diff -r 558fde7da82a -r 14a727b70d07 src/sampler.cc
--- a/src/sampler.cc	Fri Mar 28 00:53:20 2008 +0100
+++ b/src/sampler.cc	Fri Mar 28 17:13:21 2008 +0100
@@ -42,6 +42,7 @@
 	{
 		cout << "phase 1" << endl;
 		phase++;
+		sx = -1;
 		return w*h*samples;
 	}
 	else if ( phase == 1 && oversample )
@@ -60,7 +61,7 @@
 	}
 }
 
-Sample* DefaultSampler::nextSample(Sample *prev)
+Sample* DefaultSampler::nextSample()
 {
 	DefaultSample *s = new DefaultSample;
 
@@ -84,58 +85,56 @@
 	const Float *osax = osaSx[oversample];
 	const Float *osay = osaSy[oversample];
 
-	if (!prev)
+	if (sx < 0)
 	{
 		// first sample
 		s->x = -(Float)w/h/2.0;
 		s->y = -0.5;
-		s->sx = 0;
-		s->sy = 0;
-		s->osa_samp = 0;
+		sx = 0;
+		sy = 0;
+		osa_samp = 0;
 	}
 	else
 	{
-		DefaultSample *sp = static_cast<DefaultSample*>(prev);
-
-		s->osa_samp = sp->osa_samp + 1;
+		osa_samp++;
 
-		if (oversample && oversample <= 3 && s->osa_samp < samples)
+		if (oversample && oversample <= 3 && osa_samp < samples)
 		{
-			s->sx = sp->sx;
-			s->sy = sp->sy;
-			s->x = osax[s->osa_samp]/h + (Float)s->sx/h - (Float)w/h/2.0;
-			s->y = osay[s->osa_samp]/h + (Float)s->sy/h - 0.5;
+			s->x = osax[osa_samp]/h + (Float)sx/h - (Float)w/h/2.0;
+			s->y = osay[osa_samp]/h + (Float)sy/h - 0.5;
 		}
 		else
 		{
-			s->sx = sp->sx + 1;
-			s->sy = sp->sy;
-			if (s->sx >= w)
+			sx++;
+			if (sx >= w)
 			{
-				s->sx = 0;
-				s->sy++;
+				sx = 0;
+				sy++;
 			}
-			if (s->sy >= h)
+			if (sy >= h)
 			{
 				delete s;
 				return NULL;
 			}
-			s->x = (Float)s->sx/h - (Float)w/h/2.0;
-			s->y = (Float)s->sy/h - 0.5;
-			s->osa_samp = 0;
+			s->x = (Float)sx/h - (Float)w/h/2.0;
+			s->y = (Float)sy/h - 0.5;
+			osa_samp = 0;
 		}
 	}
 
-	if (s->osa_samp == 0 && oversample && oversample <= 3)
+	if (osa_samp == 0 && oversample && oversample <= 3)
 	{
 		s->x += osax[0]/h;
 		s->y += osay[0]/h;
-		Float *buf = buffer + 3*(s->sy*w + s->sx);
+		Float *buf = buffer + 3*(sy*w + sx);
 		*(buf++) = 0;
 		*(buf++) = 0;
 		*(buf++) = 0;
 	}
 
+	s->sx = sx;
+	s->sy = sy;
+	s->osa_samp = osa_samp;
 	return s;
 }