Save/restore current video mode and palette

--HG--
extra : convert_revision : svn%3Ac70aab31-4412-0410-b14c-859654838e24/trunk%402233

src/video/xbios/SDL_xbios.c

@@ -174,7 +174,7 @@ XBIOS_VideoInit(_THIS)
 {
     /* Save screensaver settings */
 
-    /* Init video mode list */
+    /* Init video mode list, save current video mode settings */
     SDL_XBIOS_InitModes(_this);
 
     return (0);
@@ -187,5 +187,6 @@ XBIOS_VideoQuit(_THIS)
 
     /* Restore screensaver settings */
 
+    /* Restore previous video mode settings */
     SDL_XBIOS_QuitModes(_this);
 }

src/video/xbios/SDL_xbios.h

@@ -29,7 +29,12 @@
 
 typedef struct SDL_VideoData
 {
-    long cookie_vdo;
+    long cookie_vdo;		/* _VDO cookie */
+
+    Uint16 old_modecode;	/* Current video mode */
+    void *old_vbase;		/* Current pointer to video RAM */
+    int old_numcol;		/* Number of colors in saved palette */
+    Uint32 old_palette[256];	/* Buffer to save current palette */
 
 #if 0
     int old_video_mode;         /* Old video mode before entering SDL */

src/video/xbios/SDL_xbiosmodes.c

@@ -105,11 +105,146 @@ SDL_XBIOS_AddMode(_THIS, int width, int height, int bpp, Uint16 modecode,
     SDL_AddVideoDisplay(&display);
 }
 
+/* Current video mode save/restore */
+
+static void
+SDL_XBIOS_ModeSave(_THIS)
+{
+    SDL_VideoData *data = (SDL_VideoData *) _this->driverdata;
+
+    data->old_vbase = Physbase();
+
+    switch (data->cookie_vdo >> 16) {
+    case VDO_ST:
+    case VDO_STE:
+        data->old_modecode = Getrez();
+        break;
+    case VDO_TT:
+        data->old_modecode = EgetShift();
+        break;
+    case VDO_F30:
+        data->old_modecode = VsetMode(-1);
+        break;
+    }
+}
+
+static void
+SDL_XBIOS_ModeRestore(_THIS)
+{
+    SDL_VideoData *data = (SDL_VideoData *) _this->driverdata;
+
+    switch (data->cookie_vdo >> 16) {
+    case VDO_ST:
+    case VDO_STE:
+        Setscreen(-1, data->old_vbase, data->old_modecode);
+        break;
+    case VDO_TT:
+        Setscreen(-1, data->old_vbase, -1);
+	EsetShift(data->old_modecode);
+        break;
+    case VDO_F30:
+        Setscreen(-1, data->old_vbase, -1);
+        VsetMode(data->old_modecode);
+        break;
+    }
+}
+
+/* Current palette save/restore */
+
+static void
+SDL_XBIOS_PaletteSave(_THIS)
+{
+    int i;
+    Uint16 *palette;
+    SDL_VideoData *data = (SDL_VideoData *) _this->driverdata;
+
+    data->old_numcol = 0;
+
+    switch (data->cookie_vdo >> 16) {
+    case VDO_ST:
+    case VDO_STE:
+        switch (data->old_modecode << 8) {
+        case ST_LOW:
+            data->old_numcol = 16;
+            break;
+        case ST_MED:
+            data->old_numcol = 4;
+            break;
+        case ST_HIGH:
+            data->old_numcol = 2;
+            break;
+        }
+
+        palette = (Uint16 *) data->old_palette;
+        for (i = 0; i < data->old_numcol; i++) {
+            *palette++ = Setcolor(i, -1);
+        }
+        break;
+    case VDO_TT:
+        switch (data->old_modecode & ES_MODE) {
+        case TT_LOW:
+            data->old_numcol = 256;
+            break;
+        case ST_LOW:
+        case TT_MED:
+            data->old_numcol = 16;
+            break;
+        case ST_MED:
+            data->old_numcol = 4;
+            break;
+        case ST_HIGH:
+        case TT_HIGH:
+            data->old_numcol = 2;
+            break;
+        }
+        if (data->old_numcol) {
+            EgetPalette(0, data->old_numcol, data->old_palette);
+        }
+        break;
+    case VDO_F30:
+        data->old_numcol = 1 << (1 << (data->old_modecode & NUMCOLS));
+        if (data->old_numcol > 256) {
+	    data->old_numcol = 0;
+	} else {
+            VgetRGB(0, data->old_numcol, data->old_palette);
+        }
+        break;
+    }
+}
+
+static void
+SDL_XBIOS_PaletteRestore(_THIS)
+{
+    SDL_VideoData *data = (SDL_VideoData *) _this->driverdata;
+
+    if (data->old_numcol == 0) {
+        return;
+    }
+
+    switch (data->cookie_vdo >> 16) {
+    case VDO_ST:
+    case VDO_STE:
+        Setpalette(data->old_palette);
+        break;
+    case VDO_TT:
+        EsetPalette(0, data->old_numcol, data->old_palette);
+        break;
+    case VDO_F30:
+        VsetRGB(0, data->old_numcol, data->old_palette);
+        break;
+    }
+}
+
+/* Public functions for use by the driver */
+
 void
 SDL_XBIOS_InitModes(_THIS)
 {
     SDL_VideoData *data = (SDL_VideoData *) _this->driverdata;
 
+    SDL_XBIOS_PaletteSave(_this);
+    SDL_XBIOS_ModeSave(_this);
+
     switch (data->cookie_vdo >> 16) {
     case VDO_ST:
     case VDO_STE:
@@ -126,7 +261,7 @@ SDL_XBIOS_InitModes(_THIS)
         break;
     case VDO_F30:
         {
-	    Uint16 modecodemask = VsetMode(-1) & (VGA | PAL);
+	    Uint16 modecodemask = data->old_modecode & (VGA | PAL);
             int i;
 
             switch (VgetMonitor()) {
@@ -172,6 +307,9 @@ SDL_XBIOS_SetDisplayMode(_THIS, SDL_DisplayMode * mode)
 void
 SDL_XBIOS_QuitModes(_THIS)
 {
+    SDL_XBIOS_ModeRestore(_this);
+    SDL_XBIOS_PaletteRestore(_this);
+    Vsync();
 }
 
 /* vi: set ts=4 sw=4 expandtab: */

src/video/xbios/SDL_xbiosmodes.h

@@ -0,0 +1,41 @@
+/*
+    SDL - Simple DirectMedia Layer
+    Copyright (C) 1997-2006 Sam Lantinga
+
+    This library is free software; you can redistribute it and/or
+    modify it under the terms of the GNU Lesser General Public
+    License as published by the Free Software Foundation; either
+    version 2.1 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
+    Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public
+    License along with this library; if not, write to the Free Software
+    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+    Sam Lantinga
+    slouken@libsdl.org
+*/
+#include "SDL_config.h"
+
+#ifndef _SDL_xbiosmodes_h
+#define _SDL_xbiosmodes_h
+
+typedef struct
+{
+    Uint16 modecode;
+    SDL_bool doubleline;
+    SDL_bool c2p4;
+} SDL_DisplayData;
+
+extern void SDL_XBIOS_InitModes(_THIS);
+extern void SDL_XBIOS_GetDisplayModes(_THIS);
+extern int SDL_XBIOS_SetDisplayMode(_THIS, SDL_DisplayMode * mode);
+extern void SDL_XBIOS_QuitModes(_THIS);
+
+#endif /* _SDL_xbiosmodes_h */
+
+/* vi: set ts=4 sw=4 expandtab: */