Plan 9 from Bell Labs’s /usr/web/sources/contrib/fgb/root/sys/src/ape/X11/cmd/X/hw/xfree86/xaa/xaaWideLine.c

Copyright © 2021 Plan 9 Foundation.
Distributed under the MIT License.
Download the Plan 9 distribution.


/*

XAAPolylinesWideSolid does not maintain a span list and subsequently does
not follow the "touch-each-pixel-once" rules for wide lines and arcs.
This means it can only be used in the case where we have
miSpansEasyRop(pGC->alu).  Since we clip spans on the fly, we
limited usage of this function to one rect situations. This
function is used only for solid lines. 

  Adapted from miWideLine by Mark Vojkovich ([email protected])
Original mi code written by Keith Packard.

*/

#ifdef HAVE_XORG_CONFIG_H
#include <xorg-config.h>
#endif

#include <math.h>

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

#include <X11/X.h>
#include "windowstr.h"
#include "gcstruct.h"
#include "regionstr.h"
#include "miwideline.h"
#include "mi.h"
#include "xf86str.h"
#include "xaa.h"
#include "xaalocal.h"

#define DRAW_POINT(pScrn, x, y) \
  if(hardClip) (*infoRec->SubsequentSolidFillRect)(pScrn, x, y, 1, 1); \
  else XAAPointHelper(pScrn, x, y)

#define FILL_RECT(pScrn, x, y, w, h) \
  if(hardClip) (*infoRec->SubsequentSolidFillRect)(pScrn, x, y, w, h); \
  else XAAFillRectHelper(pScrn, x, y, w, h)

#define FILL_SPAN(pScrn, x, y, w) \
  if(hardClip) (*infoRec->SubsequentSolidFillRect)(pScrn, x, y, w, 1); \
  else XAASpanHelper(pScrn, x, y, w)


#define CLIPSTEPEDGE(edgey,edge,edgeleft) \
    if (ybase == edgey) { \
	if (edgeleft) { \
	    if (edge->x > xcl) \
		xcl = edge->x; \
	} else { \
	    if (edge->x < xcr) \
		xcr = edge->x; \
	} \
	edgey++; \
	edge->x += edge->stepx; \
	edge->e += edge->dx; \
	if (edge->e > 0) { \
	    edge->x += edge->signdx; \
	    edge->e -= edge->dy; \
	} \
    }

static void 
XAAPointHelper(ScrnInfoPtr pScrn, int x, int y)
{
   XAAInfoRecPtr infoRec = GET_XAAINFORECPTR_FROM_SCRNINFOPTR(pScrn);
   BoxPtr extents = infoRec->ClipBox;

   if((x >= extents->x1) && (x < extents->x2) &&
	(y >= extents->y1) && (y < extents->y2))
	(*infoRec->SubsequentSolidFillRect)(pScrn, x, y, 1, 1);
}

static void 
XAAFillRectHelper(ScrnInfoPtr pScrn, int x1, int y1, int dx, int dy)
{
   XAAInfoRecPtr infoRec = GET_XAAINFORECPTR_FROM_SCRNINFOPTR(pScrn);
   BoxPtr extents = infoRec->ClipBox;
   int x2 = x1 + dx;
   int y2 = y1 + dy;
	
   if(x1 < extents->x1) x1 = extents->x1;
   if(x2 >= extents->x2) x2 = extents->x2;
   if((dx = x2 - x1)<1) return;
   if(y1 < extents->y1) y1 = extents->y1;
   if(y2 >= extents->y2) y2 = extents->y2;
   if((dy = y2 - y1)<1) return;

   (*infoRec->SubsequentSolidFillRect)(pScrn, x1, y1, dx, dy);
}


static void 
XAASpanHelper(ScrnInfoPtr pScrn, int x1, int y, int width)
{
   XAAInfoRecPtr infoRec = GET_XAAINFORECPTR_FROM_SCRNINFOPTR(pScrn);
   BoxPtr extents = infoRec->ClipBox;
    int x2;

    if((y < extents->y1) || (y >= extents->y2)) return;

    x2 = x1 + width;
    if(x1 < extents->x1) x1 = extents->x1;
    if(x2 > extents->x2) x2 = extents->x2;
    width = x2 - x1;	

    if(width > 0)	
 	(*infoRec->SubsequentSolidFillRect)(pScrn, x1, y, width, 1);

}

#define FixError(x, dx, dy, e, sign, step, h)	{	\
	   e += (h) * dx;				\
	   x += (h) * step;				\
	   if(e > 0) {					\
		x += e * sign/dy;			\
		e %= dy;				\
	   	if(e) {					\
		   x += sign;				\
		   e -= dy;				\
		}					\
	   } 	 					\
}


static void
XAAFillPolyHelper (
    GCPtr	pGC,
    int		y,			/* start y coordinate */
    int		overall_height,		/* height of entire segment */
    PolyEdgePtr	left, PolyEdgePtr right,
    int	left_count, int right_count )
{
    XAAInfoRecPtr infoRec = GET_XAAINFORECPTR_FROM_GC(pGC);
    BoxPtr extents = infoRec->ClipBox;
    int left_x, left_e, left_stepx, left_signdx, left_dy, left_dx;
    int right_x, right_e, right_stepx, right_signdx, right_dy, right_dx;
    int	height, left_height, right_height;
    int	xorg;
    Bool hardClip;

    if((y >= extents->y2) || ((y + overall_height) <= extents->y1))
	return;

    /* Muffle compiler */
    left_x = left_e = left_stepx = left_signdx = left_dy = left_dx = 0;
    right_x = right_e = right_stepx = right_signdx = right_dy = right_dx = 0;

    left_height = right_height = 0;
    xorg = 0;

    hardClip = (infoRec->ClippingFlags & HARDWARE_CLIP_SOLID_FILL);
    
    while ((left_count || left_height) && (right_count || right_height)) {
  	if (!left_height && left_count) { 
	    left_height = left->height; 
	    left_x = left->x + xorg; 
	    left_stepx = left->stepx; 
	    left_signdx = left->signdx; 
	    left_e = left->e; 
	    left_dy = left->dy; 
	    left_dx = left->dx; 
	    left_count--; 
	    left++;
	}
	if (!right_height && right_count) { 
	    right_height = right->height; 
	    right_x = right->x + xorg + 1; 
	    right_stepx = right->stepx; 
	    right_signdx = right->signdx; 
	    right_e = right->e; 
	    right_dy = right->dy; 
	    right_dx = right->dx; 
	    right_count--; 
	    right++; 
	}

	height = (left_height > right_height) ? right_height : left_height;

	left_height -= height;
	right_height -= height;

	if(hardClip && infoRec->SubsequentSolidFillTrap && (height > 6)) {
	    int right_DX, left_DX;

    	    right_DX = (right_dx * right_signdx) + (right_stepx * right_dy);
	    left_DX = (left_dx * left_signdx) + (left_stepx * left_dy);

	    (*infoRec->SubsequentSolidFillTrap)(infoRec->pScrn, y, height, 
			left_x, left_DX, left_dy, left_e, 
			right_x - 1, right_DX, right_dy, right_e);

	    FixError(left_x, left_dx, left_dy, left_e, left_signdx, 
			left_stepx, height);
	    FixError(right_x, right_dx, right_dy, right_e, right_signdx,
			right_stepx, height);
	    y += height;
	    continue;
	}

	while (height--) {
	    if(right_x > left_x) {
		FILL_SPAN(infoRec->pScrn, left_x, y, right_x - left_x);
	    }
    	    y++;
    	
 	    left_x += left_stepx; 
	    left_e += left_dx; 
	    if (left_e > 0) { 
		left_x += left_signdx; 
		left_e -= left_dy; 
	    }
	    right_x += right_stepx; 
	    right_e += right_dx; 
	    if (right_e > 0) { 
		right_x += right_signdx; 
		right_e -= right_dy; 
	    }

	}
    }
}



static void
XAAWideSegment (
    GCPtr pGC,
    int  x1, int y1, int x2, int y2,
    Bool projectLeft, Bool projectRight,
    LineFacePtr leftFace, LineFacePtr rightFace )
{
    XAAInfoRecPtr infoRec = GET_XAAINFORECPTR_FROM_GC(pGC);
    double	l, L, r;
    double	xa, ya;
    double	projectXoff, projectYoff;
    double	k;
    double	maxy;
    int		x, y;
    int		dx, dy;
    int		finaly;
    PolyEdgePtr left, right;
    PolyEdgePtr	top, bottom;
    int		lefty, righty, topy, bottomy;
    int		signdx;
    PolyEdgeRec	lefts[2], rights[2];
    LineFacePtr	tface;
    int		lw = pGC->lineWidth;
    Bool	hardClip = (infoRec->ClippingFlags & HARDWARE_CLIP_SOLID_FILL);

    /* draw top-to-bottom always */
    if ((y2 < y1) || ((y2 == y1) && (x2 < x1))) {
	x = x1;
	x1 = x2;
	x2 = x;

	y = y1;
	y1 = y2;
	y2 = y;

	x = projectLeft;
	projectLeft = projectRight;
	projectRight = x;

	tface = leftFace;
	leftFace = rightFace;
	rightFace = tface;
    }

    dy = y2 - y1;
    signdx = 1;
    dx = x2 - x1;
    if (dx < 0)
	signdx = -1;

    leftFace->x = x1;
    leftFace->y = y1;
    leftFace->dx = dx;
    leftFace->dy = dy;

    rightFace->x = x2;
    rightFace->y = y2;
    rightFace->dx = -dx;
    rightFace->dy = -dy;

    if (!dy) {
	rightFace->xa = 0;
	rightFace->ya = (double) lw / 2.0;
	rightFace->k = -(double) (lw * dx) / 2.0;
	leftFace->xa = 0;
	leftFace->ya = -rightFace->ya;
	leftFace->k = rightFace->k;
	x = x1;
	if (projectLeft)
	    x -= (lw >> 1);
	y = y1 - (lw >> 1);
	dx = x2 - x;
	if (projectRight)
	    dx += ((lw + 1) >> 1);
	dy = lw;
	FILL_RECT(infoRec->pScrn, x, y, dx, dy);	
    } else if (!dx) {
	leftFace->xa =  (double) lw / 2.0;
	leftFace->ya = 0;
	leftFace->k = (double) (lw * dy) / 2.0;
	rightFace->xa = -leftFace->xa;
	rightFace->ya = 0;
	rightFace->k = leftFace->k;
	y = y1;
	if (projectLeft)
	    y -= lw >> 1;
	x = x1 - (lw >> 1);
	dy = y2 - y;
	if (projectRight)
	    dy += ((lw + 1) >> 1);
	dx = lw;
 	FILL_RECT(infoRec->pScrn, x, y, dx, dy);
    } else {
    	l = ((double) lw) / 2.0;
    	L = sqrt((double)(dx*dx + dy*dy));

	if (dx < 0) {
	    right = &rights[1];
	    left = &lefts[0];
	    top = &rights[0];
	    bottom = &lefts[1];
	} else {
	    right = &rights[0];
	    left = &lefts[1];
	    top = &lefts[0];
	    bottom = &rights[1];
	}
	r = l / L;

	/* coord of upper bound at integral y */
	ya = -r * dx;
	xa = r * dy;

	projectXoff = -ya;
	projectYoff = xa;

    	/* xa * dy - ya * dx */
	k = l * L;

	leftFace->xa = xa;
	leftFace->ya = ya;
	leftFace->k = k;
	rightFace->xa = -xa;
	rightFace->ya = -ya;
	rightFace->k = k;

	if (projectLeft)
	    righty = miPolyBuildEdge (xa - projectXoff, ya - projectYoff,
				      k, dx, dy, x1, y1, 0, right);
	else
	    righty = miPolyBuildEdge (xa, ya,
				      k, dx, dy, x1, y1, 0, right);

	/* coord of lower bound at integral y */
	ya = -ya;
	xa = -xa;

	/* xa * dy - ya * dx */
	k = - k;

	if (projectLeft)
	    lefty = miPolyBuildEdge (xa - projectXoff, ya - projectYoff,
				     k, dx, dy, x1, y1, 1, left);
	else
	    lefty = miPolyBuildEdge (xa, ya,
				     k, dx, dy, x1, y1, 1, left);

	/* coord of top face at integral y */

	if (signdx > 0) {
	    ya = -ya;
	    xa = -xa;
	}

	if (projectLeft) {
	    double xap = xa - projectXoff;
	    double yap = ya - projectYoff;
	    topy = miPolyBuildEdge (xap, yap, xap * dx + yap * dy,
				    -dy, dx, x1, y1, dx > 0, top);
	}
	else
	    topy = miPolyBuildEdge(xa, ya, 0.0, 
					-dy, dx, x1, y1, dx > 0, top);

		/* coord of bottom face at integral y */

	if (projectRight) {
	    double xap = xa + projectXoff;
	    double yap = ya + projectYoff;
	    bottomy = miPolyBuildEdge (xap, yap, xap * dx + yap * dy,
				       -dy, dx, x2, y2, dx < 0, bottom);
	    maxy = -ya + projectYoff;
	} else {
	    bottomy = miPolyBuildEdge (xa, ya, 0.0,
					-dy, dx, x2, y2, dx < 0, bottom);
	    maxy = -ya;
	}

	finaly = ICEIL (maxy) + y2;

	if (dx < 0) {
	    left->height = bottomy - lefty;
	    right->height = finaly - righty;
	    top->height = righty - topy;
	} else {
	    right->height =  bottomy - righty;
	    left->height = finaly - lefty;
	    top->height = lefty - topy;
	}
	bottom->height = finaly - bottomy;
	XAAFillPolyHelper (pGC, topy, 
		bottom->height + bottomy - topy, lefts, rights, 2, 2);
    }
}


static void
XAALineArcI (GCPtr pGC, int xorg, int yorg)
{
    XAAInfoRecPtr infoRec = GET_XAAINFORECPTR_FROM_GC(pGC);
    int x, y, e, ex;
    int slw = pGC->lineWidth;
    Bool hardClip = (infoRec->ClippingFlags & HARDWARE_CLIP_SOLID_FILL);

    y = (slw >> 1) + 1;
    if (slw & 1)
	e = - ((y << 2) + 3);
    else
	e = - (y << 3);
    ex = -4;
    x = 0;
    while (y) {
	e += (y << 3) - 4;
	while (e >= 0) {
	    x++;
	    e += (ex = -((x << 3) + 4));
	}
	y--;
	slw = (x << 1) + 1;
	if ((e == ex) && (slw > 1))
	    slw--;
	    
	FILL_SPAN(infoRec->pScrn, xorg - x, yorg - y, slw);

	if ((y != 0) && ((slw > 1) || (e != ex))) {	
	    FILL_SPAN(infoRec->pScrn, xorg - x, yorg + y, slw);
	}
    }
}


static void
XAALineArcD (
    GCPtr	    pGC,
    double	    xorg,
    double	    yorg,
    PolyEdgePtr	    edge1, 
    int		    edgey1,
    Bool	    edgeleft1,
    PolyEdgePtr	    edge2,
    int		    edgey2,
    Bool	    edgeleft2 )
{
    XAAInfoRecPtr infoRec = GET_XAAINFORECPTR_FROM_GC(pGC);
    double radius, x0, y0, el, er, yk, xlk, xrk, k;
    int xbase, ybase, y, boty, xl, xr, xcl, xcr;
    int ymin, ymax;
    Bool edge1IsMin, edge2IsMin;
    int ymin1, ymin2;
    Bool hardClip = (infoRec->ClippingFlags & HARDWARE_CLIP_SOLID_FILL);


    xbase = floor(xorg);
    x0 = xorg - xbase;
    ybase = ICEIL (yorg);
    y0 = yorg - ybase;

    xlk = x0 + x0 + 1.0;
    xrk = x0 + x0 - 1.0;
    yk = y0 + y0 - 1.0;
    radius = ((double)pGC->lineWidth) / 2.0;
    y = floor(radius - y0 + 1.0);
    ybase -= y;
    ymin = ybase;
    ymax = 65536;
    edge1IsMin = FALSE;
    ymin1 = edgey1;
    if (edge1->dy >= 0) {
    	if (!edge1->dy) {
	    if (edgeleft1)
	    	edge1IsMin = TRUE;
	    else
	    	ymax = edgey1;
	    edgey1 = 65536;
    	} else if ((edge1->signdx < 0) == edgeleft1)
	    	edge1IsMin = TRUE;
    }
    edge2IsMin = FALSE;
    ymin2 = edgey2;
    if (edge2->dy >= 0) {
    	if (!edge2->dy) {
	    if (edgeleft2)
	    	edge2IsMin = TRUE;
	    else
	    	ymax = edgey2;
	    edgey2 = 65536;
    	} else if ((edge2->signdx < 0) == edgeleft2)
	    	edge2IsMin = TRUE;
    }
    if (edge1IsMin) {
	ymin = ymin1;
	if (edge2IsMin && (ymin1 > ymin2))
	    ymin = ymin2;
    } else if (edge2IsMin)
	ymin = ymin2;
    el = radius * radius - ((y + y0) * (y + y0)) - (x0 * x0);
    er = el + xrk;
    xl = 1;
    xr = 0;
    if (x0 < 0.5) {
	xl = 0;
	el -= xlk;
    }
    boty = (y0 < -0.5) ? 1 : 0;
    if (ybase + y - boty > ymax)
	boty = ymax - ybase - y;
    while (y > boty) {
	k = (y << 1) + yk;
	er += k;
	while (er > 0.0) {
	    xr++;
	    er += xrk - (xr << 1);
	}
	el += k;
	while (el >= 0.0) {
	    xl--;
	    el += (xl << 1) - xlk;
	}
	y--;
	ybase++;
	if (ybase < ymin)
	    continue;
	xcl = xl + xbase;
	xcr = xr + xbase;
	CLIPSTEPEDGE(edgey1, edge1, edgeleft1);
	CLIPSTEPEDGE(edgey2, edge2, edgeleft2);
	if(xcr >= xcl) {
	    FILL_SPAN(infoRec->pScrn, xcl, ybase, xcr - xcl + 1);
	}
    }
    er = xrk - (xr << 1) - er;
    el = (xl << 1) - xlk - el;
    boty = floor(-y0 - radius + 1.0);
    if (ybase + y - boty > ymax)
	boty = ymax - ybase - y;
    while (y > boty) {
	k = (y << 1) + yk;
	er -= k;
	while ((er >= 0.0) && (xr >= 0)) {
	    xr--;
	    er += xrk - (xr << 1);
	}
	el -= k;
	while ((el > 0.0) && (xl <= 0)) {
	    xl++;
	    el += (xl << 1) - xlk;
	}
	y--;
	ybase++;
	if (ybase < ymin)
	    continue;
	xcl = xl + xbase;
	xcr = xr + xbase;
	CLIPSTEPEDGE(edgey1, edge1, edgeleft1);
	CLIPSTEPEDGE(edgey2, edge2, edgeleft2);
	if(xcr >= xcl) {
	    FILL_SPAN(infoRec->pScrn, xcl, ybase, xcr - xcl + 1);
	}
    }
}


static void
XAALineArc (
    GCPtr  pGC,
    LineFacePtr leftFace,
    LineFacePtr rightFace,
    double	xorg,
    double	yorg,
    Bool	isInt )
{
    int xorgi, yorgi;
    PolyEdgeRec	edge1, edge2;
    int		edgey1, edgey2;
    Bool	edgeleft1, edgeleft2;

    if (isInt) {
	xorgi = leftFace ? leftFace->x : rightFace->x;
	yorgi = leftFace ? leftFace->y : rightFace->y;
    } else {	/* Muffle compiler */
        xorgi = yorgi = 0;
    }
    edgey1 = 65536;
    edgey2 = 65536;
    edge1.x = 0; /* not used, keep memory checkers happy */
    edge1.dy = -1;
    edge2.x = 0; /* not used, keep memory checkers happy */
    edge2.dy = -1;
    edgeleft1 = FALSE;
    edgeleft2 = FALSE;

    if ((pGC->lineWidth > 2) &&
	((pGC->capStyle == CapRound && pGC->joinStyle != JoinRound) ||
	 (pGC->joinStyle == JoinRound && pGC->capStyle == CapButt))) {
	if (isInt) {
	    xorg = (double) xorgi;
	    yorg = (double) yorgi;
	}

	if (leftFace && rightFace) 
	    miRoundJoinClip (leftFace, rightFace, &edge1, &edge2,
			     &edgey1, &edgey2, &edgeleft1, &edgeleft2);
	else if (leftFace)
	    edgey1 = miRoundCapClip (leftFace, isInt, &edge1, &edgeleft1);
	else if (rightFace)
	    edgey2 = miRoundCapClip (rightFace, isInt, &edge2, &edgeleft2);

	isInt = FALSE;
    }

    if (isInt) {
	if(pGC->lineWidth == 1) {
	    XAAInfoRecPtr infoRec = GET_XAAINFORECPTR_FROM_GC(pGC);
	    Bool hardClip = (infoRec->ClippingFlags & HARDWARE_CLIP_SOLID_FILL);
	    DRAW_POINT(infoRec->pScrn, xorgi, yorgi);
	} else
	    XAALineArcI(pGC, xorgi, yorgi);
    } else
	XAALineArcD(pGC, xorg, yorg, &edge1, edgey1, edgeleft1,
		       &edge2, edgey2, edgeleft2);

}


static void
XAALineJoin (
    GCPtr	    pGC,
    LineFacePtr     pLeft,
    LineFacePtr     pRight )
{
    double	    mx = 0, my = 0;
    double	    denom = 0;
    PolyVertexRec   vertices[4];
    PolySlopeRec    slopes[4];
    int		    edgecount;
    PolyEdgeRec	    left[4], right[4];
    int		    nleft, nright;
    int		    y, height;
    int		    swapslopes;
    int		    joinStyle = pGC->joinStyle;
    int		    lw = pGC->lineWidth;

    if (lw == 1) {
	/* Lines going in the same direction have no join */
	if ((pLeft->dx >= 0) == (pRight->dx <= 0))
	    return;
	if (joinStyle != JoinRound) {
    	    denom = - pLeft->dx * (double)pRight->dy + pRight->dx *
 					(double)pLeft->dy;
    	    if (denom == 0.0)
	    	return;	/* no join to draw */
	}
	if (joinStyle != JoinMiter) {
	    XAAInfoRecPtr infoRec = GET_XAAINFORECPTR_FROM_GC(pGC);
	    Bool hardClip = (infoRec->ClippingFlags & HARDWARE_CLIP_SOLID_FILL);
	    DRAW_POINT(infoRec->pScrn, pLeft->x, pLeft->y);	
	    return;
	}
    } else {
    	if (joinStyle == JoinRound) {
	    XAALineArc(pGC, pLeft, pRight,(double)0.0, (double)0.0, TRUE);
	    return;
    	}
    	denom = - pLeft->dx * (double)pRight->dy + pRight->dx * 
				(double)pLeft->dy;
    	if (denom == 0.0)
	    return;	/* no join to draw */
    }

    swapslopes = 0;
    if (denom > 0) {
	pLeft->xa = -pLeft->xa;
	pLeft->ya = -pLeft->ya;
	pLeft->dx = -pLeft->dx;
	pLeft->dy = -pLeft->dy;
    } else {
	swapslopes = 1;
	pRight->xa = -pRight->xa;
	pRight->ya = -pRight->ya;
	pRight->dx = -pRight->dx;
	pRight->dy = -pRight->dy;
    }

    vertices[0].x = pRight->xa;
    vertices[0].y = pRight->ya;
    slopes[0].dx = -pRight->dy;
    slopes[0].dy =  pRight->dx;
    slopes[0].k = 0;

    vertices[1].x = 0;
    vertices[1].y = 0;
    slopes[1].dx =  pLeft->dy;
    slopes[1].dy = -pLeft->dx;
    slopes[1].k = 0;

    vertices[2].x = pLeft->xa;
    vertices[2].y = pLeft->ya;

    if (joinStyle == JoinMiter) {
    	my = (pLeft->dy  * (pRight->xa * pRight->dy - pRight->ya * pRight->dx) -
              pRight->dy * (pLeft->xa  * pLeft->dy  - pLeft->ya  * pLeft->dx ))/
	      denom;
    	if (pLeft->dy != 0) 
	    mx = pLeft->xa + (my - pLeft->ya) *
			    (double) pLeft->dx / (double) pLeft->dy;
    	else
	    mx = pRight->xa + (my - pRight->ya) *
			    (double) pRight->dx / (double) pRight->dy;
    	
	/* check miter limit */
	if ((mx * mx + my * my) * 4 > SQSECANT * lw * lw)
	    joinStyle = JoinBevel;
    }

    if (joinStyle == JoinMiter) {
	slopes[2].dx = pLeft->dx;
	slopes[2].dy = pLeft->dy;
	slopes[2].k =  pLeft->k;
	if (swapslopes) {
	    slopes[2].dx = -slopes[2].dx;
	    slopes[2].dy = -slopes[2].dy;
	    slopes[2].k  = -slopes[2].k;
	}
	vertices[3].x = mx;
	vertices[3].y = my;
	slopes[3].dx = pRight->dx;
	slopes[3].dy = pRight->dy;
	slopes[3].k  = pRight->k;
	if (swapslopes) {
	    slopes[3].dx = -slopes[3].dx;
	    slopes[3].dy = -slopes[3].dy;
	    slopes[3].k  = -slopes[3].k;
	}
	edgecount = 4;
    } else {
	double	scale, dx, dy, adx, ady;

	adx = dx = pRight->xa - pLeft->xa;
	ady = dy = pRight->ya - pLeft->ya;
	if (adx < 0)
	    adx = -adx;
	if (ady < 0)
	    ady = -ady;
	scale = ady;
	if (adx > ady)
	    scale = adx;
	slopes[2].dx = (dx * 65536) / scale;
	slopes[2].dy = (dy * 65536) / scale;
	slopes[2].k = ((pLeft->xa + pRight->xa) * slopes[2].dy -
		       (pLeft->ya + pRight->ya) * slopes[2].dx) / 2.0;
	edgecount = 3;
    }

    y = miPolyBuildPoly (vertices, slopes, edgecount, pLeft->x, pLeft->y,
		   left, right, &nleft, &nright, &height);
    XAAFillPolyHelper(pGC, y, height, left, right, nleft, nright);
}


void
XAAPolylinesWideSolid (
   DrawablePtr  pDrawable,
   GCPtr        pGC,
   int          mode,
   int          npt,
   DDXPointPtr  pPts )
{
    XAAInfoRecPtr infoRec = GET_XAAINFORECPTR_FROM_GC(pGC);
    int		    x1, y1, x2, y2;
    Bool	    projectLeft, projectRight;
    LineFaceRec	    leftFace, rightFace, prevRightFace, firstFace;
    int    	    first = TRUE;
    Bool	    somethingDrawn = FALSE;
    Bool	    selfJoin = FALSE;
    int		    xorg = pDrawable->x;
    int		    yorg = pDrawable->y;
    Bool	    hardClip = FALSE;

    if(!REGION_NUM_RECTS(pGC->pCompositeClip))
	return;

    if(REGION_NUM_RECTS(pGC->pCompositeClip) != 1) {
	miWideLine(pDrawable, pGC, mode, npt, pPts);
	return;
    }

    x2 = pPts->x;
    y2 = pPts->y;
    if (npt > 1) {
    	if (mode == CoordModePrevious) {
	    int nptTmp;
	    register DDXPointPtr pPtsTmp;
    
	    x1 = x2;
	    y1 = y2;
	    nptTmp = npt;
	    pPtsTmp = pPts + 1;
	    while (--nptTmp) {
	    	x1 += pPtsTmp->x;
	    	y1 += pPtsTmp->y;
	    	++pPtsTmp;
	    }
	    if ((x2 == x1) && (y2 == y1))
	    	selfJoin = TRUE;
    	} else if ((x2 == pPts[npt-1].x) && (y2 == pPts[npt-1].y)) 
	    selfJoin = TRUE;
    }

    projectLeft = ((pGC->capStyle == CapProjecting) && !selfJoin);
    projectRight = FALSE;

    (*infoRec->SetupForSolidFill)(infoRec->pScrn, pGC->fgPixel, pGC->alu, 
						pGC->planemask);

    infoRec->ClipBox = &pGC->pCompositeClip->extents;

    if(infoRec->ClippingFlags & HARDWARE_CLIP_SOLID_FILL) {
	hardClip = TRUE;
	(*infoRec->SetClippingRectangle)(infoRec->pScrn,
              infoRec->ClipBox->x1, infoRec->ClipBox->y1, 
              infoRec->ClipBox->x2 - 1, infoRec->ClipBox->y2 - 1);		
    }

    x2 += xorg;
    y2 += yorg;
    while (--npt) {
	x1 = x2;
	y1 = y2;
	++pPts;
	x2 = pPts->x;
	y2 = pPts->y;
	if (mode == CoordModePrevious) {
	    x2 += x1;
	    y2 += y1;
	} else {
	    x2 += xorg;
	    y2 += yorg;
	}
	if ((x1 != x2) || (y1 != y2)) {
	    somethingDrawn = TRUE;
	    if ((npt == 1) && (pGC->capStyle == CapProjecting) && !selfJoin)
	    	projectRight = TRUE;
	    XAAWideSegment(pGC, x1, y1, x2, y2,
		       	   projectLeft, projectRight, &leftFace, &rightFace);
	    if (first) {
	    	if (selfJoin)
		    firstFace = leftFace;
	    	else if (pGC->capStyle == CapRound) {
		    if (pGC->lineWidth == 1) {
			DRAW_POINT(infoRec->pScrn, x1, y1);
		    } else
		        XAALineArc(pGC,&leftFace, (LineFacePtr) NULL,
 			       	   (double)0.0, (double)0.0,TRUE);
		}
	    } else 
	    	XAALineJoin (pGC, &leftFace, &prevRightFace);

	    prevRightFace = rightFace;
	    first = FALSE;
	    projectLeft = FALSE;
	}
	if (npt == 1 && somethingDrawn) {
	    if (selfJoin)
		XAALineJoin (pGC, &firstFace, &rightFace);
	    else if (pGC->capStyle == CapRound) {
		if (pGC->lineWidth == 1) {
		    DRAW_POINT(infoRec->pScrn, x2, y2);
		} else
		    XAALineArc (pGC, (LineFacePtr) NULL, &rightFace,
			       (double)0.0, (double)0.0,TRUE);
	    }
	}
    }
    /* handle crock where all points are coincedent */
    if (!somethingDrawn) {
	projectLeft = (pGC->capStyle == CapProjecting);
	XAAWideSegment (pGC, x2, y2, x2, y2, projectLeft, projectLeft,
		       &leftFace, &rightFace);
	if (pGC->capStyle == CapRound) {
	    XAALineArc (pGC, &leftFace, (LineFacePtr) NULL,
		       (double)0.0, (double)0.0, TRUE);
	    rightFace.dx = -1;	/* sleezy hack to make it work */
	    XAALineArc (pGC, (LineFacePtr) NULL, &rightFace,
 		       (double)0.0, (double)0.0, TRUE);
	}
   }

   infoRec->ClipBox = NULL;
   if(hardClip)
	(*infoRec->DisableClipping)(infoRec->pScrn);

   SET_SYNC_FLAG(infoRec);
}

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