TinyX/render/filter.c

/*
 *
 * Copyright © 2002 Keith Packard
 *
 * Permission to use, copy, modify, distribute, and sell this software and its
 * documentation for any purpose is hereby granted without fee, provided that
 * the above copyright notice appear in all copies and that both that
 * copyright notice and this permission notice appear in supporting
 * documentation, and that the name of Keith Packard not be used in
 * advertising or publicity pertaining to distribution of the software without
 * specific, written prior permission.  Keith Packard makes no
 * representations about the suitability of this software for any purpose.  It
 * is provided "as is" without express or implied warranty.
 *
 * KEITH PACKARD DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
 * EVENT SHALL KEITH PACKARD BE LIABLE FOR ANY SPECIAL, INDIRECT OR
 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
 * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
 * PERFORMANCE OF THIS SOFTWARE.
 */

#ifdef HAVE_DIX_CONFIG_H
#include <dix-config.h>
#endif

#include "misc.h"
#include "scrnintstr.h"
#include "os.h"
#include "regionstr.h"
#include "validate.h"
#include "windowstr.h"
#include "input.h"
#include "resource.h"
#include "colormapst.h"
#include "cursorstr.h"
#include "dixstruct.h"
#include "gcstruct.h"
#include "servermd.h"
#include "picturestr.h"

static char **filterNames;

static int nfilterNames;

/*
 * standard but not required filters don't have constant indices
 */

int
PictureGetFilterId(char *filter, int len, Bool makeit)
{
    int i;

    char *name;

    char **names;

    if (len < 0)
        len = strlen(filter);
    for (i = 0; i < nfilterNames; i++)
        if (!CompareISOLatin1Lowered
            ((unsigned char *) filterNames[i], -1, (unsigned char *) filter,
             len))
            return i;
    if (!makeit)
        return -1;
    name = malloc(len + 1);
    if (!name)
        return -1;
    memcpy(name, filter, len);
    name[len] = '\0';
    if (filterNames)
        names = realloc(filterNames, (nfilterNames + 1) * sizeof(char *));
    else
        names = malloc(sizeof(char *));
    if (!names) {
        free(name);
        return -1;
    }
    filterNames = names;
    i = nfilterNames++;
    filterNames[i] = name;
    return i;
}

static Bool
PictureSetDefaultIds(void)
{
    /* careful here -- this list must match the #define values */

    if (PictureGetFilterId(FilterNearest, -1, TRUE) != PictFilterNearest)
        return FALSE;
    if (PictureGetFilterId(FilterBilinear, -1, TRUE) != PictFilterBilinear)
        return FALSE;

    if (PictureGetFilterId(FilterFast, -1, TRUE) != PictFilterFast)
        return FALSE;
    if (PictureGetFilterId(FilterGood, -1, TRUE) != PictFilterGood)
        return FALSE;
    if (PictureGetFilterId(FilterBest, -1, TRUE) != PictFilterBest)
        return FALSE;

    if (PictureGetFilterId(FilterConvolution, -1, TRUE) !=
        PictFilterConvolution)
        return FALSE;
    return TRUE;
}

char *
PictureGetFilterName(int id)
{
    if (0 <= id && id < nfilterNames)
        return filterNames[id];
    else
        return 0;
}

static void
PictureFreeFilterIds(void)
{
    int i;

    for (i = 0; i < nfilterNames; i++)
        free(filterNames[i]);
    free(filterNames);
    nfilterNames = 0;
    filterNames = 0;
}

_X_EXPORT int
PictureAddFilter(ScreenPtr pScreen,
                 char *filter, PictFilterValidateParamsProcPtr ValidateParams)
{
    PictureScreenPtr ps = GetPictureScreen(pScreen);

    int id = PictureGetFilterId(filter, -1, TRUE);

    int i;

    PictFilterPtr filters;

    if (id < 0)
        return -1;
    /*
     * It's an error to attempt to reregister a filter
     */
    for (i = 0; i < ps->nfilters; i++)
        if (ps->filters[i].id == id)
            return -1;
    if (ps->filters)
        filters =
            realloc(ps->filters, (ps->nfilters + 1) * sizeof(PictFilterRec));
    else
        filters = malloc(sizeof(PictFilterRec));
    if (!filters)
        return -1;
    ps->filters = filters;
    i = ps->nfilters++;
    ps->filters[i].name = PictureGetFilterName(id);
    ps->filters[i].id = id;
    ps->filters[i].ValidateParams = ValidateParams;
    return id;
}

_X_EXPORT Bool
PictureSetFilterAlias(ScreenPtr pScreen, char *filter, char *alias)
{
    PictureScreenPtr ps = GetPictureScreen(pScreen);

    int filter_id = PictureGetFilterId(filter, -1, FALSE);

    int alias_id = PictureGetFilterId(alias, -1, TRUE);

    int i;

    if (filter_id < 0 || alias_id < 0)
        return FALSE;
    for (i = 0; i < ps->nfilterAliases; i++)
        if (ps->filterAliases[i].alias_id == alias_id)
            break;
    if (i == ps->nfilterAliases) {
        PictFilterAliasPtr aliases;

        if (ps->filterAliases)
            aliases = realloc(ps->filterAliases,
                               (ps->nfilterAliases + 1) *
                               sizeof(PictFilterAliasRec));
        else
            aliases = malloc(sizeof(PictFilterAliasRec));
        if (!aliases)
            return FALSE;
        ps->filterAliases = aliases;
        ps->filterAliases[i].alias = PictureGetFilterName(alias_id);
        ps->filterAliases[i].alias_id = alias_id;
        ps->nfilterAliases++;
    }
    ps->filterAliases[i].filter_id = filter_id;
    return TRUE;
}

PictFilterPtr
PictureFindFilter(ScreenPtr pScreen, char *name, int len)
{
    PictureScreenPtr ps = GetPictureScreen(pScreen);

    int id = PictureGetFilterId(name, len, FALSE);

    int i;

    if (id < 0)
        return 0;
    /* Check for an alias, allow them to recurse */
    for (i = 0; i < ps->nfilterAliases; i++)
        if (ps->filterAliases[i].alias_id == id) {
            id = ps->filterAliases[i].filter_id;
            i = 0;
        }
    /* find the filter */
    for (i = 0; i < ps->nfilters; i++)
        if (ps->filters[i].id == id)
            return &ps->filters[i];
    return 0;
}

static Bool
convolutionFilterValidateParams(PicturePtr pPicture,
                                int filter, xFixed * params, int nparams)
{
    if (nparams < 3)
        return FALSE;

    if (xFixedFrac(params[0]) || xFixedFrac(params[1]))
        return FALSE;

    nparams -= 2;
    if ((xFixedToInt(params[0]) * xFixedToInt(params[1])) > nparams)
        return FALSE;

    return TRUE;
}

Bool
PictureSetDefaultFilters(ScreenPtr pScreen)
{
    if (!filterNames)
        if (!PictureSetDefaultIds())
            return FALSE;
    if (PictureAddFilter(pScreen, FilterNearest, 0) < 0)
        return FALSE;
    if (PictureAddFilter(pScreen, FilterBilinear, 0) < 0)
        return FALSE;

    if (!PictureSetFilterAlias(pScreen, FilterNearest, FilterFast))
        return FALSE;
    if (!PictureSetFilterAlias(pScreen, FilterBilinear, FilterGood))
        return FALSE;
    if (!PictureSetFilterAlias(pScreen, FilterBilinear, FilterBest))
        return FALSE;

    if (PictureAddFilter
        (pScreen, FilterConvolution, convolutionFilterValidateParams) < 0)
        return FALSE;

    return TRUE;
}

void
PictureResetFilters(ScreenPtr pScreen)
{
    PictureScreenPtr ps = GetPictureScreen(pScreen);

    free(ps->filters);
    free(ps->filterAliases);
    PictureFreeFilterIds();
}

int
SetPictureFilter(PicturePtr pPicture, char *name, int len, xFixed * params,
                 int nparams)
{
    PictFilterPtr pFilter;

    xFixed *new_params;

    int i, s, result;

    pFilter = PictureFindFilter(screenInfo.screens[0], name, len);
    if (!pFilter)
        return BadName;

    if (pPicture->pDrawable == NULL) {
        /* For source pictures, the picture isn't tied to a screen.  So, ensure
         * that all screens can handle a filter we set for the picture.
         */
        for (s = 0; s < screenInfo.numScreens; s++) {
            PictFilterPtr tmp = PictureFindFilter(screenInfo.screens[s], name, len);
            if (!tmp) return BadName;
            if (tmp->id != pFilter->id) {
                return BadMatch;
            }
        }
    }

    if (pFilter->ValidateParams) {
        if (!(*pFilter->ValidateParams)
            (pPicture, pFilter->id, params, nparams))
            return BadMatch;
    }
    else if (nparams)
        return BadMatch;

    if (nparams != pPicture->filter_nparams) {
        new_params = malloc(nparams * sizeof(xFixed));
        if (!new_params)
            return BadAlloc;
        free(pPicture->filter_params);
        pPicture->filter_params = new_params;
        pPicture->filter_nparams = nparams;
    }
    for (i = 0; i < nparams; i++)
        pPicture->filter_params[i] = params[i];
    pPicture->filter = pFilter->id;

    if (pPicture->pDrawable) {
        ScreenPtr pScreen = pPicture->pDrawable->pScreen;

        PictureScreenPtr ps = GetPictureScreen(pScreen);

        result = (*ps->ChangePictureFilter) (pPicture, pPicture->filter,
                                             params, nparams);
        return result;
    }
    return Success;
}