+

+/**********************************************************************/

+/*****                   Read arrays of pixels                    *****/

+/**********************************************************************/

+

+/* Read an array of color index pixels. */

+static void read_index_pixels( GLcontext *ctx,

+                               GLuint n, const GLint x[], const GLint y[],

+                               GLuint index[], const GLubyte mask[] )

+{

+   int i;

+   for (i=0; i<n; i++) {

+      index[i] = vga_getpixel( x[i], FLIP(y[i]) );

+   }

+}

+

+

+

+static void read_color_pixels( GLcontext *ctx,

+                               GLuint n, const GLint x[], const GLint y[],

+                               GLubyte red[], GLubyte green[],

+                               GLubyte blue[], GLubyte alpha[],

+                               const GLubyte mask[] )

+{

+   /* TODO */

+}

+

+static void DOSmesa_setup_DD_pointers( GLcontext *ctx )

+{

+   /* Initialize all the pointers in the DD struct.  Do this whenever */

+   /* a new context is made current or we change buffers via set_buffer! */

+

+   ctx->Driver.UpdateState = DOSmesa_setup_DD_pointers;

+

+   ctx->Driver.ClearIndex = clear_index;

+   ctx->Driver.ClearColor = clear_color;

+   ctx->Driver.Clear = clear;

+

+   ctx->Driver.Index = set_index;

+   ctx->Driver.Color = set_color;

+

+   ctx->Driver.SetBuffer = set_buffer;

+   ctx->Driver.GetBufferSize = get_buffer_size;

+

+   ctx->Driver.PointsFunc = choose_points_function();

+   ctx->Driver.LineFunc = choose_line_function();

+   ctx->Driver.TriangleFunc = choose_triangle_function();

+

+

+   /* Pixel/span writing functions: */

+   /* TODO: use different funcs for 8, 16, 32-bit depths */

+   ctx->Driver.WriteColorSpan       = write_color_span;

+   ctx->Driver.WriteMonocolorSpan   = write_monocolor_span;

+   ctx->Driver.WriteColorPixels     = write_color_pixels;

+   ctx->Driver.WriteMonocolorPixels = write_monocolor_pixels;

+   ctx->Driver.WriteIndexSpan       = write_index_span;

+   ctx->Driver.WriteMonoindexSpan   = write_monoindex_span;

+   ctx->Driver.WriteIndexPixels     = write_index_pixels;

+   ctx->Driver.WriteMonoindexPixels = write_monoindex_pixels;

+

+   /* Pixel/span reading functions: */

+   /* TODO: use different funcs for 8, 16, 32-bit depths */

+   ctx->Driver.ReadIndexSpan = read_index_span;

+   ctx->Driver.ReadColorSpan = read_color_span;

+   ctx->Driver.ReadIndexPixels = read_index_pixels;

+   ctx->Driver.ReadColorPixels = read_color_pixels;

+}

+

+/*

+ * Create a new VGA/Mesa context and return a handle to it.

+ */

+DOSMesaContext DOSMesaCreateContext( void )

+{

+   DOSMesaContext ctx;

+   GLboolean rgb_flag;

+   GLfloat redscale, greenscale, bluescale, alphascale;

+   GLboolean db_flag = GL_FALSE;

+   GLboolean alpha_flag = GL_FALSE;

+   int colors;

+   GLint index_bits;

+   GLint redbits, greenbits, bluebits, alphabits;

+

+#if !defined(UNIVBE) && !defined(GLIDE) && !defined(MGL)

+	video_buffer = (unsigned char *) malloc( vga_getxdim() * vga_getydim() );

+

+	memset(video_buffer,0, vga_getxdim() * vga_getydim() );

+

+	memset(rgbtable,0,sizeof( rgbtable ) );

+#endif

+

+#if defined( DJGPP ) && !defined(UNIVBE) && !defined(GLIDE)

+	dos_seg = _go32_conventional_mem_selector();

+#endif

+

+   /* determine if we're in RGB or color index mode */

+   colors = vga_getcolors();

+   if (colors==32768) {

+      rgb_flag = GL_TRUE;

+      redscale = greenscale = bluescale = alphascale = 255.0;

+      redbits = greenbits = bluebits = 8;

+      alphabits = 0;

+      index_bits = 0;

+   }

+   else if (colors==256) {

+      rgb_flag = GL_FALSE;

+      redscale = greenscale = bluescale = alphascale = 0.0;

+      redbits = greenbits = bluebits = alphabits = 0;

+      index_bits = 8;

+   }

+   else {

+		restore_video_mode();

+      fprintf(stderr,"[%d] >16 bit color not implemented yet!\n",colors);

+      return NULL;

+   }

+

+   ctx = (DOSMesaContext) calloc( 1, sizeof(struct DOSmesa_context) );

+   if (!ctx) {

+      return NULL;

+   }

+

+   ctx->gl_vis = gl_create_visual( rgb_flag,

+                                   alpha_flag,

+                                   db_flag,

+                                   16,   /* depth_size */

+                                   8,    /* stencil_size */

+                                   16,   /* accum_size */

+                                   index_bits,

+                                   redscale,

+                                   greenscale,

+                                   bluescale,

+                                   alphascale,

+                                   redbits, greenbits,

+                                   bluebits, alphabits);

+

+   ctx->gl_ctx = gl_create_context( ctx->gl_vis,

+                                    NULL,  /* share list context */

+                                    (void *) ctx

+                                  );

+

+   ctx->gl_buffer = gl_create_framebuffer( ctx->gl_vis );

+

+   ctx->index = 1;

+   ctx->red = ctx->green = ctx->blue = 255;

+

+   ctx->width = ctx->height = 0;  /* temporary until first "make-current" */

+

+   return ctx;

+}

+

+/*

+ * Destroy the given VGA/Mesa context.

+ */

+void DOSMesaDestroyContext( DOSMesaContext ctx )

+{

+   if (ctx) {

+      gl_destroy_visual( ctx->gl_vis );

+      gl_destroy_context( ctx->gl_ctx );

+      gl_destroy_framebuffer( ctx->gl_buffer );

+      free( ctx );

+      if (ctx==DOSMesa) {

+         DOSMesa = NULL;

+      }

+   }

+}

+

+

+

+/*

+ * Make the specified VGA/Mesa context the current one.

+ */

+void DOSMesaMakeCurrent( DOSMesaContext ctx )

+{

+   DOSMesa = ctx;

+   gl_make_current( ctx->gl_ctx, ctx->gl_buffer );

+   DOSmesa_setup_DD_pointers( ctx->gl_ctx );

+

+   if (ctx->width==0 || ctx->height==0) {

+      /* setup initial viewport */

+      ctx->width = vga_getxdim();

+      ctx->height = vga_getydim();

+      gl_Viewport( ctx->gl_ctx, 0, 0, ctx->width, ctx->height );

+   }

+}

+

+

+

+/*

+ * Return a handle to the current VGA/Mesa context.

+ */

+DOSMesaContext DOSMesaGetCurrentContext( void )

+{

+   return DOSMesa;

+}

+

+

+/*

+ * Swap front/back buffers for current context if double buffered.

+ */

+void DOSMesaSwapBuffers( void )

+{

+#if !defined(UNIVBE)

+/* Assume double buffering is available if in UNIVBE,

+   if it isn`t its taken care of anyway */

+//   if (DOSMesa->gl_vis->DBflag)

+#endif

+ 	{

+      vga_flip();

+   }

+}

+

+

+#else

+

+/*

+ * Need this to provide at least one external definition when DOS is

+ * not defined on the compiler command line.

+ */

+

+int gl_DOS_dummy_function(void)

+{

+   return 0;

+}

+

+#endif  /*DOS*/

+