/*
 * Copyright © 2001 Keith Packard
 *
 * Partly based on code that is Copyright © The XFree86 Project Inc.
 *
 * 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.
 *
 * Authors:
 *    Eric Anholt <eric@anholt.net>
 *    Michel Dänzer <michel@tungstengraphics.com>
 *
 */

#ifdef HAVE_DIX_CONFIG_H
#include <dix-config.h>
#endif
#include "exa_priv.h"
#include <X11/fonts/fontstruct.h>
#include "dixfontstr.h"
#include "exa.h"

static void
exaFillSpans(DrawablePtr pDrawable, GCPtr pGC, int n,
             DDXPointPtr ppt, int *pwidth, int fSorted)
{
    ScreenPtr pScreen = pDrawable->pScreen;

    ExaScreenPriv(pScreen);
    RegionPtr pClip = fbGetCompositeClip(pGC);
    PixmapPtr pPixmap = exaGetDrawablePixmap(pDrawable);

    ExaPixmapPriv(pPixmap);
    BoxPtr pextent, pbox;
    int nbox;
    int extentX1, extentX2, extentY1, extentY2;
    int fullX1, fullX2, fullY1;
    int partX1, partX2;
    int off_x, off_y;

    if (pExaScr->fallback_counter ||
        pExaScr->swappedOut ||
        pGC->fillStyle != FillSolid || pExaPixmap->accel_blocked) {
        ExaCheckFillSpans(pDrawable, pGC, n, ppt, pwidth, fSorted);
        return;
    }

    if (pExaScr->do_migration) {
        ExaMigrationRec pixmaps[1];

        pixmaps[0].as_dst = TRUE;
        pixmaps[0].as_src = FALSE;
        pixmaps[0].pPix = pPixmap;
        pixmaps[0].pReg = NULL;

        exaDoMigration(pixmaps, 1, TRUE);
    }

    if (!(pPixmap = exaGetOffscreenPixmap(pDrawable, &off_x, &off_y)) ||
        !(*pExaScr->info->PrepareSolid) (pPixmap,
                                         pGC->alu,
                                         pGC->planemask, pGC->fgPixel)) {
        ExaCheckFillSpans(pDrawable, pGC, n, ppt, pwidth, fSorted);
        return;
    }

    pextent = RegionExtents(pClip);
    extentX1 = pextent->x1;
    extentY1 = pextent->y1;
    extentX2 = pextent->x2;
    extentY2 = pextent->y2;
    while (n--) {
        fullX1 = ppt->x;
        fullY1 = ppt->y;
        fullX2 = fullX1 + (int) *pwidth;
        ppt++;
        pwidth++;

        if (fullY1 < extentY1 || extentY2 <= fullY1)
            continue;

        if (fullX1 < extentX1)
            fullX1 = extentX1;

        if (fullX2 > extentX2)
            fullX2 = extentX2;

        if (fullX1 >= fullX2)
            continue;

        nbox = RegionNumRects(pClip);
        if (nbox == 1) {
            (*pExaScr->info->Solid) (pPixmap,
                                     fullX1 + off_x, fullY1 + off_y,
                                     fullX2 + off_x, fullY1 + 1 + off_y);
        }
        else {
            pbox = RegionRects(pClip);
            while (nbox--) {
                if (pbox->y1 <= fullY1 && fullY1 < pbox->y2) {
                    partX1 = pbox->x1;
                    if (partX1 < fullX1)
                        partX1 = fullX1;
                    partX2 = pbox->x2;
                    if (partX2 > fullX2)
                        partX2 = fullX2;
                    if (partX2 > partX1) {
                        (*pExaScr->info->Solid) (pPixmap,
                                                 partX1 + off_x, fullY1 + off_y,
                                                 partX2 + off_x,
                                                 fullY1 + 1 + off_y);
                    }
                }
                pbox++;
            }
        }
    }
    (*pExaScr->info->DoneSolid) (pPixmap);
    exaMarkSync(pScreen);
}

static Bool
exaDoPutImage(DrawablePtr pDrawable, GCPtr pGC, int depth, int x, int y,
              int w, int h, int format, char *bits, int src_stride)
{
    ExaScreenPriv(pDrawable->pScreen);
    PixmapPtr pPix = exaGetDrawablePixmap(pDrawable);

    ExaPixmapPriv(pPix);
    RegionPtr pClip;
    BoxPtr pbox;
    int nbox;
    int xoff, yoff;
    int bpp = pDrawable->bitsPerPixel;
    Bool ret = TRUE;

    if (pExaScr->fallback_counter || pExaPixmap->accel_blocked ||
        !pExaScr->info->UploadToScreen)
        return FALSE;

    /* If there's a system copy, we want to save the result there */
    if (pExaPixmap->pDamage)
        return FALSE;

    /* Don't bother with under 8bpp, XYPixmaps. */
    if (format != ZPixmap || bpp < 8)
        return FALSE;

    /* Only accelerate copies: no rop or planemask. */
    if (!EXA_PM_IS_SOLID(pDrawable, pGC->planemask) || pGC->alu != GXcopy)
        return FALSE;

    if (pExaScr->swappedOut)
        return FALSE;

    if (pExaScr->do_migration) {
        ExaMigrationRec pixmaps[1];

        pixmaps[0].as_dst = TRUE;
        pixmaps[0].as_src = FALSE;
        pixmaps[0].pPix = pPix;
        pixmaps[0].pReg = DamagePendingRegion(pExaPixmap->pDamage);

        exaDoMigration(pixmaps, 1, TRUE);
    }

    pPix = exaGetOffscreenPixmap(pDrawable, &xoff, &yoff);

    if (!pPix)
        return FALSE;

    x += pDrawable->x;
    y += pDrawable->y;

    pClip = fbGetCompositeClip(pGC);
    for (nbox = RegionNumRects(pClip),
         pbox = RegionRects(pClip); nbox--; pbox++) {
        int x1 = x;
        int y1 = y;
        int x2 = x + w;
        int y2 = y + h;
        char *src;
        Bool ok;

        if (x1 < pbox->x1)
            x1 = pbox->x1;
        if (y1 < pbox->y1)
            y1 = pbox->y1;
        if (x2 > pbox->x2)
            x2 = pbox->x2;
        if (y2 > pbox->y2)
            y2 = pbox->y2;
        if (x1 >= x2 || y1 >= y2)
            continue;

        src = bits + (y1 - y) * src_stride + (x1 - x) * (bpp / 8);
        ok = pExaScr->info->UploadToScreen(pPix, x1 + xoff, y1 + yoff,
                                           x2 - x1, y2 - y1, src, src_stride);
        /* We have to fall back completely, and ignore what has already been completed.
         * Messing with the fb layer directly like we used to is completely unacceptable.
         */
        if (!ok) {
            ret = FALSE;
            break;
        }
    }

    if (ret)
        exaMarkSync(pDrawable->pScreen);

    return ret;
}

static void
exaPutImage(DrawablePtr pDrawable, GCPtr pGC, int depth, int x, int y,
            int w, int h, int leftPad, int format, char *bits)
{
    if (!exaDoPutImage(pDrawable, pGC, depth, x, y, w, h, format, bits,
                       PixmapBytePad(w, pDrawable->depth)))
        ExaCheckPutImage(pDrawable, pGC, depth, x, y, w, h, leftPad, format,
                         bits);
}

static Bool inline
exaCopyNtoNTwoDir(DrawablePtr pSrcDrawable, DrawablePtr pDstDrawable,
                  GCPtr pGC, BoxPtr pbox, int nbox, int dx, int dy)
{
    ExaScreenPriv(pDstDrawable->pScreen);
    PixmapPtr pSrcPixmap, pDstPixmap;
    int src_off_x, src_off_y, dst_off_x, dst_off_y;
    int dirsetup;

    /* Need to get both pixmaps to call the driver routines */
    pSrcPixmap = exaGetOffscreenPixmap(pSrcDrawable, &src_off_x, &src_off_y);
    pDstPixmap = exaGetOffscreenPixmap(pDstDrawable, &dst_off_x, &dst_off_y);
    if (!pSrcPixmap || !pDstPixmap)
        return FALSE;

    /*
     * Now the case of a chip that only supports xdir = ydir = 1 or
     * xdir = ydir = -1, but we have xdir != ydir.
     */
    dirsetup = 0;               /* No direction set up yet. */
    for (; nbox; pbox++, nbox--) {
        if (dx >= 0 && (src_off_y + pbox->y1 + dy) != pbox->y1) {
            /* Do a xdir = ydir = -1 blit instead. */
            if (dirsetup != -1) {
                if (dirsetup != 0)
                    pExaScr->info->DoneCopy(pDstPixmap);
                dirsetup = -1;
                if (!(*pExaScr->info->PrepareCopy) (pSrcPixmap,
                                                    pDstPixmap,
                                                    -1, -1,
                                                    pGC ? pGC->alu : GXcopy,
                                                    pGC ? pGC->planemask :
                                                    FB_ALLONES))
                    return FALSE;
            }
            (*pExaScr->info->Copy) (pDstPixmap,
                                    src_off_x + pbox->x1 + dx,
                                    src_off_y + pbox->y1 + dy,
                                    dst_off_x + pbox->x1,
                                    dst_off_y + pbox->y1,
                                    pbox->x2 - pbox->x1, pbox->y2 - pbox->y1);
        }
        else if (dx < 0 && (src_off_y + pbox->y1 + dy) != pbox->y1) {
            /* Do a xdir = ydir = 1 blit instead. */
            if (dirsetup != 1) {
                if (dirsetup != 0)
                    pExaScr->info->DoneCopy(pDstPixmap);
                dirsetup = 1;
                if (!(*pExaScr->info->PrepareCopy) (pSrcPixmap,
                                                    pDstPixmap,
                                                    1, 1,
                                                    pGC ? pGC->alu : GXcopy,
                                                    pGC ? pGC->planemask :
                                                    FB_ALLONES))
                    return FALSE;
            }
            (*pExaScr->info->Copy) (pDstPixmap,
                                    src_off_x + pbox->x1 + dx,
                                    src_off_y + pbox->y1 + dy,
                                    dst_off_x + pbox->x1,
                                    dst_off_y + pbox->y1,
                                    pbox->x2 - pbox->x1, pbox->y2 - pbox->y1);
        }
        else if (dx >= 0) {
            /*
             * xdir = 1, ydir = -1.
             * Perform line-by-line xdir = ydir = 1 blits, going up.
             */
            int i;

            if (dirsetup != 1) {
                if (dirsetup != 0)
                    pExaScr->info->DoneCopy(pDstPixmap);
                dirsetup = 1;
                if (!(*pExaScr->info->PrepareCopy) (pSrcPixmap,
                                                    pDstPixmap,
                                                    1, 1,
                                                    pGC ? pGC->alu : GXcopy,
                                                    pGC ? pGC->planemask :
                                                    FB_ALLONES))
                    return FALSE;
            }
            for (i = pbox->y2 - pbox->y1 - 1; i >= 0; i--)
                (*pExaScr->info->Copy) (pDstPixmap,
                                        src_off_x + pbox->x1 + dx,
                                        src_off_y + pbox->y1 + dy + i,
                                        dst_off_x + pbox->x1,
                                        dst_off_y + pbox->y1 + i,
                                        pbox->x2 - pbox->x1, 1);
        }
        else {
            /*
             * xdir = -1, ydir = 1.
             * Perform line-by-line xdir = ydir = -1 blits, going down.
             */
            int i;

            if (dirsetup != -1) {
                if (dirsetup != 0)
                    pExaScr->info->DoneCopy(pDstPixmap);
                dirsetup = -1;
                if (!(*pExaScr->info->PrepareCopy) (pSrcPixmap,
                                                    pDstPixmap,
                                                    -1, -1,
                                                    pGC ? pGC->alu : GXcopy,
                                                    pGC ? pGC->planemask :
                                                    FB_ALLONES))
                    return FALSE;
            }
            for (i = 0; i < pbox->y2 - pbox->y1; i++)
                (*pExaScr->info->Copy) (pDstPixmap,
                                        src_off_x + pbox->x1 + dx,
                                        src_off_y + pbox->y1 + dy + i,
                                        dst_off_x + pbox->x1,
                                        dst_off_y + pbox->y1 + i,
                                        pbox->x2 - pbox->x1, 1);
        }
    }
    if (dirsetup != 0)
        pExaScr->info->DoneCopy(pDstPixmap);
    exaMarkSync(pDstDrawable->pScreen);
    return TRUE;
}

Bool
exaHWCopyNtoN(DrawablePtr pSrcDrawable,
              DrawablePtr pDstDrawable,
              GCPtr pGC,
              BoxPtr pbox,
              int nbox, int dx, int dy, Bool reverse, Bool upsidedown)
{
    ExaScreenPriv(pDstDrawable->pScreen);
    PixmapPtr pSrcPixmap, pDstPixmap;
    ExaPixmapPrivPtr pSrcExaPixmap, pDstExaPixmap;
    int src_off_x, src_off_y;
    int dst_off_x, dst_off_y;
    RegionPtr srcregion = NULL, dstregion = NULL;
    xRectangle *rects;
    Bool ret = TRUE;

    /* avoid doing copy operations if no boxes */
    if (nbox == 0)
        return TRUE;

    pSrcPixmap = exaGetDrawablePixmap(pSrcDrawable);
    pDstPixmap = exaGetDrawablePixmap(pDstDrawable);

    exaGetDrawableDeltas(pSrcDrawable, pSrcPixmap, &src_off_x, &src_off_y);
    exaGetDrawableDeltas(pDstDrawable, pDstPixmap, &dst_off_x, &dst_off_y);

    rects = xallocarray(nbox, sizeof(xRectangle));

    if (rects) {
        int i;
        int ordering;

        for (i = 0; i < nbox; i++) {
            rects[i].x = pbox[i].x1 + dx + src_off_x;
            rects[i].y = pbox[i].y1 + dy + src_off_y;
            rects[i].width = pbox[i].x2 - pbox[i].x1;
            rects[i].height = pbox[i].y2 - pbox[i].y1;
        }

        /* This must match the RegionCopy() logic for reversing rect order */
        if (nbox == 1 || (dx > 0 && dy > 0) ||
            (pDstDrawable != pSrcDrawable &&
             (pDstDrawable->type != DRAWABLE_WINDOW ||
              pSrcDrawable->type != DRAWABLE_WINDOW)))
            ordering = CT_YXBANDED;
        else
            ordering = CT_UNSORTED;

        srcregion = RegionFromRects(nbox, rects, ordering);
        free(rects);

        if (!pGC || !exaGCReadsDestination(pDstDrawable, pGC->planemask,
                                           pGC->fillStyle, pGC->alu,
                                           pGC->clientClip != NULL)) {
            dstregion = RegionCreate(NullBox, 0);
            RegionCopy(dstregion, srcregion);
            RegionTranslate(dstregion, dst_off_x - dx - src_off_x,
                            dst_off_y - dy - src_off_y);
        }
    }

    pSrcExaPixmap = ExaGetPixmapPriv(pSrcPixmap);
    pDstExaPixmap = ExaGetPixmapPriv(pDstPixmap);

    /* Check whether the accelerator can use this pixmap.
     * If the pitch of the pixmaps is out of range, there's nothing
     * we can do but fall back to software rendering.
     */
    if (pSrcExaPixmap->accel_blocked & EXA_RANGE_PITCH ||
        pDstExaPixmap->accel_blocked & EXA_RANGE_PITCH)
        goto fallback;

    /* If the width or the height of either of the pixmaps
     * is out of range, check whether the boxes are actually out of the
     * addressable range as well. If they aren't, we can still do
     * the copying in hardware.
     */
    if (pSrcExaPixmap->accel_blocked || pDstExaPixmap->accel_blocked) {
        int i;

        for (i = 0; i < nbox; i++) {
            /* src */
            if ((pbox[i].x2 + dx + src_off_x) >= pExaScr->info->maxX ||
                (pbox[i].y2 + dy + src_off_y) >= pExaScr->info->maxY)
                goto fallback;

            /* dst */
            if ((pbox[i].x2 + dst_off_x) >= pExaScr->info->maxX ||
                (pbox[i].y2 + dst_off_y) >= pExaScr->info->maxY)
                goto fallback;
        }
    }

    if (pExaScr->do_migration) {
        ExaMigrationRec pixmaps[2];

        pixmaps[0].as_dst = TRUE;
        pixmaps[0].as_src = FALSE;
        pixmaps[0].pPix = pDstPixmap;
        pixmaps[0].pReg = dstregion;
        pixmaps[1].as_dst = FALSE;
        pixmaps[1].as_src = TRUE;
        pixmaps[1].pPix = pSrcPixmap;
        pixmaps[1].pReg = srcregion;

        exaDoMigration(pixmaps, 2, TRUE);
    }

    /* Mixed directions must be handled specially if the card is lame */
    if ((pExaScr->info->flags & EXA_TWO_BITBLT_DIRECTIONS) &&
        reverse != upsidedown) {
        if (exaCopyNtoNTwoDir(pSrcDrawable, pDstDrawable, pGC, pbox, nbox,
                              dx, dy))
            goto out;
        goto fallback;
    }

    if (exaPixmapHasGpuCopy(pDstPixmap)) {
        /* Normal blitting. */
        if (exaPixmapHasGpuCopy(pSrcPixmap)) {
            if (!(*pExaScr->info->PrepareCopy)
                (pSrcPixmap, pDstPixmap, reverse ? -1 : 1, upsidedown ? -1 : 1,
                 pGC ? pGC->alu : GXcopy, pGC ? pGC->planemask : FB_ALLONES)) {
                goto fallback;
            }

            while (nbox--) {
                (*pExaScr->info->Copy) (pDstPixmap,
                                        pbox->x1 + dx + src_off_x,
                                        pbox->y1 + dy + src_off_y,
                                        pbox->x1 + dst_off_x,
                                        pbox->y1 + dst_off_y,
                                        pbox->x2 - pbox->x1,
                                        pbox->y2 - pbox->y1);
                pbox++;
            }

            (*pExaScr->info->DoneCopy) (pDstPixmap);
            exaMarkSync(pDstDrawable->pScreen);
            /* UTS: mainly for SHM PutImage's secondary path.
             *
             * Only taking this path for directly accessible pixmaps.
             */
        }
        else if (!pDstExaPixmap->pDamage && pSrcExaPixmap->sys_ptr) {
            int bpp = pSrcDrawable->bitsPerPixel;
            int src_stride = exaGetPixmapPitch(pSrcPixmap);
            CARD8 *src = NULL;

            if (!pExaScr->info->UploadToScreen)
                goto fallback;

            if (pSrcDrawable->bitsPerPixel != pDstDrawable->bitsPerPixel)
                goto fallback;

            if (pSrcDrawable->bitsPerPixel < 8)
                goto fallback;

            if (pGC &&
                !(pGC->alu == GXcopy &&
                  EXA_PM_IS_SOLID(pSrcDrawable, pGC->planemask)))
                goto fallback;

            while (nbox--) {
                src =
                    pSrcExaPixmap->sys_ptr + (pbox->y1 + dy +
                                              src_off_y) * src_stride +
                    (pbox->x1 + dx + src_off_x) * (bpp / 8);
                if (!pExaScr->info->
                    UploadToScreen(pDstPixmap, pbox->x1 + dst_off_x,
                                   pbox->y1 + dst_off_y, pbox->x2 - pbox->x1,
                                   pbox->y2 - pbox->y1, (char *) src,
                                   src_stride))
                    goto fallback;

                pbox++;
            }
        }
        else
            goto fallback;
    }
    else
        goto fallback;

    goto out;

 fallback:
    ret = FALSE;

 out:
    if (dstregion) {
        RegionUninit(dstregion);
        RegionDestroy(dstregion);
    }
    if (srcregion) {
        RegionUninit(srcregion);
        RegionDestroy(srcregion);
    }

    return ret;
}

void
exaCopyNtoN(DrawablePtr pSrcDrawable,
            DrawablePtr pDstDrawable,
            GCPtr pGC,
            BoxPtr pbox,
            int nbox,
            int dx,
            int dy,
            Bool reverse, Bool upsidedown, Pixel bitplane, void *closure)
{
    ExaScreenPriv(pDstDrawable->pScreen);

    if (pExaScr->fallback_counter ||
        (pExaScr->fallback_flags & EXA_FALLBACK_COPYWINDOW))
        return;

    if (exaHWCopyNtoN
        (pSrcDrawable, pDstDrawable, pGC, pbox, nbox, dx, dy, reverse,
         upsidedown))
        return;

    /* This is a CopyWindow, it's cleaner to fallback at the original call. */
    if (pExaScr->fallback_flags & EXA_ACCEL_COPYWINDOW) {
        pExaScr->fallback_flags |= EXA_FALLBACK_COPYWINDOW;
        return;
    }

    /* fallback */
    ExaCheckCopyNtoN(pSrcDrawable, pDstDrawable, pGC, pbox, nbox, dx, dy,
                     reverse, upsidedown, bitplane, closure);
}

RegionPtr
exaCopyArea(DrawablePtr pSrcDrawable, DrawablePtr pDstDrawable, GCPtr pGC,
            int srcx, int srcy, int width, int height, int dstx, int dsty)
{
    ExaScreenPriv(pDstDrawable->pScreen);

    if (pExaScr->fallback_counter || pExaScr->swappedOut) {
        return ExaCheckCopyArea(pSrcDrawable, pDstDrawable, pGC,
                                srcx, srcy, width, height, dstx, dsty);
    }

    return miDoCopy(pSrcDrawable, pDstDrawable, pGC,
                    srcx, srcy, width, height,
                    dstx, dsty, exaCopyNtoN, 0, NULL);
}

static void
exaPolyPoint(DrawablePtr pDrawable, GCPtr pGC, int mode, int npt,
             DDXPointPtr ppt)
{
    ExaScreenPriv(pDrawable->pScreen);
    int i;
    xRectangle *prect;

    /* If we can't reuse the current GC as is, don't bother accelerating the
     * points.
     */
    if (pExaScr->fallback_counter || pGC->fillStyle != FillSolid) {
        ExaCheckPolyPoint(pDrawable, pGC, mode, npt, ppt);
        return;
    }

    prect = xallocarray(npt, sizeof(xRectangle));
    for (i = 0; i < npt; i++) {
        prect[i].x = ppt[i].x;
        prect[i].y = ppt[i].y;
        if (i > 0 && mode == CoordModePrevious) {
            prect[i].x += prect[i - 1].x;
            prect[i].y += prect[i - 1].y;
        }
        prect[i].width = 1;
        prect[i].height = 1;
    }
    pGC->ops->PolyFillRect(pDrawable, pGC, npt, prect);
    free(prect);
}

/**
 * exaPolylines() checks if it can accelerate the lines as a group of
 * horizontal or vertical lines (rectangles), and uses existing rectangle fill
 * acceleration if so.
 */
static void
exaPolylines(DrawablePtr pDrawable, GCPtr pGC, int mode, int npt,
             DDXPointPtr ppt)
{
    ExaScreenPriv(pDrawable->pScreen);
    xRectangle *prect;
    int x1, x2, y1, y2;
    int i;

    if (pExaScr->fallback_counter) {
        ExaCheckPolylines(pDrawable, pGC, mode, npt, ppt);
        return;
    }

    /* Don't try to do wide lines or non-solid fill style. */
    if (pGC->lineWidth != 0 || pGC->lineStyle != LineSolid ||
        pGC->fillStyle != FillSolid) {
        ExaCheckPolylines(pDrawable, pGC, mode, npt, ppt);
        return;
    }

    prect = xallocarray(npt - 1, sizeof(xRectangle));
    x1 = ppt[0].x;
    y1 = ppt[0].y;
    /* If we have any non-horizontal/vertical, fall back. */
    for (i = 0; i < npt - 1; i++) {
        if (mode == CoordModePrevious) {
            x2 = x1 + ppt[i + 1].x;
            y2 = y1 + ppt[i + 1].y;
        }
        else {
            x2 = ppt[i + 1].x;
            y2 = ppt[i + 1].y;
        }

        if (x1 != x2 && y1 != y2) {
            free(prect);
            ExaCheckPolylines(pDrawable, pGC, mode, npt, ppt);
            return;
        }

        if (x1 < x2) {
            prect[i].x = x1;
            prect[i].width = x2 - x1 + 1;
        }
        else {
            prect[i].x = x2;
            prect[i].width = x1 - x2 + 1;
        }
        if (y1 < y2) {
            prect[i].y = y1;
            prect[i].height = y2 - y1 + 1;
        }
        else {
            prect[i].y = y2;
            prect[i].height = y1 - y2 + 1;
        }

        x1 = x2;
        y1 = y2;
    }
    pGC->ops->PolyFillRect(pDrawable, pGC, npt - 1, prect);
    free(prect);
}

/**
 * exaPolySegment() checks if it can accelerate the lines as a group of
 * horizontal or vertical lines (rectangles), and uses existing rectangle fill
 * acceleration if so.
 */
static void
exaPolySegment(DrawablePtr pDrawable, GCPtr pGC, int nseg, xSegment * pSeg)
{
    ExaScreenPriv(pDrawable->pScreen);
    xRectangle *prect;
    int i;

    /* Don't try to do wide lines or non-solid fill style. */
    if (pExaScr->fallback_counter || pGC->lineWidth != 0 ||
        pGC->lineStyle != LineSolid || pGC->fillStyle != FillSolid) {
        ExaCheckPolySegment(pDrawable, pGC, nseg, pSeg);
        return;
    }

    /* If we have any non-horizontal/vertical, fall back. */
    for (i = 0; i < nseg; i++) {
        if (pSeg[i].x1 != pSeg[i].x2 && pSeg[i].y1 != pSeg[i].y2) {
            ExaCheckPolySegment(pDrawable, pGC, nseg, pSeg);
            return;
        }
    }

    prect = xallocarray(nseg, sizeof(xRectangle));
    for (i = 0; i < nseg; i++) {
        if (pSeg[i].x1 < pSeg[i].x2) {
            prect[i].x = pSeg[i].x1;
            prect[i].width = pSeg[i].x2 - pSeg[i].x1 + 1;
        }
        else {
            prect[i].x = pSeg[i].x2;
            prect[i].width = pSeg[i].x1 - pSeg[i].x2 + 1;
        }
        if (pSeg[i].y1 < pSeg[i].y2) {
            prect[i].y = pSeg[i].y1;
            prect[i].height = pSeg[i].y2 - pSeg[i].y1 + 1;
        }
        else {
            prect[i].y = pSeg[i].y2;
            prect[i].height = pSeg[i].y1 - pSeg[i].y2 + 1;
        }

        /* don't paint last pixel */
        if (pGC->capStyle == CapNotLast) {
            if (prect[i].width == 1)
                prect[i].height--;
            else
                prect[i].width--;
        }
    }
    pGC->ops->PolyFillRect(pDrawable, pGC, nseg, prect);
    free(prect);
}

static Bool exaFillRegionSolid(DrawablePtr pDrawable, RegionPtr pRegion,
                               Pixel pixel, CARD32 planemask, CARD32 alu,
                               Bool hasClientClip);

static void
exaPolyFillRect(DrawablePtr pDrawable, GCPtr pGC, int nrect, xRectangle *prect)
{
    ExaScreenPriv(pDrawable->pScreen);
    RegionPtr pClip = fbGetCompositeClip(pGC);
    PixmapPtr pPixmap = exaGetDrawablePixmap(pDrawable);

    ExaPixmapPriv(pPixmap);
    register BoxPtr pbox;
    BoxPtr pextent;
    int extentX1, extentX2, extentY1, extentY2;
    int fullX1, fullX2, fullY1, fullY2;
    int partX1, partX2, partY1, partY2;
    int xoff, yoff;
    int xorg, yorg;
    int n;
    RegionPtr pReg = RegionFromRects(nrect, prect, CT_UNSORTED);

    /* Compute intersection of rects and clip region */
    RegionTranslate(pReg, pDrawable->x, pDrawable->y);
    RegionIntersect(pReg, pClip, pReg);

    if (!RegionNumRects(pReg)) {
        goto out;
    }

    exaGetDrawableDeltas(pDrawable, pPixmap, &xoff, &yoff);

    if (pExaScr->fallback_counter || pExaScr->swappedOut ||
        pExaPixmap->accel_blocked) {
        goto fallback;
    }

    /* For ROPs where overlaps don't matter, convert rectangles to region and
     * call exaFillRegion{Solid,Tiled}.
     */
    if ((pGC->fillStyle == FillSolid || pGC->fillStyle == FillTiled) &&
        (nrect == 1 || pGC->alu == GXcopy || pGC->alu == GXclear ||
         pGC->alu == GXnoop || pGC->alu == GXcopyInverted ||
         pGC->alu == GXset)) {
        if (((pGC->fillStyle == FillSolid || pGC->tileIsPixel) &&
             exaFillRegionSolid(pDrawable, pReg, pGC->fillStyle == FillSolid ?
                                pGC->fgPixel : pGC->tile.pixel, pGC->planemask,
                                pGC->alu, pGC->clientClip != NULL)) ||
            (pGC->fillStyle == FillTiled && !pGC->tileIsPixel &&
             exaFillRegionTiled(pDrawable, pReg, pGC->tile.pixmap, &pGC->patOrg,
                                pGC->planemask, pGC->alu,
                                pGC->clientClip != NULL))) {
            goto out;
        }
    }

    if (pGC->fillStyle != FillSolid &&
        !(pGC->tileIsPixel && pGC->fillStyle == FillTiled)) {
        goto fallback;
    }

    if (pExaScr->do_migration) {
        ExaMigrationRec pixmaps[1];

        pixmaps[0].as_dst = TRUE;
        pixmaps[0].as_src = FALSE;
        pixmaps[0].pPix = pPixmap;
        pixmaps[0].pReg = NULL;

        exaDoMigration(pixmaps, 1, TRUE);
    }

    if (!exaPixmapHasGpuCopy(pPixmap) ||
        !(*pExaScr->info->PrepareSolid) (pPixmap,
                                         pGC->alu,
                                         pGC->planemask, pGC->fgPixel)) {
 fallback:
        ExaCheckPolyFillRect(pDrawable, pGC, nrect, prect);
        goto out;
    }

    xorg = pDrawable->x;
    yorg = pDrawable->y;

    pextent = RegionExtents(pClip);
    extentX1 = pextent->x1;
    extentY1 = pextent->y1;
    extentX2 = pextent->x2;
    extentY2 = pextent->y2;
    while (nrect--) {
        fullX1 = prect->x + xorg;
        fullY1 = prect->y + yorg;
        fullX2 = fullX1 + (int) prect->width;
        fullY2 = fullY1 + (int) prect->height;
        prect++;

        if (fullX1 < extentX1)
            fullX1 = extentX1;

        if (fullY1 < extentY1)
            fullY1 = extentY1;

        if (fullX2 > extentX2)
            fullX2 = extentX2;

        if (fullY2 > extentY2)
            fullY2 = extentY2;

        if ((fullX1 >= fullX2) || (fullY1 >= fullY2))
            continue;
        n = RegionNumRects(pClip);
        if (n == 1) {
            (*pExaScr->info->Solid) (pPixmap,
                                     fullX1 + xoff, fullY1 + yoff,
                                     fullX2 + xoff, fullY2 + yoff);
        }
        else {
            pbox = RegionRects(pClip);
            /*
             * clip the rectangle to each box in the clip region
             * this is logically equivalent to calling Intersect(),
             * but rectangles may overlap each other here.
             */
            while (n--) {
                partX1 = pbox->x1;
                if (partX1 < fullX1)
                    partX1 = fullX1;
                partY1 = pbox->y1;
                if (partY1 < fullY1)
                    partY1 = fullY1;
                partX2 = pbox->x2;
                if (partX2 > fullX2)
                    partX2 = fullX2;
                partY2 = pbox->y2;
                if (partY2 > fullY2)
                    partY2 = fullY2;

                pbox++;

                if (partX1 < partX2 && partY1 < partY2) {
                    (*pExaScr->info->Solid) (pPixmap,
                                             partX1 + xoff, partY1 + yoff,
                                             partX2 + xoff, partY2 + yoff);
                }
            }
        }
    }
    (*pExaScr->info->DoneSolid) (pPixmap);
    exaMarkSync(pDrawable->pScreen);

 out:
    RegionUninit(pReg);
    RegionDestroy(pReg);
}

const GCOps exaOps = {
    exaFillSpans,
    ExaCheckSetSpans,
    exaPutImage,
    exaCopyArea,
    ExaCheckCopyPlane,
    exaPolyPoint,
    exaPolylines,
    exaPolySegment,
    miPolyRectangle,
    ExaCheckPolyArc,
    miFillPolygon,
    exaPolyFillRect,
    miPolyFillArc,
    miPolyText8,
    miPolyText16,
    miImageText8,
    miImageText16,
    ExaCheckImageGlyphBlt,
    ExaCheckPolyGlyphBlt,
    ExaCheckPushPixels,
};

void
exaCopyWindow(WindowPtr pWin, DDXPointRec ptOldOrg, RegionPtr prgnSrc)
{
    RegionRec rgnDst;
    int dx, dy;
    PixmapPtr pPixmap = (*pWin->drawable.pScreen->GetWindowPixmap) (pWin);

    ExaScreenPriv(pWin->drawable.pScreen);

    dx = ptOldOrg.x - pWin->drawable.x;
    dy = ptOldOrg.y - pWin->drawable.y;
    RegionTranslate(prgnSrc, -dx, -dy);

    RegionInit(&rgnDst, NullBox, 0);

    RegionIntersect(&rgnDst, &pWin->borderClip, prgnSrc);
#ifdef COMPOSITE
    if (pPixmap->screen_x || pPixmap->screen_y)
        RegionTranslate(&rgnDst, -pPixmap->screen_x, -pPixmap->screen_y);
#endif

    if (pExaScr->fallback_counter) {
        pExaScr->fallback_flags |= EXA_FALLBACK_COPYWINDOW;
        goto fallback;
    }

    pExaScr->fallback_flags |= EXA_ACCEL_COPYWINDOW;
    miCopyRegion(&pPixmap->drawable, &pPixmap->drawable,
                 NULL, &rgnDst, dx, dy, exaCopyNtoN, 0, NULL);
    pExaScr->fallback_flags &= ~EXA_ACCEL_COPYWINDOW;

 fallback:
    RegionUninit(&rgnDst);

    if (pExaScr->fallback_flags & EXA_FALLBACK_COPYWINDOW) {
        pExaScr->fallback_flags &= ~EXA_FALLBACK_COPYWINDOW;
        RegionTranslate(prgnSrc, dx, dy);
        ExaCheckCopyWindow(pWin, ptOldOrg, prgnSrc);
    }
}

static Bool
exaFillRegionSolid(DrawablePtr pDrawable, RegionPtr pRegion, Pixel pixel,
                   CARD32 planemask, CARD32 alu, Bool hasClientClip)
{
    ExaScreenPriv(pDrawable->pScreen);
    PixmapPtr pPixmap = exaGetDrawablePixmap(pDrawable);

    ExaPixmapPriv(pPixmap);
    int xoff, yoff;
    Bool ret = FALSE;

    exaGetDrawableDeltas(pDrawable, pPixmap, &xoff, &yoff);
    RegionTranslate(pRegion, xoff, yoff);

    if (pExaScr->fallback_counter || pExaPixmap->accel_blocked)
        goto out;

    if (pExaScr->do_migration) {
        ExaMigrationRec pixmaps[1];

        pixmaps[0].as_dst = TRUE;
        pixmaps[0].as_src = FALSE;
        pixmaps[0].pPix = pPixmap;
        pixmaps[0].pReg = exaGCReadsDestination(pDrawable, planemask, FillSolid,
                                                alu,
                                                hasClientClip) ? NULL : pRegion;

        exaDoMigration(pixmaps, 1, TRUE);
    }

    if (exaPixmapHasGpuCopy(pPixmap) &&
        (*pExaScr->info->PrepareSolid) (pPixmap, alu, planemask, pixel)) {
        int nbox;
        BoxPtr pBox;

        nbox = RegionNumRects(pRegion);
        pBox = RegionRects(pRegion);

        while (nbox--) {
            (*pExaScr->info->Solid) (pPixmap, pBox->x1, pBox->y1, pBox->x2,
                                     pBox->y2);
            pBox++;
        }
        (*pExaScr->info->DoneSolid) (pPixmap);
        exaMarkSync(pDrawable->pScreen);

        if (pExaPixmap->pDamage &&
            pExaPixmap->sys_ptr && pDrawable->type == DRAWABLE_PIXMAP &&
            pDrawable->width == 1 && pDrawable->height == 1 &&
            pDrawable->bitsPerPixel != 24) {
            RegionPtr pending_damage = DamagePendingRegion(pExaPixmap->pDamage);

            switch (pDrawable->bitsPerPixel) {
            case 32:
                *(CARD32 *) pExaPixmap->sys_ptr = pixel;
                break;
            case 16:
                *(CARD16 *) pExaPixmap->sys_ptr = pixel;
                break;
            case 8:
            case 4:
            case 1:
                *(CARD8 *) pExaPixmap->sys_ptr = pixel;
            }

            RegionUnion(&pExaPixmap->validSys, &pExaPixmap->validSys, pRegion);
            RegionUnion(&pExaPixmap->validFB, &pExaPixmap->validFB, pRegion);
            RegionSubtract(pending_damage, pending_damage, pRegion);
        }

        ret = TRUE;
    }

 out:
    RegionTranslate(pRegion, -xoff, -yoff);

    return ret;
}

/* Try to do an accelerated tile of the pTile into pRegion of pDrawable.
 * Based on fbFillRegionTiled(), fbTile().
 */
Bool
exaFillRegionTiled(DrawablePtr pDrawable, RegionPtr pRegion, PixmapPtr pTile,
                   DDXPointPtr pPatOrg, CARD32 planemask, CARD32 alu,
                   Bool hasClientClip)
{
    ExaScreenPriv(pDrawable->pScreen);
    PixmapPtr pPixmap;
    ExaPixmapPrivPtr pExaPixmap;
    ExaPixmapPrivPtr pTileExaPixmap = ExaGetPixmapPriv(pTile);
    int xoff, yoff;
    int tileWidth, tileHeight;
    int nbox = RegionNumRects(pRegion);
    BoxPtr pBox = RegionRects(pRegion);
    Bool ret = FALSE;
    int i;

    tileWidth = pTile->drawable.width;
    tileHeight = pTile->drawable.height;

    /* If we're filling with a solid color, grab it out and go to
     * FillRegionSolid, saving numerous copies.
     */
    if (tileWidth == 1 && tileHeight == 1)
        return exaFillRegionSolid(pDrawable, pRegion,
                                  exaGetPixmapFirstPixel(pTile), planemask,
                                  alu, hasClientClip);

    pPixmap = exaGetDrawablePixmap(pDrawable);
    pExaPixmap = ExaGetPixmapPriv(pPixmap);

    if (pExaScr->fallback_counter || pExaPixmap->accel_blocked ||
        pTileExaPixmap->accel_blocked)
        return FALSE;

    if (pExaScr->do_migration) {
        ExaMigrationRec pixmaps[2];

        pixmaps[0].as_dst = TRUE;
        pixmaps[0].as_src = FALSE;
        pixmaps[0].pPix = pPixmap;
        pixmaps[0].pReg = exaGCReadsDestination(pDrawable, planemask, FillTiled,
                                                alu,
                                                hasClientClip) ? NULL : pRegion;
        pixmaps[1].as_dst = FALSE;
        pixmaps[1].as_src = TRUE;
        pixmaps[1].pPix = pTile;
        pixmaps[1].pReg = NULL;

        exaDoMigration(pixmaps, 2, TRUE);
    }

    pPixmap = exaGetOffscreenPixmap(pDrawable, &xoff, &yoff);

    if (!pPixmap || !exaPixmapHasGpuCopy(pTile))
        return FALSE;

    if ((*pExaScr->info->PrepareCopy) (pTile, pPixmap, 1, 1, alu, planemask)) {
        if (xoff || yoff)
            RegionTranslate(pRegion, xoff, yoff);

        for (i = 0; i < nbox; i++) {
            int height = pBox[i].y2 - pBox[i].y1;
            int dstY = pBox[i].y1;
            int tileY;

            if (alu == GXcopy)
                height = min(height, tileHeight);

            modulus(dstY - yoff - pDrawable->y - pPatOrg->y, tileHeight, tileY);

            while (height > 0) {
                int width = pBox[i].x2 - pBox[i].x1;
                int dstX = pBox[i].x1;
                int tileX;
                int h = tileHeight - tileY;

                if (alu == GXcopy)
                    width = min(width, tileWidth);

                if (h > height)
                    h = height;
                height -= h;

                modulus(dstX - xoff - pDrawable->x - pPatOrg->x, tileWidth,
                        tileX);

                while (width > 0) {
                    int w = tileWidth - tileX;

                    if (w > width)
                        w = width;
                    width -= w;

                    (*pExaScr->info->Copy) (pPixmap, tileX, tileY, dstX, dstY,
                                            w, h);
                    dstX += w;
                    tileX = 0;
                }
                dstY += h;
                tileY = 0;
            }
        }
        (*pExaScr->info->DoneCopy) (pPixmap);

        /* With GXcopy, we only need to do the basic algorithm up to the tile
         * size; then, we can just keep doubling the destination in each
         * direction until it fills the box. This way, the number of copy
         * operations is O(log(rx)) + O(log(ry)) instead of O(rx * ry), where
         * rx/ry is the ratio between box and tile width/height. This can make
         * a big difference if each driver copy incurs a significant constant
         * overhead.
         */
        if (alu != GXcopy)
            ret = TRUE;
        else {
            Bool more_copy = FALSE;

            for (i = 0; i < nbox; i++) {
                int dstX = pBox[i].x1 + tileWidth;
                int dstY = pBox[i].y1 + tileHeight;

                if ((dstX < pBox[i].x2) || (dstY < pBox[i].y2)) {
                    more_copy = TRUE;
                    break;
                }
            }

            if (more_copy == FALSE)
                ret = TRUE;

            if (more_copy && (*pExaScr->info->PrepareCopy) (pPixmap, pPixmap,
                                                            1, 1, alu,
                                                            planemask)) {
                for (i = 0; i < nbox; i++) {
                    int dstX = pBox[i].x1 + tileWidth;
                    int dstY = pBox[i].y1 + tileHeight;
                    int width = min(pBox[i].x2 - dstX, tileWidth);
                    int height = min(pBox[i].y2 - pBox[i].y1, tileHeight);

                    while (dstX < pBox[i].x2) {
                        (*pExaScr->info->Copy) (pPixmap, pBox[i].x1, pBox[i].y1,
                                                dstX, pBox[i].y1, width,
                                                height);
                        dstX += width;
                        width = min(pBox[i].x2 - dstX, width * 2);
                    }

                    width = pBox[i].x2 - pBox[i].x1;
                    height = min(pBox[i].y2 - dstY, tileHeight);

                    while (dstY < pBox[i].y2) {
                        (*pExaScr->info->Copy) (pPixmap, pBox[i].x1, pBox[i].y1,
                                                pBox[i].x1, dstY, width,
                                                height);
                        dstY += height;
                        height = min(pBox[i].y2 - dstY, height * 2);
                    }
                }

                (*pExaScr->info->DoneCopy) (pPixmap);

                ret = TRUE;
            }
        }

        exaMarkSync(pDrawable->pScreen);

        if (xoff || yoff)
            RegionTranslate(pRegion, -xoff, -yoff);
    }

    return ret;
}

/**
 * Accelerates GetImage for solid ZPixmap downloads from framebuffer memory.
 *
 * This is probably the only case we actually care about.  The rest fall through
 * to migration and fbGetImage, which hopefully will result in migration pushing
 * the pixmap out of framebuffer.
 */
void
exaGetImage(DrawablePtr pDrawable, int x, int y, int w, int h,
            unsigned int format, unsigned long planeMask, char *d)
{
    ExaScreenPriv(pDrawable->pScreen);
    PixmapPtr pPix = exaGetDrawablePixmap(pDrawable);

    ExaPixmapPriv(pPix);
    int xoff, yoff;
    Bool ok;

    if (pExaScr->fallback_counter || pExaScr->swappedOut)
        goto fallback;

    /* If there's a system copy, we want to save the result there */
    if (pExaPixmap->pDamage)
        goto fallback;

    pPix = exaGetOffscreenPixmap(pDrawable, &xoff, &yoff);

    if (pPix == NULL || pExaScr->info->DownloadFromScreen == NULL)
        goto fallback;

    /* Only cover the ZPixmap, solid copy case. */
    if (format != ZPixmap || !EXA_PM_IS_SOLID(pDrawable, planeMask))
        goto fallback;

    /* Only try to handle the 8bpp and up cases, since we don't want to think
     * about <8bpp.
     */
    if (pDrawable->bitsPerPixel < 8)
        goto fallback;

    ok = pExaScr->info->DownloadFromScreen(pPix, pDrawable->x + x + xoff,
                                           pDrawable->y + y + yoff, w, h, d,
                                           PixmapBytePad(w, pDrawable->depth));
    if (ok) {
        exaWaitSync(pDrawable->pScreen);
        return;
    }

 fallback:
    ExaCheckGetImage(pDrawable, x, y, w, h, format, planeMask, d);
}
