qregion_qws.cpp

qt-embedded-2.3.8.tar.gz源码

    if ((pReg->numRects != 0) &&  \
	(pNextRect[-1].top() == y1) &&  \
	(pNextRect[-1].bottom() == y2) &&  \
	(pNextRect[-1].right() >= r->left()-1))  \
    {  \
	if (pNextRect[-1].right() < r->right())  \
	{  \
	    pNextRect[-1].setRight( r->right() );  \
	    ASSERT(pNextRect[-1].left() <= pNextRect[-1].right()); \
	}  \
    }  \
    else  \
    {  \
	MEMCHECK(pReg, pNextRect, pReg->rects)  \
	pNextRect->setCoords( r->left(), y1, r->right(), y2 ); \
	pReg->numRects++;  \
        pNextRect++;  \
    }  \
    r++;

    ASSERT (y1<=y2);
    while ((r1 != r1End) && (r2 != r2End))
    {
	if (r1->left() < r2->left())
	{
	    MERGERECT(r1)
	}
	else
	{
	    MERGERECT(r2)
	}
    }

    if (r1 != r1End)
    {
	do
	{
	    MERGERECT(r1)
	} while (r1 != r1End);
    }
    else while (r2 != r2End)
    {
	MERGERECT(r2)
    }
    return 0;	/* lint */
}

static
int
XUnionRegion(Region reg1, Region reg2, Region newReg)
{
    /*  checks all the simple cases */

    /*
     * Region 1 and 2 are the same or region 1 is empty
     */
    if ( (reg1 == reg2) || (!(reg1->numRects)) )
    {
        if (newReg != reg2)
            miRegionCopy(newReg, reg2);
        return 1;
    }

    /*
     * if nothing to union (region 2 empty)
     */
    if (!(reg2->numRects))
    {
        if (newReg != reg1)
            miRegionCopy(newReg, reg1);
        return 1;
    }

    /*
     * Region 1 completely subsumes region 2
     */
    if ((reg1->numRects == 1) &&
	(reg1->extents.left() <= reg2->extents.left()) &&
	(reg1->extents.top() <= reg2->extents.top()) &&
	(reg1->extents.right() >= reg2->extents.right()) &&
	(reg1->extents.bottom() >= reg2->extents.bottom()))
    {
        if (newReg != reg1)
            miRegionCopy(newReg, reg1);
        return 1;
    }

    /*
     * Region 2 completely subsumes region 1
     */
    if ((reg2->numRects == 1) &&
	(reg2->extents.left() <= reg1->extents.left()) &&
	(reg2->extents.top() <= reg1->extents.top()) &&
	(reg2->extents.right() >= reg1->extents.right()) &&
	(reg2->extents.bottom() >= reg1->extents.bottom()))
    {
        if (newReg != reg2)
            miRegionCopy(newReg, reg2);
        return 1;
    }

    miRegionOp (newReg, reg1, reg2, (voidProcp) miUnionO,
    		(voidProcp) miUnionNonO, (voidProcp) miUnionNonO);

    newReg->extents.setLeft( QMIN(reg1->extents.left(), reg2->extents.left()) );
    newReg->extents.setTop( QMIN(reg1->extents.top(), reg2->extents.top()) );
    newReg->extents.setRight( QMAX(reg1->extents.right(), reg2->extents.right()) );
    newReg->extents.setBottom( QMAX(reg1->extents.bottom(), reg2->extents.bottom()) );

    return 1;
}


/*======================================================================
 * 	    	  Region Subtraction
 *====================================================================*/

/*-
 *-----------------------------------------------------------------------
 * miSubtractNonO --
 *	Deal with non-overlapping band for subtraction. Any parts from
 *	region 2 we discard. Anything from region 1 we add to the region.
 *
 * Results:
 *	None.
 *
 * Side Effects:
 *	pReg may be affected.
 *
 *-----------------------------------------------------------------------
 */
/* static void*/
static
int
miSubtractNonO1 (register Region pReg, register QRect *r,
		 QRect *rEnd, register int y1, register int y2)
{
    register QRect *pNextRect;
	
    pNextRect = pReg->rects.data() + pReg->numRects;
	
    ASSERT(y1<=y2);

    while (r != rEnd)
    {
	ASSERT(r->left()<=r->right());
	MEMCHECK(pReg, pNextRect, pReg->rects)
	pNextRect->setCoords( r->left(), y1, r->right(), y2 );
	pReg->numRects++;
	pNextRect++;

	r++;
    }
    return 0;	/* lint */
}

/*-
 *-----------------------------------------------------------------------
 * miSubtractO --
 *	Overlapping band subtraction. x1 is the left-most point not yet
 *	checked.
 *
 * Results:
 *	None.
 *
 * Side Effects:
 *	pReg may have rectangles added to it.
 *
 *-----------------------------------------------------------------------
 */
/* static void*/
static
int
miSubtractO (register Region pReg, register QRect *r1, QRect *r1End,
	     register QRect *r2, QRect *r2End, register int y1, register int y2)
{
    register QRect *pNextRect;
    register int  	x1;

    x1 = r1->left();

    ASSERT(y1<=y2);
    pNextRect = pReg->rects.data() + pReg->numRects;

    while ((r1 != r1End) && (r2 != r2End))
    {
	if (r2->right() < x1)
	{
	    /*
	     * Subtrahend missed the boat: go to next subtrahend.
	     */
	    r2++;
	}
	else if (r2->left() <= x1)
	{
	    /*
	     * Subtrahend precedes minuend: nuke left edge of minuend.
	     */
	    x1 = r2->right()+1;
	    if (x1 > r1->right())
	    {
		/*
		 * Minuend completely covered: advance to next minuend and
		 * reset left fence to edge of new minuend.
		 */
		r1++;
		if (r1 != r1End)
		    x1 = r1->left();
	    }
	    else
	    {
		/*
		 * Subtrahend now used up since it doesn't extend beyond
		 * minuend
		 */
		r2++;
	    }
	}
	else if (r2->left() <= r1->right())
	{
	    /*
	     * Left part of subtrahend covers part of minuend: add uncovered
	     * part of minuend to region and skip to next subtrahend.
	     */
	    ASSERT(x1<r2->left());
	    MEMCHECK(pReg, pNextRect, pReg->rects)
	    pNextRect->setCoords( x1, y1, r2->left() - 1, y2 );
	    pReg->numRects++;
	    pNextRect++;

	    x1 = r2->right() + 1;
	    if (x1 > r1->right())
	    {
		/*
		 * Minuend used up: advance to new...
		 */
		r1++;
		if (r1 != r1End)
		    x1 = r1->left();
	    }
	    else
	    {
		/*
		 * Subtrahend used up
		 */
		r2++;
	    }
	}
	else
	{
	    /*
	     * Minuend used up: add any remaining piece before advancing.
	     */
	    if (r1->right() >= x1)
	    {
		MEMCHECK(pReg, pNextRect, pReg->rects)
		pNextRect->setCoords( x1, y1, r1->right(), y2 );
		pReg->numRects++;
		pNextRect++;
	    }
	    r1++;
	    if ( r1 != r1End )
		x1 = r1->left();
	}
    }

    /*
     * Add remaining minuend rectangles to region.
     */
    while (r1 != r1End)
    {
	ASSERT(x1<=r1->right());
	MEMCHECK(pReg, pNextRect, pReg->rects)
	pNextRect->setCoords( x1, y1, r1->right(), y2 );
	pReg->numRects++;
	pNextRect++;

	r1++;
	if (r1 != r1End)
	{
	    x1 = r1->left();
	}
    }
    return 0;	/* lint */
}
	
/*-
 *-----------------------------------------------------------------------
 * miSubtract --
 *	Subtract regS from regM and leave the result in regD.
 *	S stands for subtrahend, M for minuend and D for difference.
 *
 * Results:
 *	TRUE.
 *
 * Side Effects:
 *	regD is overwritten.
 *
 *-----------------------------------------------------------------------
 */

static
int
XSubtractRegion(Region regM, Region regS, register Region regD)
{
   /* check for trivial reject */
    if ( (!(regM->numRects)) || (!(regS->numRects))  ||
	(!EXTENTCHECK(&regM->extents, &regS->extents)) )
    {
	miRegionCopy(regD, regM);
        return 1;
    }

    miRegionOp (regD, regM, regS, (voidProcp) miSubtractO,
    		(voidProcp) miSubtractNonO1, (voidProcp) NULL);

    /*
     * Can't alter newReg's extents before we call miRegionOp because
     * it might be one of the source regions and miRegionOp depends
     * on the extents of those regions being the unaltered. Besides, this
     * way there's no checking against rectangles that will be nuked
     * due to coalescing, so we have to examine fewer rectangles.
     */
    miSetExtents (regD);
    return 1;
}

static
int
XXorRegion( Region sra, Region srb, Region dr )
{
    Region tra, trb;

    if (! (tra = XCreateRegion()))
	return 0;
    if (! (trb = XCreateRegion()))
	return 0;
    (void) XSubtractRegion(sra,srb,tra);
    (void) XSubtractRegion(srb,sra,trb);
    (void) XUnionRegion(tra,trb,dr);
    XDestroyRegion(tra);
    XDestroyRegion(trb);
    return 0;
}

/*
 * Check to see if the region is empty.  Assumes a region is passed
 * as a parameter
 */
static
int
XEmptyRegion( Region r )
{
    if( r->numRects == 0 ) return TRUE;
    else  return FALSE;
}

/*
 *	Check to see if two regions are equal	
 */
static
int
XEqualRegion( Region r1, Region r2 )
{
    int i;

    if( r1->numRects != r2->numRects ) return FALSE;
    else if( r1->numRects == 0 ) return TRUE;
    else if ( r1->extents.left() != r2->extents.left() ) return FALSE;
    else if ( r1->extents.right() != r2->extents.right() ) return FALSE;
    else if ( r1->extents.top() != r2->extents.top() ) return FALSE;
    else if ( r1->extents.bottom() != r2->extents.bottom() ) return FALSE;
    else {
	QRect *rr1 = r1->rects.data();
	QRect *rr2 = r2->rects.data();
	for( i=0; i < r1->numRects; i++, rr1++, rr2++ ) {
	    if ( rr1->left() != rr2->left() ) return FALSE;
	    else if ( rr1->right() != rr2->right() ) return FALSE;
	    else if ( rr1->top() != rr2->top() ) return FALSE;
	    else if ( rr1->bottom() != rr2->bottom() ) return FALSE;
	}
    }
    return TRUE;
}

static
int
XPointInRegion( Region pRegion, int x, int y )
{
    int i;

    if (pRegion->numRects == 0)
        return FALSE;
    if (!pRegion->extents.contains(x, y))
        return FALSE;
    for (i=0; i<pRegion->numRects; i++)
    {
        if (pRegion->rects[i].contains(x, y))
	    return TRUE;
    }
    return FALSE;
}

static
int
XRectInRegion(register Region region,
	    int rx, int ry, unsigned int rwidth, unsigned int rheight)
{
    register QRect *pbox;
    register QRect *pboxEnd;
    QRect rect(rx, ry, rwidth, rheight);
    register QRect *prect = &rect;
    int      partIn, partOut;

    /* this is (just) a useful optimization */
    if ((region->numRects == 0) || !EXTENTCHECK(&region->extents, prect))
        return(RectangleOut);

    partOut = FALSE;
    partIn = FALSE;

    /* can stop when both partOut and partIn are TRUE, or we reach prect->y2 */
    for (pbox = region->rects.data(), pboxEnd = pbox + region->numRects;
	 pbox < pboxEnd;
	 pbox++)
    {

	if (pbox->bottom() < ry)
	   continue;	/* getting up to speed or skipping remainder of band */

	if (pbox->top() > ry)
	{
	   partOut = TRUE;	/* missed part of rectangle above */
	   if (partIn || (pbox->top() > prect->bottom()))
	      break;
	   ry = pbox->top();	/* x guaranteed to be == prect->x1 */
	}