src/video/x11/SDL_x11modes.c
author Sunny Sachanandani <sunnysachanandani@gmail.com>
Fri, 09 Jul 2010 21:36:41 +0530
changeset 4590 1ad70fb49fcb
parent 3697 f7b03b6838cb
child 4591 1e998db9b597
permissions -rw-r--r--
Fix so many things that there is little place in this column to list them all but the result is that blending modes just work now for drawing primitives. Fixes involved: 1. Fix handling of alpha channel when SDL_BLENDMODE_NONE is set. 2. Make xrendercolor use floating-point values for color channels and then convert to 16 bit ints. 3. Fix handling of visuals in SDL_x11modes.c so that a 32 bit ARGB visual is used. 4. Fix the background pixel value in SDL_x11window.c so that the window background has an alpha value of 0xFF and not 0.

/*
    SDL - Simple DirectMedia Layer
    Copyright (C) 1997-2010 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"

#include "SDL_x11video.h"

#define X11MODES_DEBUG
#undef SDL_VIDEO_DRIVER_X11_XINERAMA
#undef SDL_VIDEO_DRIVER_X11_XRANDR
#undef SDL_VIDEO_DRIVER_X11_VIDMODE

static int
get_visualinfo(Display * display, int screen, XVisualInfo * vinfo)
{
    const char *visual_id = SDL_getenv("SDL_VIDEO_X11_VISUALID");
    int depth;
    XVisualInfo *vi;
    int nvis;

    /* Look for an exact visual, if requested */
    if (visual_id) {
        XVisualInfo template;

        SDL_zero(template);
        template.visualid = SDL_strtol(visual_id, NULL, 0);
        vi = XGetVisualInfo(display, VisualIDMask, &template, &nvis);
        if (vi) {
            *vinfo = *vi;
            XFree(vi);
            return 0;
        }
    }
#ifdef SDL_VIDEO_DRIVER_X11_XRENDER
    depth = 32;
    long vinfo_mask;
    XVisualInfo vinfo_templ;
    vinfo_mask = (VisualDepthMask | VisualRedMaskMask | VisualGreenMaskMask | VisualBlueMaskMask);
    vinfo_templ.depth = 32;
    vinfo_templ.red_mask = 0xFF0000;
    vinfo_templ.green_mask = 0xFF00;
    vinfo_templ.blue_mask = 0xFF;
    vi = XGetVisualInfo(display, vinfo_mask, &vinfo_templ, &nvis);
    if(vi) {
        *vinfo = *vi;
        XFree(vi);
        return 0;
    }
#endif
    depth = DefaultDepth(display, screen);
    if ((X11_UseDirectColorVisuals() &&
         XMatchVisualInfo(display, screen, depth, DirectColor, vinfo)) ||
        XMatchVisualInfo(display, screen, depth, TrueColor, vinfo) ||
        XMatchVisualInfo(display, screen, depth, PseudoColor, vinfo) ||
        XMatchVisualInfo(display, screen, depth, StaticColor, vinfo)) {
        return 0;
    }
    return -1;
}

static Uint32
X11_GetPixelFormatFromVisualInfo(Display * display, XVisualInfo * vinfo)
{
    if (vinfo->class == DirectColor || vinfo->class == TrueColor) {
        int bpp;
        Uint32 Rmask, Gmask, Bmask, Amask;

        Rmask = vinfo->visual->red_mask;
        Gmask = vinfo->visual->green_mask;
        Bmask = vinfo->visual->blue_mask;
        if (vinfo->depth == 32) {
            Amask = (0xFFFFFFFF & ~(Rmask | Gmask | Bmask));
        } else {
            Amask = 0;
        }

        bpp = vinfo->depth;
        if (bpp == 24) {
            int i, n;
            XPixmapFormatValues *p = XListPixmapFormats(display, &n);
            if (p) {
                for (i = 0; i < n; ++i) {
                    if (p[i].depth == 24) {
                        bpp = p[i].bits_per_pixel;
                        break;
                    }
                }
                XFree(p);
            }
        }

        return SDL_MasksToPixelFormatEnum(bpp, Rmask, Gmask, Bmask, Amask);
    }

    if (vinfo->class == PseudoColor || vinfo->class == StaticColor) {
        switch (vinfo->depth) {
        case 8:
            return SDL_PIXELTYPE_INDEX8;
        case 4:
            if (BitmapBitOrder(display) == LSBFirst) {
                return SDL_PIXELFORMAT_INDEX4LSB;
            } else {
                return SDL_PIXELFORMAT_INDEX4MSB;
            }
            break;
        case 1:
            if (BitmapBitOrder(display) == LSBFirst) {
                return SDL_PIXELFORMAT_INDEX1LSB;
            } else {
                return SDL_PIXELFORMAT_INDEX1MSB;
            }
            break;
        }
    }

    return SDL_PIXELFORMAT_UNKNOWN;
}

int
X11_InitModes(_THIS)
{
    SDL_VideoData *data = (SDL_VideoData *) _this->driverdata;
    int screen;

    for (screen = 0; screen < ScreenCount(data->display); ++screen) {
        XVisualInfo vinfo;
        SDL_VideoDisplay display;
        SDL_DisplayData *displaydata;
        SDL_DisplayMode mode;
        XPixmapFormatValues *pixmapFormats;
        int i, n;

        if (get_visualinfo(data->display, screen, &vinfo) < 0) {
            continue;
        }

        mode.format = X11_GetPixelFormatFromVisualInfo(data->display, &vinfo);
        mode.w = DisplayWidth(data->display, screen);
        mode.h = DisplayHeight(data->display, screen);
        mode.refresh_rate = 0;
        mode.driverdata = NULL;

        displaydata = (SDL_DisplayData *) SDL_malloc(sizeof(*displaydata));
        if (!displaydata) {
            continue;
        }
        displaydata->screen = screen;
        displaydata->visual = vinfo.visual;
        displaydata->depth = vinfo.depth;

        displaydata->scanline_pad = SDL_BYTESPERPIXEL(mode.format) * 8;
        pixmapFormats = XListPixmapFormats(data->display, &n);
        if (pixmapFormats) {
            for (i = 0; i < n; ++i) {
                if (pixmapFormats[i].depth == displaydata->depth) {
                    displaydata->scanline_pad = pixmapFormats[i].scanline_pad;
                    break;
                }
            }
            XFree(pixmapFormats);
        }

        SDL_zero(display);
        display.desktop_mode = mode;
        display.current_mode = mode;
        display.driverdata = displaydata;
        SDL_AddVideoDisplay(&display);
    }
    if (_this->num_displays == 0) {
        SDL_SetError("No available displays");
        return -1;
    }
    return 0;
}

/* Global for the error handler */
int vm_event, vm_error = -1;

#if SDL_VIDEO_DRIVER_X11_XINERAMA
static SDL_bool
CheckXinerama(Display * display, int *major, int *minor)
{
    const char *env;

    /* Default the extension not available */
    *major = *minor = 0;

    /* Allow environment override */
    env = getenv("SDL_VIDEO_X11_XINERAMA");
    if (env && !SDL_atoi(env)) {
        return SDL_FALSE;
    }

    /* Query the extension version */
    if (!SDL_NAME(XineramaQueryExtension) (display, major, minor) ||
        !SDL_NAME(XineramaIsActive) (display)) {
        return SDL_FALSE;
    }
    return SDL_TRUE;
}
#endif /* SDL_VIDEO_DRIVER_X11_XINERAMA */

#if SDL_VIDEO_DRIVER_X11_XRANDR
static SDL_bool
CheckXRandR(Display * display, int *major, int *minor)
{
    const char *env;

    /* Default the extension not available */
    *major = *minor = 0;

    /* Allow environment override */
    env = getenv("SDL_VIDEO_X11_XRANDR");
    if (env && !SDL_atoi(env)) {
        return SDL_FALSE;
    }

    if (!SDL_X11_HAVE_XRANDR) {
        return SDL_FALSE;
    }

    /* Query the extension version */
    if (!XRRQueryVersion(display, major, minor)) {
        return SDL_FALSE;
    }
    return SDL_TRUE;
}
#endif /* SDL_VIDEO_DRIVER_X11_XRANDR */

#if SDL_VIDEO_DRIVER_X11_VIDMODE
static SDL_bool
CheckVidMode(Display * display, int *major, int *minor)
{
    const char *env;

    /* Default the extension not available */
    *major = *minor = 0;

    /* Allow environment override */
    env = getenv("SDL_VIDEO_X11_VIDMODE");
    if (env && !SDL_atoi(env)) {
        return SDL_FALSE;
    }

    /* Query the extension version */
    vm_error = -1;
    if (!SDL_NAME(XF86VidModeQueryExtension) (display, &vm_event, &vm_error)
        || !SDL_NAME(XF86VidModeQueryVersion) (display, major, minor)) {
        return SDL_FALSE;
    }
    return SDL_TRUE;
}

Bool SDL_NAME(XF86VidModeGetModeInfo) (Display * dpy, int scr,
                                       SDL_NAME(XF86VidModeModeInfo) * info)
{
    Bool retval;
    int dotclock;
    SDL_NAME(XF86VidModeModeLine) l;
    SDL_zerop(info);
    SDL_zero(l);
    retval = SDL_NAME(XF86VidModeGetModeLine) (dpy, scr, &dotclock, &l);
    info->dotclock = dotclock;
    info->hdisplay = l.hdisplay;
    info->hsyncstart = l.hsyncstart;
    info->hsyncend = l.hsyncend;
    info->htotal = l.htotal;
    info->hskew = l.hskew;
    info->vdisplay = l.vdisplay;
    info->vsyncstart = l.vsyncstart;
    info->vsyncend = l.vsyncend;
    info->vtotal = l.vtotal;
    info->flags = l.flags;
    info->privsize = l.privsize;
    info->private = l.private;
    return retval;
}

static int
calculate_rate(SDL_NAME(XF86VidModeModeInfo) * info)
{
    return (info->htotal
            && info->vtotal) ? (1000 * info->dotclock / (info->htotal *
                                                         info->vtotal)) : 0;
}

static void
save_mode(Display * display, SDL_DisplayData * data)
{
    SDL_NAME(XF86VidModeGetModeInfo) (display, data->screen,
                                      &data->saved_mode);
    SDL_NAME(XF86VidModeGetViewPort) (display, data->screen,
                                      &data->saved_view.x,
                                      &data->saved_view.y);
}

static void
restore_mode(Display * display, SDL_DisplayData * data)
{
    SDL_NAME(XF86VidModeModeInfo) mode;

    if (SDL_NAME(XF86VidModeGetModeInfo) (display, data->screen, &mode)) {
        if (SDL_memcmp(&mode, &data->saved_mode, sizeof(mode)) != 0) {
            SDL_NAME(XF86VidModeSwitchToMode) (display, data->screen,
                                               &data->saved_mode);
        }
    }
    if ((data->saved_view.x != 0) || (data->saved_view.y != 0)) {
        SDL_NAME(XF86VidModeSetViewPort) (display, data->screen,
                                          data->saved_view.x,
                                          data->saved_view.y);
    }
}
#endif /* SDL_VIDEO_DRIVER_X11_VIDMODE */

void
X11_GetDisplayModes(_THIS, SDL_VideoDisplay * sdl_display)
{
    Display *display = ((SDL_VideoData *) _this->driverdata)->display;
    SDL_DisplayData *data = (SDL_DisplayData *) sdl_display->driverdata;
#if SDL_VIDEO_DRIVER_X11_XINERAMA
    int xinerama_major, xinerama_minor;
    int screens;
    SDL_NAME(XineramaScreenInfo) * xinerama;
#endif
#if SDL_VIDEO_DRIVER_X11_XRANDR
    int xrandr_major, xrandr_minor;
    int nsizes, nrates;
    XRRScreenSize *sizes;
    short *rates;
#endif
#if SDL_VIDEO_DRIVER_X11_VIDMODE
    int vm_major, vm_minor;
    int nmodes;
    SDL_NAME(XF86VidModeModeInfo) ** modes;
#endif
    int screen_w;
    int screen_h;
    SDL_DisplayMode mode;

    /* Unfortunately X11 requires the window to be created with the correct
     * visual and depth ahead of time, but the SDL API allows you to create
     * a window before setting the fullscreen display mode.  This means that
     * we have to use the same format for all windows and all display modes.
     * (or support recreating the window with a new visual behind the scenes)
     */
    mode.format = sdl_display->current_mode.format;
    mode.driverdata = NULL;

    data->use_xinerama = 0;
    data->use_xrandr = 0;
    data->use_vidmode = 0;
    screen_w = DisplayWidth(display, data->screen);
    screen_h = DisplayHeight(display, data->screen);

#if SDL_VIDEO_DRIVER_X11_XINERAMA
    /* Query Xinerama extention */
    if (CheckXinerama(display, &xinerama_major, &xinerama_minor)) {
#ifdef X11MODES_DEBUG
        printf("X11 detected Xinerama:\n");
#endif
        xinerama = SDL_NAME(XineramaQueryScreens) (display, &screens);
        if (xinerama) {
            int i;
            for (i = 0; i < screens; i++) {
#ifdef X11MODES_DEBUG
                printf("xinerama %d: %dx%d+%d+%d\n",
                       xinerama[i].screen_number,
                       xinerama[i].width, xinerama[i].height,
                       xinerama[i].x_org, xinerama[i].y_org);
#endif
                if (xinerama[i].screen_number == data->screen) {
                    data->use_xinerama =
                        xinerama_major * 100 + xinerama_minor;
                    data->xinerama_info = xinerama[i];
                }
            }
            XFree(xinerama);
        }

        if (data->use_xinerama) {
            /* Add the full xinerama mode */
            if (screen_w > data->xinerama_info.width ||
                screen_h > data->xinerama_info.height) {
                mode.w = screen_w;
                mode.h = screen_h;
                mode.refresh_rate = 0;
                SDL_AddDisplayMode(sdl_display, &mode);
            }

            /* Add the head xinerama mode */
            mode.w = data->xinerama_info.width;
            mode.h = data->xinerama_info.height;
            mode.refresh_rate = 0;
            SDL_AddDisplayMode(sdl_display, &mode);
        }
    }
#endif /* SDL_VIDEO_DRIVER_X11_XINERAMA */

#if SDL_VIDEO_DRIVER_X11_XRANDR
    /* XRandR */
    /* require at least XRandR v1.0 (arbitrary) */
    if (CheckXRandR(display, &xrandr_major, &xrandr_minor)
        && xrandr_major >= 1) {
#ifdef X11MODES_DEBUG
        fprintf(stderr, "XRANDR: XRRQueryVersion: V%d.%d\n",
                xrandr_major, xrandr_minor);
#endif

        /* save the screen configuration since we must reference it
           each time we toggle modes.
         */
        data->screen_config =
            XRRGetScreenInfo(display, RootWindow(display, data->screen));

        /* retrieve the list of resolution */
        sizes = XRRConfigSizes(data->screen_config, &nsizes);
        if (nsizes > 0) {
            int i, j;
            for (i = 0; i < nsizes; i++) {
                mode.w = sizes[i].width;
                mode.h = sizes[i].height;

                rates = XRRConfigRates(data->screen_config, i, &nrates);
                for (j = 0; j < nrates; ++j) {
                    mode.refresh_rate = rates[j];
#ifdef X11MODES_DEBUG
                    fprintf(stderr,
                            "XRANDR: mode = %4d[%d], w = %4d, h = %4d, rate = %4d\n",
                            i, j, mode.w, mode.h, mode.refresh_rate);
#endif
                    SDL_AddDisplayMode(sdl_display, &mode);
                }
            }

            data->use_xrandr = xrandr_major * 100 + xrandr_minor;
            data->saved_size =
                XRRConfigCurrentConfiguration(data->screen_config,
                                              &data->saved_rotation);
            data->saved_rate = XRRConfigCurrentRate(data->screen_config);
        }
    }
#endif /* SDL_VIDEO_DRIVER_X11_XRANDR */

#if SDL_VIDEO_DRIVER_X11_VIDMODE
    /* XVidMode */
    if (!data->use_xrandr &&
#if SDL_VIDEO_DRIVER_X11_XINERAMA
        (!data->use_xinerama || data->xinerama_info.screen_number == 0) &&
#endif
        CheckVidMode(display, &vm_major, &vm_minor) &&
        SDL_NAME(XF86VidModeGetAllModeLines) (display, data->screen, &nmodes,
                                              &modes)) {
        int i;

#ifdef X11MODES_DEBUG
        printf("VidMode modes: (unsorted)\n");
        for (i = 0; i < nmodes; ++i) {
            printf("Mode %d: %d x %d @ %d\n", i,
                   modes[i]->hdisplay, modes[i]->vdisplay,
                   calculate_rate(modes[i]));
        }
#endif
        for (i = 0; i < nmodes; ++i) {
            mode.w = modes[i]->hdisplay;
            mode.h = modes[i]->vdisplay;
            mode.refresh_rate = calculate_rate(modes[i]);
            SDL_AddDisplayMode(sdl_display, &mode);
        }
        XFree(modes);

        data->use_vidmode = vm_major * 100 + vm_minor;
        save_mode(display, data);
    }
#endif /* SDL_VIDEO_DRIVER_X11_VIDMODE */

    if (!data->use_xrandr && !data->use_vidmode) {
        mode.w = screen_w;
        mode.h = screen_h;
        mode.refresh_rate = 0;
        SDL_AddDisplayMode(sdl_display, &mode);
    }
#ifdef X11MODES_DEBUG
    if (data->use_xinerama) {
        printf("Xinerama is enabled\n");
    }

    if (data->use_xrandr) {
        printf("XRandR is enabled\n");
    }

    if (data->use_vidmode) {
        printf("VidMode is enabled\n");
    }
#endif /* X11MODES_DEBUG */
}

static void
get_real_resolution(Display * display, SDL_DisplayData * data, int *w, int *h,
                    int *rate)
{
#if SDL_VIDEO_DRIVER_X11_XRANDR
    if (data->use_xrandr) {
        int nsizes;
        XRRScreenSize *sizes;

        sizes = XRRConfigSizes(data->screen_config, &nsizes);
        if (nsizes > 0) {
            int cur_size;
            Rotation cur_rotation;

            cur_size =
                XRRConfigCurrentConfiguration(data->screen_config,
                                              &cur_rotation);
            *w = sizes[cur_size].width;
            *h = sizes[cur_size].height;
            *rate = XRRConfigCurrentRate(data->screen_config);
#ifdef X11MODES_DEBUG
            fprintf(stderr,
                    "XRANDR: get_real_resolution: w = %d, h = %d, rate = %d\n",
                    *w, *h, *rate);
#endif
            return;
        }
    }
#endif /* SDL_VIDEO_DRIVER_X11_XRANDR */

#if SDL_VIDEO_DRIVER_X11_VIDMODE
    if (data->use_vidmode) {
        SDL_NAME(XF86VidModeModeInfo) mode;

        if (SDL_NAME(XF86VidModeGetModeInfo) (display, data->screen, &mode)) {
            *w = mode.hdisplay;
            *h = mode.vdisplay;
            *rate = calculate_rate(&mode);
            return;
        }
    }
#endif /* SDL_VIDEO_DRIVER_X11_VIDMODE */

#if SDL_VIDEO_DRIVER_X11_XINERAMA
    if (data->use_xinerama) {
        *w = data->xinerama_info.width;
        *h = data->xinerama_info.height;
        *rate = 0;
        return;
    }
#endif /* SDL_VIDEO_DRIVER_X11_XINERAMA */

    *w = DisplayWidth(display, data->screen);
    *h = DisplayHeight(display, data->screen);
    *rate = 0;
}

static void
set_best_resolution(Display * display, SDL_DisplayData * data, int w, int h,
                    int rate)
{
    int real_w, real_h, real_rate;

    /* check current mode so we can avoid uneccessary mode changes */
    get_real_resolution(display, data, &real_w, &real_h, &real_rate);
    if (w == real_w && h == real_h && (!rate || rate == real_rate)) {
        return;
    }
#if SDL_VIDEO_DRIVER_X11_XRANDR
    if (data->use_xrandr) {
#ifdef X11MODES_DEBUG
        fprintf(stderr, "XRANDR: set_best_resolution(): w = %d, h = %d\n",
                w, h);
#endif
        int i, nsizes, nrates;
        int best;
        int best_rate;
        XRRScreenSize *sizes;
        short *rates;

        /* find the smallest resolution that is at least as big as the user requested */
        best = -1;
        sizes = XRRConfigSizes(data->screen_config, &nsizes);
        for (i = 0; i < nsizes; ++i) {
            if (sizes[i].width < w || sizes[i].height < h) {
                continue;
            }
            if (sizes[i].width == w && sizes[i].height == h) {
                best = i;
                break;
            }
            if (best == -1 ||
                (sizes[i].width < sizes[best].width) ||
                (sizes[i].width == sizes[best].width
                 && sizes[i].height < sizes[best].height)) {
                best = i;
            }
        }

        if (best >= 0) {
            best_rate = 0;
            rates = XRRConfigRates(data->screen_config, best, &nrates);
            for (i = 0; i < nrates; ++i) {
                if (rates[i] == rate) {
                    best_rate = rate;
                    break;
                }
                if (!rate) {
                    /* Higher is better, right? */
                    if (rates[i] > best_rate) {
                        best_rate = rates[i];
                    }
                } else {
                    if (SDL_abs(rates[i] - rate) < SDL_abs(best_rate - rate)) {
                        best_rate = rates[i];
                    }
                }
            }
            XRRSetScreenConfigAndRate(display, data->screen_config,
                                      RootWindow(display, data->screen), best,
                                      data->saved_rotation, best_rate,
                                      CurrentTime);
        }
        return;
    }
#endif /* SDL_VIDEO_DRIVER_X11_XRANDR */

#if SDL_VIDEO_DRIVER_X11_VIDMODE
    if (data->use_vidmode) {
        SDL_NAME(XF86VidModeModeInfo) ** modes;
        int i, nmodes;
        int best;

        if (SDL_NAME(XF86VidModeGetAllModeLines)
            (display, data->screen, &nmodes, &modes)) {
            best = -1;
            for (i = 0; i < nmodes; ++i) {
                if (modes[i]->hdisplay < w || modes[i]->vdisplay < h) {
                    continue;
                }
                if (best == -1 ||
                    (modes[i]->hdisplay < modes[best]->hdisplay) ||
                    (modes[i]->hdisplay == modes[best]->hdisplay
                     && modes[i]->vdisplay < modes[best]->vdisplay)) {
                    best = i;
                    continue;
                }
                if ((modes[i]->hdisplay == modes[best]->hdisplay) &&
                    (modes[i]->vdisplay == modes[best]->vdisplay)) {
                    if (!rate) {
                        /* Higher is better, right? */
                        if (calculate_rate(modes[i]) >
                            calculate_rate(modes[best])) {
                            best = i;
                        }
                    } else {
                        if (SDL_abs(calculate_rate(modes[i]) - rate) <
                            SDL_abs(calculate_rate(modes[best]) - rate)) {
                            best = i;
                        }
                    }
                }
            }
            if (best >= 0) {
#ifdef X11MODES_DEBUG
                printf("Best Mode %d: %d x %d @ %d\n", best,
                       modes[best]->hdisplay, modes[best]->vdisplay,
                       calculate_rate(modes[best]));
#endif
                SDL_NAME(XF86VidModeSwitchToMode) (display, data->screen,
                                                   modes[best]);
            }
            XFree(modes);
        }
        return;
    }
#endif /* SDL_VIDEO_DRIVER_X11_VIDMODE */
}

int
X11_SetDisplayMode(_THIS, SDL_VideoDisplay * sdl_display, SDL_DisplayMode * mode)
{
    Display *display = ((SDL_VideoData *) _this->driverdata)->display;
    SDL_DisplayData *data = (SDL_DisplayData *) sdl_display->driverdata;

    set_best_resolution(display, data, mode->w, mode->h, mode->refresh_rate);
    return 0;
}

void
X11_QuitModes(_THIS)
{
}

/* vi: set ts=4 sw=4 expandtab: */