--- ray/src/hd/rhd_odraw.c	1998/12/21 13:17:00	3.3
+++ ray/src/hd/rhd_odraw.c	1998/12/23 17:42:24	3.6
@@ -14,7 +14,6 @@ static char SCCSid[] = "$SunId$ SGI";
 #include <GL/glx.h>
 #include <GL/glu.h>
 
-#include "random.h"
 #include "rhd_odraw.h"
 
 #ifndef DEPTHEPS
@@ -131,6 +130,7 @@ int	n;
 		DCHECK(count<=0 | nextsamp>=n,
 				CONSISTENCY, "counter botch in odInit");
 		if (!i) count = j;
+		odView[i].sfirst = nextsamp;
 		while (j--) {		/* initialize blocks & free lists */
 			odView[i].bmap[j].pthresh = FHUGE;
 			odView[i].bmap[j].first = k = nextsamp;
@@ -142,6 +142,7 @@ int	n;
 			odS.nextfree(k-1) = ENDFREE;
 			odView[i].bmap[j].nused = 0;
 		}
+		odView[i].snext = nextsamp;
 	}
 	CLR4ALL(odS.redraw, odS.nsamp);		/* clear redraw flags */
 	for (i = odS.nsamp; i--; ) {		/* clear values */
@@ -316,6 +317,18 @@ int	newhist;
 }
 
 
+odRedrawAll()				/* mark all samples for redraw */
+{
+	register int	i;
+
+	if ((needmapping&(NEWMAP|NEWRGB)) == (NEWMAP|NEWRGB))
+		return;			/* will be called later, anyway */
+	for (i = odS.nsamp; i--; )
+		if (odS.ip[i][0] >= 0)
+			SET4(odS.redraw, i);
+}
+
+
 odRedraw(vn, hmin, vmin, hmax, vmax)	/* redraw view region */
 int	vn, hmin, vmin, hmax, vmax;
 {
@@ -424,9 +437,7 @@ GLfloat	*dm;
 odUpdate(vn)				/* update this view */
 int	vn;
 {
-	int	i, j;
-	register struct ODblock	*bp;
-	register int	k;
+	register int	i, j;
 
 	DCHECK(vn<0 | vn>=odNViews, CONSISTENCY,
 			"bad view number in odUpdate");
@@ -435,39 +446,49 @@ int	vn;
 		if (needmapping & NEWMAP) {
 			if (needmapping & NEWHIST)
 				tmClearHisto();
+			needmapping &= ~NEWHIST;
 			if (tmAddHisto(odS.brt,odS.nsamp,1) != TM_E_OK)
 				return;
 			if (tmComputeMapping(0.,0.,0.) != TM_E_OK)
 				return;
-			for (k = odS.nsamp; k--; )	/* redraw all */
-				if (odS.ip[k][0] >= 0)
-					SET4(odS.redraw, k);
+			needmapping &= ~NEWMAP;
+			odRedrawAll();			/* redraw everything */
 		}
 		if (tmMapPixels(odS.rgb,odS.brt,odS.chr,odS.nsamp) != TM_E_OK)
 			return;
-		needmapping = 0;		/* reset flag */
+		needmapping &= ~NEWRGB;
 	}
-					/* draw each block in view */
-	for (j = odView[vn].vlow; j--; )
-		for (i = 0; i < odView[vn].hlow; i++) {
-					/* get block */
-			bp = odView[vn].bmap + j*odView[vn].hlow + i;
-					/* do quick, conservative flag check */
-			for (k = (bp->first+bp->nsamp+31)>>5;
-					k-- > bp->first>>5; )
-				if (odS.redraw[k])
-					break;		/* non-zero flag */
-			if (k < bp->first>>5)
-				continue;		/* no flags set */
-			for (k = bp->nsamp; k--; )	/* sample by sample */
-				if (CHK4(odS.redraw, bp->first+k)) {
-					odDrawBlockSamp(vn, i, j, bp->first+k);
-					CLR4(odS.redraw, bp->first+k);
-				}
+					/* this code segment was too slow */
+#if 0
+	for (i = odView[vn].sfirst; i < odView[vn].snext; i++)
+		if (CHK4(odS.redraw, i)) {
+			odDrawSamp(vn, i);
+			CLR4(odS.redraw, i);
 		}
+#else
+					/* redraw samples at each end */
+	for (i = odView[vn].sfirst; i < odView[vn].sfirst+31; i++)
+		if (CHK4(odS.redraw, i)) {
+			odDrawSamp(vn, i);
+			CLR4(odS.redraw, i);
+		}
+	for (i = odView[vn].snext-31; i < odView[vn].snext; i++)
+		if (CHK4(odS.redraw, i)) {
+			odDrawSamp(vn, i);
+			CLR4(odS.redraw, i);
+		}
+					/* faster flag checks in middle */
+	for (j = odView[vn].snext>>5; j-- > (odView[vn].sfirst+0x1f)>>5; )
+		for (i = 0; odS.redraw[j]; i++)		/* skips faster */
+			if (odS.redraw[j] & 1L<<i) {
+				odDrawSamp(vn, (j<<5)+i);
+				odS.redraw[j] &= ~(1L<<i);
+			}
+#endif
 }
 
 
+					/* this turned out to be unnecessary */
 #if 0
 static
 clip_end(p, o, vp)			/* clip line segment to view */
@@ -505,7 +526,7 @@ register struct ODview	*vp;
 double	sz;
 {
 	int	na, dv;
-	double	hrad, vrad, phi0, phi;
+	double	hrad, vrad, phi;
 	register int	i;
 
 	DCHECK(sz > 1, CONSISTENCY, "super-unary size in make_arms");
@@ -515,10 +536,9 @@ double	sz;
 	vrad = FANSIZE*sz*vp->vhi/vp->vlow;
 	if (hrad*vrad < 2.25)
 		hrad = vrad = 1.5;
-	phi0 = (2.*PI) * frandom();
 	dv = OMAXDEPTH*sz + 0.5;
 	for (i = 0; i < na; i++) {
-		phi = phi0 + (2.*PI)*i/na;
+		phi = (2.*PI)*i/na;
 		ar[i][0] = cp[0] + tcos(phi)*hrad + 0.5;
 		ar[i][1] = cp[1] + tsin(phi)*vrad + 0.5;
 		ar[i][2] = dv;
@@ -603,36 +623,46 @@ register int	h, v;
 }
 
 
-odDrawBlockSamp(vn, h, v, id)		/* draw sample in view block */
-int	vn, h, v;
+static int
+blockedge(vp, bi0, bi1)			/* check for edge between blocks? */
+register struct ODview	*vp;
+register int	bi0, bi1;
+{
+	if (bi1 < 0)
+		return(1);		/* end off view */
+	if (CHK4(vp->emap, bi1))
+		return(1);		/* end has edges */
+	if (bi1 == bi0+1 || bi1 == bi0-1 ||
+			bi1 == bi0+vp->hlow || bi1 == bi0-vp->hlow)
+		return(0);		/* end in adjacent block -- no edges */
+	return(1);			/* conservative for rarer case */
+}
+
+
+odDrawSamp(vn, id)			/* draw view sample */
+int	vn;
 register int	id;
 {
 	GLshort	arm[MAXFAN][3];
-	int	narms, blockindex, bi1;
+	int	narms, blockindex;
 	register struct ODview	*vp;
 	double	size;
 	int	home_edges;
 	register int	i;
 
 	vp = odView + vn;
-	blockindex = v*vp->hlow + h;
-	DCHECK(odS.ip[id][0]*vp->hlow/vp->hhi != h |
-			odS.ip[id][1]*vp->vlow/vp->vhi != v,
-			CONSISTENCY, "bad sample position in odDrawBlockSamp");
+	blockindex = getblock(vp, odS.ip[id][0], odS.ip[id][1]);
+	DCHECK(blockindex<0, CONSISTENCY, "bad sample handed to odDrawSamp");
 	DCHECK(vp->bmap[blockindex].nused <= 0,
-			CONSISTENCY, "bad in-use count in odDrawBlockSamp");
+			CONSISTENCY, "bad in-use count in odDrawSamp");
 					/* create triangle fan */
 	size = 1./sqrt((double)vp->bmap[blockindex].nused);
 	narms = make_arms(arm, odS.ip[id], vp, size);
 	if (vp->emap != NULL) {		/* check for edge collisions */
 		home_edges = CHK4(vp->emap, blockindex);
 		for (i = 0; i < narms; i++)
-			/* the following test is flawed, because we could
-			 * be passing through a block on a diagonal run */
-			if (home_edges ||
-				( (bi1 = getblock(vp, arm[i][0], arm[i][1]))
-						!= blockindex &&
-					(bi1 < 0 || CHK4(vp->emap, bi1)) ))
+			if (home_edges || blockedge(vp, blockindex,
+					getblock(vp, arm[i][0], arm[i][1])))
 				clip_edge(arm[i], odS.ip[id], vp);
 	}
 					/* draw triangle fan */