/*** $Id: cliprect.c,v 1.5 2004/04/01 08:57:13 weiym Exp $** ** cliprect.c: the Clip Rect module.** ** Copyright (C) 2003 Feynman Software.** Copyright (C) 1999 ~ 2002, Wei Yongming**** Current maintainer: Wei Yongming.**** Create date: 1999/3/26 by Wei Yongming.*//*** This program is free software; you can redistribute it and/or modify** it under the terms of the GNU General Public License as published by** the Free Software Foundation; either version 2 of the License, or** (at your option) any later version.**** This program 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 General Public License for more details.**** You should have received a copy of the GNU General Public License** along with this program; if not, write to the Free Software** Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA*//*** TODO:*/ #include <stdio.h>#include <stdlib.h>#include <errno.h>#include "common.h"#include "gdi.h"#include "cliprect.h"#include "gal.h"#include "blockheap.h"/************************** clip region operation ****************************/static void EvaluateBoundRect (PCLIPRGN pRgn){    PCLIPRECT pCRect, pTemp;    pCRect = pRgn->head;    if (pCRect == NULL) {        SetRectEmpty (&pRgn->rcBound);        return;    }    pRgn->rcBound = pCRect->rc;    pCRect = pCRect->next;    while (pCRect) {        if(pRgn->rcBound.left > pCRect->rc.left)            pRgn->rcBound.left = pCRect->rc.left;           if(pRgn->rcBound.top > pCRect->rc.top)            pRgn->rcBound.top = pCRect->rc.top;        if(pRgn->rcBound.right < pCRect->rc.right)            pRgn->rcBound.right = pCRect->rc.right;        if(pRgn->rcBound.bottom < pCRect->rc.bottom)            pRgn->rcBound.bottom = pCRect->rc.bottom;        pCRect = pCRect->next;    }    // Remove empty clip rects.    pCRect = pRgn->head;    while (pCRect->next) {        if (IsRectEmpty (&pCRect->next->rc)) {            pTemp = pCRect->next;            pCRect->next = pTemp->next;            FreeClipRect (pRgn->heap, pTemp);        }        else            pCRect = pCRect->next;    }    pRgn->tail = pCRect;    if (IsRectEmpty (&pRgn->head->rc)) {        pTemp = pRgn->head;        pRgn->head = pTemp->next;        FreeClipRect (pRgn->heap, pTemp);    }}void GUIAPI InitClipRgn (PCLIPRGN pRgn, PBLOCKHEAP heap){     SetRectEmpty (&pRgn->rcBound);     pRgn->head = NULL;     pRgn->tail = NULL;     pRgn->heap = heap;   // read-only field.}void GUIAPI GetClipRgnBoundRect (PCLIPRGN pRgn, PRECT pRect){     *pRect = pRgn->rcBound;}/* return TRUE if point is in region */BOOL GUIAPI PtInRegion (PCLIPRGN region, int x, int y){    PCLIPRECT cliprect = region->head;    /* check with bounding rect of clipping region */    if (!PtInRect (&region->rcBound, x, y))        return FALSE;    /* find the ban in which this point lies */    cliprect = region->head;    while (cliprect) {        if (PtInRect (&cliprect->rc, x, y))            return TRUE;        cliprect = cliprect->next;    }    return FALSE;}/* Returns TRUE if rect is at least partly inside region */BOOL GUIAPI RectInRegion (PCLIPRGN region, const RECT* rect){    PCLIPRECT cliprect = region->head;    /* check with bounding rect of clipping region */    if (!DoesIntersect (&region->rcBound, rect))        return FALSE;    /* find the ban in which this point lies */    cliprect = region->head;    while (cliprect) {        if (DoesIntersect (&cliprect->rc, rect))            return TRUE;        cliprect = cliprect->next;    }    return FALSE;}void GUIAPI OffsetRegion (PCLIPRGN region, int x, int y){    CLIPRECT* cliprect = region->head;    while (cliprect) {        OffsetRect (&cliprect->rc, x, y);        cliprect = cliprect->next;    }    if (region->head) {        OffsetRect (&region->rcBound, x, y);    }}BOOL GUIAPI SetClipRgn (PCLIPRGN pRgn, const RECT* pRect){    PCLIPRECT pClipRect;    RECT rcTemp;    rcTemp = *pRect;    if (IsRectEmpty (&rcTemp))        return FALSE;    NormalizeRect (&rcTemp);    // empty rgn first    EmptyClipRgn (pRgn);    // get a new clip rect from free list    pClipRect = ClipRectAlloc (pRgn->heap);    // set clip rect    pClipRect->rc = rcTemp;    pClipRect->next = NULL;    pRgn->head = pRgn->tail = pClipRect;    pRgn->rcBound = rcTemp;    return TRUE;} BOOL GUIAPI IsEmptyClipRgn (const CLIPRGN* pRgn){     if (pRgn->head == NULL)         return TRUE;     return FALSE;}void GUIAPI EmptyClipRgn (PCLIPRGN pRgn){     PCLIPRECT pCRect, pTemp;     pCRect = pRgn->head;     while (pCRect) {         pTemp = pCRect->next;         FreeClipRect (pRgn->heap, pCRect);         pCRect = pTemp;     }     SetRectEmpty (&pRgn->rcBound);     pRgn->head = NULL;     pRgn->tail = NULL;}BOOL GUIAPI ClipRgnCopy (PCLIPRGN pDstRgn, const CLIPRGN* pSrcRgn){    PCLIPRECT pcr;    PCLIPRECT pnewcr;    // return false if the destination region is not a empty one.    if (pDstRgn->head) return FALSE;    if (!(pcr = pSrcRgn->head)) return TRUE;    pnewcr = ClipRectAlloc (pDstRgn->heap);    pDstRgn->head = pnewcr;    pnewcr->rc = pcr->rc;    while (pcr->next) {       pcr = pcr->next;       pnewcr->next = ClipRectAlloc (pDstRgn->heap);       pnewcr = pnewcr->next;       pnewcr->rc = pcr->rc;    }    pnewcr->next = NULL;    pDstRgn->tail = pnewcr;    pDstRgn->rcBound = pSrcRgn->rcBound;     return TRUE;}BOOL GUIAPI ClipRgnIntersect (PCLIPRGN pRstRgn,                        const CLIPRGN* pRgn1, const CLIPRGN* pRgn2){    RECT rc;    PCLIPRECT pnewcr;    PCLIPRECT pcr1, pcr2;    if (pRstRgn->head) return FALSE;    if (!(pcr1 = pRgn1->head)) return TRUE;    if (!(pcr2 = pRgn2->head)) return TRUE;    pnewcr = ClipRectAlloc (pRstRgn->heap);    pnewcr->next = NULL;    pRstRgn->head = pnewcr;    while (pcr1) {        while (pcr2) {            if (IntersectRect (&rc, &pcr1->rc, &pcr2->rc)) {               pnewcr->rc = rc;               pnewcr->next = ClipRectAlloc (pRstRgn->heap);            }            pcr2 = pcr2->next;        }        pcr2 = pRgn2->head;        pcr1 = pcr1->next;    }    pRstRgn->tail = pnewcr;    if (pnewcr->next)    {        FreeClipRect(pRstRgn->heap, pnewcr->next);        pnewcr->next = NULL;    }    EvaluateBoundRect(pRstRgn);    return TRUE;}BOOL GUIAPI AddClipRect (PCLIPRGN pRgn, const RECT* pRect){     PCLIPRECT pClipRect;     RECT rcTemp;     rcTemp = *pRect;     if (IsRectEmpty (&rcTemp))         return FALSE;     NormalizeRect (&rcTemp);     pClipRect = ClipRectAlloc (pRgn->heap);     pClipRect->rc = rcTemp;     pClipRect->next = NULL;     if (pRgn->head) {         pRgn->tail->next = pClipRect;         pRgn->tail = pClipRect;     }     else {         pRgn->head = pRgn->tail = pClipRect;     }     return TRUE;}BOOL GUIAPI IntersectClipRect (PCLIPRGN pRgn, const RECT* pRect){    PCLIPRECT pCRect;    RECT rcTemp;     if (IsRectEmpty (pRect)) {        EmptyClipRgn (pRgn);        return TRUE;    }    rcTemp = *pRect;    NormalizeRect (&rcTemp);    // intersect    pCRect = pRgn->head;    while (pCRect) {        if (!IntersectRect (&pCRect->rc, &pCRect->rc, &rcTemp))            SetRectEmpty(&pCRect->rc);        pCRect = pCRect->next;    }    EvaluateBoundRect (pRgn);    return TRUE;}BOOL GUIAPI SubtractClipRect (PCLIPRGN pRgn, const RECT* pRect){    PCLIPRECT pCRect, pSaved, pTemp;    RECT rc[4], rcTemp, rcInflated;    int nCount;    PRECT src, erc;    int i;    if (IsRectEmpty (pRect))        return FALSE;    rcInflated = *pRect;    erc = &rcInflated;    NormalizeRect (erc);    if (!DoesIntersect(&pRgn->rcBound, erc)) {        return FALSE;    }    pCRect = pRgn->head;    while (pCRect) {        src = &pCRect->rc;        if (!IntersectRect(&rcTemp, src, erc)) {            pCRect = pCRect->next;            continue;        }        pSaved = pCRect->next;        nCount = 0;        if(erc->top > src->top)        {            rc[nCount].left  = src->left;            rc[nCount].top   = src->top;            rc[nCount].right = src->right;            rc[nCount].bottom = erc->top;            nCount++;            src->top = erc->top;        }        if(erc->bottom < src->bottom)        {            rc[nCount].top  = erc->bottom;            rc[nCount].left   = src->left;            rc[nCount].right = src->right;            rc[nCount].bottom = src->bottom;            nCount++;             src->bottom = erc->bottom;        }        if(erc->left > src->left)        {            rc[nCount].left  = src->left;            rc[nCount].top   = src->top;            rc[nCount].right = erc->left;            rc[nCount].bottom = src->bottom;            nCount++;        }        if(erc->right < src->right)        {            rc[nCount].left  = erc->right;            rc[nCount].top   = src->top;            rc[nCount].right = src->right;            rc[nCount].bottom = src->bottom;            nCount++;        }        if (nCount == 0)            SetRectEmpty (&pCRect->rc);        else if(nCount > 0)            pCRect->rc = rc[0];        for(i = 1; i<nCount; i++)        {            pTemp = ClipRectAlloc (pRgn->heap);             pTemp->rc = rc[i];            pCRect->next = pTemp;            pCRect = pTemp;        }        pCRect->next = pSaved;        pCRect = pSaved;    }    EvaluateBoundRect (pRgn);    return TRUE;}