view src/video/xbios/SDL_xbios.h @ 2752:edd2839b36f7

http://sources.redhat.com/ml/newlib/2002/msg00230.html Stephen L Moshier wrote: > > pow(x,y) returns 0 when x is very close to -1.0 and y is very large. > The following test program prints > > pow(1.0000000000000002e+00 4.5035996273704970e+15) = 2.7182818284590455e+00 > pow(-1.0000000000000002e+00 4.5035996273704970e+15) =0.0000000000000000e+00 > pow(9.9999999999999978e-01 4.5035996273704970e+15) = 3.6787944117144222e-01 > pow(-9.9999999999999978e-01 4.5035996273704970e+15) = 0.0000000000000000e+00 > > which is incorrect for the negative arguments raised to an odd integer > power. > > ----- > double pow (double, double); > > int > main () > { > double x, y, z; > > x = 1.0 + pow (2.0, -52.0); > y = 1.0 + pow (2.0, 52.0); > z = pow (x, y); > printf ("pow(%.16e %.16e) = %.16e\n", x, y, z); > x = -x; > z = pow (x, y); > printf ("pow(%.16e %.16e) = %.16e\n", x, y, z); > x = 1.0 - pow (2.0, -52.0); > z = pow (x, y); > printf ("pow(%.16e %.16e) = %.16e\n", x, y, z); > x = -x; > z = pow (x, y); > printf ("pow(%.16e %.16e) = %.16e\n", x, y, z); > } > ----- > > Here is a patch for newlib/libm/math/epow.c: Patch checked in and duplicated for ef_pow.c. Thanks. -- Jeff J.
author Sam Lantinga <slouken@libsdl.org>
date Mon, 15 Sep 2008 04:31:30 +0000
parents 2c835d58faad
children 99210400e8b9
line wrap: on
line source

/*
    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_xbios_h
#define _SDL_xbios_h

#include "SDL_stdinc.h"
#include "../SDL_sysvideo.h"

typedef struct SDL_VideoData
{
    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 */
    void *old_video_base;       /* Old pointer to screen buffer */
    void *old_palette;          /* Old palette */
    Uint32 old_num_colors;      /* Nb of colors in saved palette */
    int num_modes;              /* Number of xbios video modes */
    xbiosmode_t *mode_list;     /* List of xbios video modes */

    void *screens[2];           /* Pointers to aligned screen buffer */
    void *screensmem[2];        /* Pointers to screen buffer */
    void *shadowscreen;         /* Shadow screen for c2p conversion */
    int doubleline;             /* Double line mode ? */
    int frame_number;           /* Number of frame for double buffer */
    int pitch;                  /* Destination line width for C2P */
    int width, height;          /* Screen size for centered C2P */

    SDL_bool centscreen;        /* Centscreen extension present ? */

    SDL_Rect *SDL_modelist[NUM_MODELISTS][SDL_NUMMODES + 1];
    xbiosmode_t *videomodes[NUM_MODELISTS][SDL_NUMMODES + 1];
#endif
} SDL_VideoData;

/* _VDO cookie values */
enum
{
    VDO_ST = 0,
    VDO_STE,
    VDO_TT,
    VDO_F30
};

/* Monitor types */
enum
{
    MONITOR_MONO = 0,
    MONITOR_TV,
    MONITOR_VGA,
    MONITOR_RGB
};

/* EgetShift masks */
#define ES_BANK		0x000f
#define ES_MODE		0x0700
#define ES_GRAY		0x1000
#define ES_SMEAR	0x8000

/* TT shifter modes */
#define ST_LOW	0x0000
#define ST_MED	0x0100
#define ST_HIGH	0x0200
#define TT_LOW	0x0700
#define TT_MED	0x0300
#define TT_HIGH	0x0600

#endif /* _SDL_xbios_h */
/* vi: set ts=4 sw=4 expandtab: */