Date: Sun, 23 Oct 2005 16:39:03 +0200
From: "A. Schmid" <sahib@phreaker.net>
To: sdl@libsdl.org
Subject: [SDL] no software surfaces with svgalib driver?

--- src/video/svga.orig/SDL_svgavideo.c	2004-01-04 17:49:26.000000000 +0100
+++ src/video/svga/SDL_svgavideo.c	2005-09-29 22:39:30.000000000 +0200
@@ -46,6 +46,7 @@
 #include <vga.h>
 #include <vgamouse.h>
 #include <vgakeyboard.h>
+#include <vgagl.h>
 
 #include "SDL.h"
 #include "SDL_error.h"
@@ -59,6 +60,9 @@
 #include "SDL_svgamouse_c.h"
 
 
+#include <string.h>
+static GraphicsContext *realgc, *virtgc=NULL;
+
 /* Initialization/Query functions */
 static int SVGA_VideoInit(_THIS, SDL_PixelFormat *vformat);
 static SDL_Rect **SVGA_ListModes(_THIS, SDL_PixelFormat *format, Uint32 flags);
@@ -176,7 +180,7 @@
 		int i, j;
 
 		i = modeinfo->bytesperpixel-1;
-		if ( actually_add ) {
+		if (( actually_add ) && (i >= 0)) {
 			SDL_Rect saved_rect[2];
 			int      saved_mode[2];
 			int b;
@@ -223,7 +228,7 @@
 	vga_modeinfo *modeinfo;
 
 	this->info.wm_available = 0;
-	this->info.hw_available = 1;
+	this->info.hw_available = ((virtgc==NULL) ? 1 : 0);
 	modeinfo = vga_getmodeinfo(vga_getcurrentmode());
 	this->info.video_mem = modeinfo->memory;
 	/* FIXME: Add hardware accelerated blit information */
@@ -246,7 +251,7 @@
 	}
 
 	/* Initialize the library */
-	vga_disabledriverreport();
+//	vga_disabledriverreport(); // why disable it?
 	if ( vga_init() < 0 ) {
 		SDL_SetError("Unable to initialize SVGAlib");
 		return(-1);
@@ -272,7 +277,7 @@
 	total_modes = 0;
 	for ( mode=vga_lastmodenumber(); mode; --mode ) {
 		if ( vga_hasmode(mode) ) {
-			if ( SVGA_AddMode(this, mode, 0, 0) ) {
+			if ( SVGA_AddMode(this, mode, 0, 1) ) {
 				++total_modes;
 			}
 		}
@@ -306,7 +311,7 @@
 	}
 	for ( mode=vga_lastmodenumber(); mode; --mode ) {
 		if ( vga_hasmode(mode) ) {
-			SVGA_AddMode(this, mode, 1, 0);
+			SVGA_AddMode(this, mode, 1, 1);
 		}
 	}
 	SVGA_AddMode(this, G320x200x256, 1, 1);
@@ -365,9 +370,25 @@
 
 	vgamode=SDL_vgamode[bpp][mode];
 	if ((vga_setlinearaddressing()<0) && (vgamode!=G320x200x256)) {
-		SDL_SetError("Unable to set linear addressing");
-		return(NULL);
+    
+    gl_setcontextvga(SDL_vgamode[bpp][mode]);
+    realgc = gl_allocatecontext();
+    gl_getcontext(realgc);
+    
+    gl_setcontextvgavirtual(SDL_vgamode[bpp][mode]);
+    virtgc = gl_allocatecontext();
+    gl_getcontext(virtgc);
+    
+    current->flags = (SDL_FULLSCREEN|SDL_SWSURFACE);
+    flags &= ~SDL_DOUBLEBUF;
+    current->flags &= ~SDL_DOUBLEBUF;
+    current->pixels = virtgc->vbuf;
+//		return(NULL);
+	} else {
+    current->flags = (SDL_FULLSCREEN|SDL_HWSURFACE);
+    current->pixels = vga_getgraphmem();
 	}
+    
 	modeinfo = vga_getmodeinfo(SDL_vgamode[bpp][mode]);
 
 	/* Update hardware acceleration info */
@@ -383,7 +404,7 @@
 	}
 
 	/* Set up the new mode framebuffer */
-	current->flags = (SDL_FULLSCREEN|SDL_HWSURFACE);
+//	current->flags = (SDL_FULLSCREEN|SDL_HWSURFACE);
 	if ( bpp == 8 ) {
 		/* FIXME: What about DirectColor? */
 		current->flags |= SDL_HWPALETTE;
@@ -391,7 +412,7 @@
 	current->w = width;
 	current->h = height;
 	current->pitch = modeinfo->linewidth;
-	current->pixels = vga_getgraphmem();
+//	current->pixels = vga_getgraphmem();
 
 	/* set double-buffering */
 	if ( flags & SDL_DOUBLEBUF )
@@ -454,6 +475,7 @@
 
 static int SVGA_FlipHWSurface(_THIS, SDL_Surface *surface)
 {
+  if (virtgc!=NULL) return 0; // for SWSURFACE. don't know who calls this...
 	vga_setdisplaystart(flip_offset[flip_page]);
 	flip_page=!flip_page;
 	surface->pixels=flip_address[flip_page];
@@ -463,6 +485,18 @@
 
 static void SVGA_DirectUpdate(_THIS, int numrects, SDL_Rect *rects)
 {
+  if (virtgc==NULL) return; // HWSURFACE then, already there :)
+
+	int i;
+	SDL_Rect *rect;
+
+//  vga_waitretrace();
+	for ( i=0; i < numrects; ++i ) {
+		rect = &rects[i];
+    // copy from virtgc to realgc
+    gl_copyboxtocontext(rect->x, rect->y, rect->w, rect->h, realgc, rect->x, rect->y);
+	}
+
 	return;
 }
 
@@ -492,6 +526,8 @@
 {
 	int i, j;
 
+//  if (virtgc!=NULL) { gl_freecontext(virtgc); virtgc=NULL; }; // hmmm... perhaps better not?
+
 	/* Reset the console video mode */
 	if ( this->screen && (this->screen->w && this->screen->h) ) {
 		vga_setmode(TEXT);