/* $XFree86: xc/programs/Xserver/hw/xfree86/xaa/xaaDashLine.c,v 1.4 2001/10/28 03:34:04 tsi Exp $ */

#include "X.h"
#include "misc.h"
#include "xf86.h"
#include "xf86_ansic.h"
#include "xf86_OSproc.h"

#include "scrnintstr.h"
#include "pixmapstr.h"
#include "miline.h"
#include "xf86str.h"
#include "xaa.h"
#include "xaalocal.h"


void
#ifdef POLYSEGMENT
XAAPolySegmentDashed(
    DrawablePtr	pDrawable,
    GCPtr	pGC,
    int		nseg,
    xSegment	*pSeg
#else
XAAPolyLinesDashed(
    DrawablePtr pDrawable,
    GCPtr	pGC,
    int		mode,		/* Origin or Previous */
    int		npt,		/* number of points */
    DDXPointPtr pptInit
#endif
){
    XAAInfoRecPtr infoRec = GET_XAAINFORECPTR_FROM_GC(pGC);
    XAAGCPtr   pGCPriv = (XAAGCPtr) (pGC)->devPrivates[XAAGCIndex].ptr;
    BoxPtr pboxInit = REGION_RECTS(pGC->pCompositeClip);
    int nboxInit = REGION_NUM_RECTS(pGC->pCompositeClip);
    unsigned int bias = miGetZeroLineBias(pDrawable->pScreen);
    int xorg = pDrawable->x;
    int yorg = pDrawable->y;
    int nbox;
    BoxPtr pbox;
#ifndef POLYSEGMENT
    DDXPointPtr ppt;
#endif
    unsigned int oc1, oc2;
    int dmin, dmaj, e, octant;
    int x1, x2, y1, y2, tmp, len, offset;
    int PatternLength, PatternOffset;

    if(!nboxInit)
	return;

    if (infoRec->DashedLineFlags & LINE_LIMIT_COORDS) {
	int minValX = infoRec->DashedLineLimits.x1;
	int maxValX = infoRec->DashedLineLimits.x2;
	int minValY = infoRec->DashedLineLimits.y1;
	int maxValY = infoRec->DashedLineLimits.y2;
#ifdef POLYSEGMENT
	int n = nseg;
	xSegment *s = pSeg;

	while (n--)
#else
	int n = npt;
	int xorgtmp = xorg;
	int yorgtmp = yorg;

	ppt = pptInit;
	x2 = ppt->x + xorgtmp;
	y2 = ppt->y + yorgtmp;
	while (--n)
#endif
	{
#ifdef POLYSEGMENT
	    x1 = s->x1 + xorg;
	    y1 = s->y1 + yorg;
	    x2 = s->x2 + xorg;
	    y2 = s->y2 + yorg;
	    s++;
#else
	    x1 = x2;
	    y1 = y2;
	    ++ppt;
	    if (mode == CoordModePrevious) {
		xorgtmp = x1;
		yorgtmp = y1;
	    }
	    x2 = ppt->x + xorgtmp;
	    y2 = ppt->y + yorgtmp;
#endif
	    if (x1 > maxValX || x1 < minValX ||
		x2 > maxValX || x2 < minValX ||
		y1 > maxValY || y1 < minValY ||
		y2 > maxValY || y2 < minValY) {
#ifdef POLYSEGMENT
		XAAFallbackOps.PolySegment(pDrawable, pGC, nseg, pSeg);
#else
		XAAFallbackOps.Polylines(pDrawable, pGC, mode, npt, pptInit);
#endif
		return;
	    }
	}
    }

    PatternLength = pGCPriv->DashLength; 
    PatternOffset = pGC->dashOffset % PatternLength;

    (*infoRec->SetupForDashedLine)(infoRec->pScrn, pGC->fgPixel,
		(pGC->lineStyle == LineDoubleDash) ? pGC->bgPixel : -1,
		pGC->alu, pGC->planemask, PatternLength, pGCPriv->DashPattern);


#ifdef POLYSEGMENT
    while (nseg--)
#else
    ppt = pptInit;
    x2 = ppt->x + xorg;
    y2 = ppt->y + yorg;
    while(--npt)
#endif
    {
	nbox = nboxInit;
	pbox = pboxInit;

#ifdef POLYSEGMENT
	x1 = pSeg->x1 + xorg;	
	y1 = pSeg->y1 + yorg;
	x2 = pSeg->x2 + xorg;	
	y2 = pSeg->y2 + yorg;
	pSeg++;
#else
	x1 = x2; 
	y1 = y2;
	++ppt;
	if (mode == CoordModePrevious) {
	    xorg = x1; 
	    yorg = y1;
	}
	x2 = ppt->x + xorg; 
	y2 = ppt->y + yorg;
#endif


	if (infoRec->SubsequentDashedBresenhamLine) {
	    if((dmaj = x2 - x1) < 0) {
		dmaj = -dmaj;
		octant = XDECREASING;
	    } else octant = 0;		   

	    if((dmin = y2 - y1) < 0) {
		dmin = -dmin;
		octant |= YDECREASING;
	    }	
	
	    if(dmin >= dmaj){
		tmp = dmin; dmin = dmaj; dmaj = tmp;
		octant |= YMAJOR;
	    }

	    e = -dmaj - ((bias >> octant) & 1);
	    len = dmaj;
	    dmin <<= 1;
	    dmaj <<= 1;
	} else {	/* Muffle compiler */
	    dmin = dmaj = e = octant = len = 0;
	}

	while(nbox--) {
	    oc1 = oc2 = 0;
	    OUTCODES(oc1, x1, y1, pbox);
	    OUTCODES(oc2, x2, y2, pbox);
	    if (!(oc1 | oc2)) {   /* uncliped */
		if(infoRec->SubsequentDashedTwoPointLine) {
		   (*infoRec->SubsequentDashedTwoPointLine)(
				infoRec->pScrn, x1, y1, x2, y2, 
#ifdef POLYSEGMENT
			    	(pGC->capStyle != CapNotLast) ? 0 :
#endif
				OMIT_LAST, PatternOffset);
		} else {
		    (*infoRec->SubsequentDashedBresenhamLine)(
				infoRec->pScrn, x1, y1, dmaj, dmin, e, 
#ifdef POLYSEGMENT
			    	(pGC->capStyle != CapNotLast) ? (len+1) :
#endif
			    	len, octant, PatternOffset);
		}
		break;
	    } else if (oc1 & oc2) { /* completely clipped */
		pbox++;
	    } else if (infoRec->ClippingFlags & HARDWARE_CLIP_DASHED_LINE) {
		(*infoRec->SetClippingRectangle)(infoRec->pScrn,
			pbox->x1, pbox->y1, pbox->x2 - 1, pbox->y2 - 1);

		if(infoRec->SubsequentDashedBresenhamLine) {
		    (*infoRec->SubsequentDashedBresenhamLine)(
				infoRec->pScrn, x1, y1, dmaj, dmin, e, 
#ifdef POLYSEGMENT
			    	(pGC->capStyle != CapNotLast) ? (len+1) :
#endif
			    	len, octant, PatternOffset);
		} else {
			(*infoRec->SubsequentDashedTwoPointLine)(
				infoRec->pScrn, x1, y1, x2, y2, 
#ifdef POLYSEGMENT
			    	(pGC->capStyle != CapNotLast) ? 0 :
#endif
				OMIT_LAST, PatternOffset
			);
		}
		(*infoRec->DisableClipping)(infoRec->pScrn);
		pbox++;
	    } else {
		int new_x1 = x1, new_y1 = y1, new_x2 = x2, new_y2 = y2;
		int clip1 = 0, clip2 = 0;
		int err, adx, ady;
		    
		if(octant & YMAJOR) {
		    ady = dmaj >> 1;
		    adx = dmin >> 1;
		} else {
		    ady = dmin >> 1;
		    adx = dmaj >> 1;
		}

		if (miZeroClipLine(pbox->x1, pbox->y1, 
				       pbox->x2 - 1, pbox->y2 - 1,
				       &new_x1, &new_y1, &new_x2, &new_y2,
				       adx, ady, &clip1, &clip2,
				       octant, bias, oc1, oc2) == -1)
		{
		    pbox++;
		    continue;
		}

		if (octant & YMAJOR)
		    len = abs(new_y2 - new_y1);
		else
		    len = abs(new_x2 - new_x1);
#ifdef POLYSEGMENT
		if (clip2 != 0 || pGC->capStyle != CapNotLast)
		    len++;
#else
		len += (clip2 != 0);
#endif
		if (len) {
		    int abserr, clipdx, clipdy;
			/* unwind bresenham error term to first point */
		    if (clip1) {
			clipdx = abs(new_x1 - x1);
			clipdy = abs(new_y1 - y1);

			if (octant & YMAJOR)
			    err = e + clipdy*dmin - clipdx*dmaj;
			else
			    err = e + clipdx*dmin - clipdy*dmaj;
		    } else
			err = e;

#define range infoRec->DashedBresenhamLineErrorTermBits
		    abserr = abs(err);			    
		    while((abserr & range) || 
			  (dmaj & range) ||
			  (dmin & range)) {
			dmin >>= 1;
			dmaj >>= 1;
			abserr >>= 1;
			err /= 2;
		    }

		    if(octant & YMAJOR)
			offset = abs(new_y1 - y1);
		    else 
			offset = abs(new_x1 - x1);

		    offset += PatternOffset;
		    offset %= PatternLength;

		    (*infoRec->SubsequentDashedBresenhamLine)(
				infoRec->pScrn, new_x1, new_y1,
				dmaj, dmin, err, len, octant, offset);
		}
		pbox++;
	    }
	} /* while (nbox--) */
#ifndef POLYSEGMENT
	len = abs(y2 - y1);
	tmp = abs(x2 - x1);
	PatternOffset += (len > tmp) ? len : tmp;
	PatternOffset %= PatternLength;
#endif
    } /* while (nline--) */

#ifndef POLYSEGMENT
    /* paint the last point if the end style isn't CapNotLast.
       (Assume that a projecting, butt, or round cap that is one
        pixel wide is the same as the single pixel of the endpoint.)
    */

    if ((pGC->capStyle != CapNotLast) &&
	((ppt->x + xorg != pptInit->x + pDrawable->x) ||
	 (ppt->y + yorg != pptInit->y + pDrawable->y) ||
	 (ppt == pptInit + 1)))
    {
	nbox = nboxInit;
	pbox = pboxInit;
	while (nbox--) {
	    if ((x2 >= pbox->x1) && (y2 >= pbox->y1) &&
		(x2 <  pbox->x2) && (y2 <  pbox->y2))
	    {
		if(infoRec->SubsequentDashedTwoPointLine) {
			(*infoRec->SubsequentDashedTwoPointLine)(
				infoRec->pScrn, x2, y2, x2, y2, 0,
				PatternOffset);
		} else {
			(*infoRec->SubsequentDashedBresenhamLine)(
				infoRec->pScrn, x2, y2, 2, 0, -1, 
				1, 0, PatternOffset);
		}
		break;
	    } else
		pbox++;
	}
    }
#endif

    SET_SYNC_FLAG(infoRec);
}

