refactor: moved depth-of-field sampling to separate module

src/common/CMakeLists.txt

@@ -52,6 +52,7 @@ set(rtrad_SOURCES
   instance.c
   interp2d.c
   invmat4.c
+  jitteraperture.c
   lamps.c
   linregr.c
   loadbsdf.c

src/common/Rmakefile

@@ -1,4 +1,4 @@
-# RCSid: $Id: Rmakefile,v 2.88 2021/11/19 22:51:31 greg Exp $
+# RCSid: $Id: Rmakefile,v 2.89 2021/12/03 18:10:48 greg Exp $
 #
 # Makefile for ray tracing library routines
 #
@@ -21,7 +21,7 @@ RTOBJ = cone.o face.o free_os.o instance.o readobj.o readoct.o otypes.o \
 PICOBJ = color.o header.o image.o lamps.o resolu.o rexpr.o spec_rgb.o \
 	colrops.o font.o tonemap.o tmapcolrs.o tmapluv.o tmaptiff.o \
 	tmap16bit.o bmpfile.o falsecolor.o depthcodec.o normcodec.o \
-	idmap.o fltdepth.o
+	idmap.o fltdepth.o jitteraperture.o
 
 UTLOBJ = ezxml.o ccolor.o ccyrgb.o bsdf.o bsdf_m.o bsdf_t.o loadbsdf.o \
 	disk2square.o hilbert.o interp2d.o triangulate.o
@@ -124,12 +124,14 @@ readobj.o readoct.o sceneio.o:	otypes.h
 
 multisamp.o urand.o:	random.h
 
-cone.o face.o free_os.o image.o instance.o objset.o \
+cone.o face.o free_os.o instance.o objset.o \
 octree.o modobject.o readfargs.o otypes.o mesh.o \
 readmesh.o readobj.o readoct.o sceneio.o:	standard.h \
 rtmisc.h rtio.h rtmath.h rterror.h fvect.h mat4.h tiff.h
 
-image.o:	view.h
+image.o:	view.h rtio.h rtmath.h mat4.h fvect.h rtio.h paths.h
+
+jitteraperture.o:	view.h rtmath.h mat4.h fvect.h rtio.h
 
 caldefn.o calexpr.o calfunc.o calprnt.o:	calcomp.h
 

src/common/jitteraperture.c

@@ -0,0 +1,63 @@
+#ifndef lint
+static const char	RCSid[] = "$Id: jitteraperture.c,v 2.1 2021/12/03 18:10:48 greg Exp $";
+#endif
+/*
+ *  jitteraperture.c - routine to sample depth-of-field
+ *
+ *  External symbols declared in view.h
+ */
+
+#include "copyright.h"
+
+#include  <stdio.h>
+#include  "rtmath.h"
+#include  "random.h"
+#include  "view.h"
+
+
+int
+jitteraperture(			/* random aperture shift for depth-of-field */
+FVECT  orig,		/* assigned previously by... */
+FVECT  direc,		/* ...viewray() call */
+VIEW  *v,
+double  dia
+)
+{
+	double  vc, df[2];
+	int  i;
+					/* are we even needed? */
+	if (dia <= FTINY)
+		return(1);
+					/* get random point on disk */
+	SDsquare2disk(df, frandom(), frandom());
+	df[0] *= .5*dia;
+	df[1] *= .5*dia;
+	if ((v->type == VT_PER) | (v->type == VT_PAR)) {
+		double	adj = 1.0;	/* basic view cases */
+		if (v->type == VT_PER)
+			adj /= DOT(direc, v->vdir);
+		df[0] /= sqrt(v->hn2);
+		df[1] /= sqrt(v->vn2);
+		for (i = 3; i--; ) {
+			vc = v->vp[i] + adj*v->vdist*direc[i];
+			orig[i] += df[0]*v->hvec[i] +
+						df[1]*v->vvec[i] ;
+			direc[i] = vc - orig[i];
+		}
+	} else {			/* difficult view cases */
+		double	dfd = PI/4.*dia*(.5 - frandom());
+		if ((v->type != VT_ANG) & (v->type != VT_PLS)) {
+			if (v->type != VT_CYL)
+				df[0] /= sqrt(v->hn2);
+			df[1] /= sqrt(v->vn2);
+		}
+		for (i = 3; i--; ) {
+			vc = v->vp[i] + v->vdist*direc[i];
+			orig[i] += df[0]*v->hvec[i] +
+						df[1]*v->vvec[i] +
+						dfd*v->vdir[i] ;
+			direc[i] = vc - orig[i];
+		}
+	}
+	return(normalize(direc) != 0.0);
+}

src/common/view.h

@@ -1,4 +1,4 @@
-/* RCSid $Id: view.h,v 2.20 2018/04/27 05:00:29 greg Exp $ */
+/* RCSid $Id: view.h,v 2.21 2021/12/03 18:10:48 greg Exp $ */
 /*
  *  view.h - header file for image generation.
  *
@@ -61,6 +61,7 @@ extern VIEW  stdview;
 extern char	*setview(VIEW *v);
 extern void	normaspect(double va, double *ap, int *xp, int *yp);
 extern double	viewray(FVECT orig, FVECT direc, VIEW *v, double x, double y);
+extern int	jitteraperture(FVECT orig, FVECT direc, VIEW *v, double dia);
 extern int	viewloc(FVECT ip, VIEW *v, FVECT p);
 extern void	pix2loc(RREAL loc[2], RESOLU *rp, int px, int py);
 extern void	loc2pix(int pp[2], RESOLU *rp, double lx, double ly);

src/rt/rpict.c

@@ -1,5 +1,5 @@
 #ifndef lint
-static const char RCSid[] = "$Id: rpict.c,v 2.96 2021/12/03 16:50:05 greg Exp $";
+static const char RCSid[] = "$Id: rpict.c,v 2.97 2021/12/03 18:10:48 greg Exp $";
 #endif
 /*
  *  rpict.c - routines and variables for picture generation.
@@ -662,7 +662,7 @@ pixvalue(		/* compute pixel value */
 {
 	RAY  thisray;
 	FVECT	lorg, ldir;
-	double	hpos, vpos, vdist, lmax;
+	double	hpos, vpos, lmax;
 	int	i;
 						/* compute view ray */
 	setcolor(col, 0.0, 0.0, 0.0);
@@ -671,8 +671,6 @@ pixvalue(		/* compute pixel value */
 	if ((thisray.rmax = viewray(thisray.rorg, thisray.rdir,
 					&ourview, hpos, vpos)) < -FTINY)
 		return(0.0);
-
-	vdist = ourview.vdist;
 						/* set pixel index */
 	samplendx = pixnumber(x,y,hres,vres);
 						/* optional motion blur */
@@ -687,45 +685,10 @@ pixvalue(		/* compute pixel value */
 		}
 		if (normalize(thisray.rdir) == 0.0)
 			return(0.0);
-		vdist = (1.-d)*vdist + d*lastview.vdist;
-	}
-						/* optional depth-of-field */
-	if (dblur > FTINY) {
-		double  vc, df[2];
-						/* random point on disk */
-		SDsquare2disk(df, frandom(), frandom());
-		df[0] *= .5*dblur;
-		df[1] *= .5*dblur;
-		if ((ourview.type == VT_PER) | (ourview.type == VT_PAR)) {
-			double	adj = 1.0;
-			if (ourview.type == VT_PER)
-				adj /= DOT(thisray.rdir, ourview.vdir);
-			df[0] /= sqrt(ourview.hn2);
-			df[1] /= sqrt(ourview.vn2);
-			for (i = 3; i--; ) {
-				vc = ourview.vp[i] + adj*vdist*thisray.rdir[i];
-				thisray.rorg[i] += df[0]*ourview.hvec[i] +
-							df[1]*ourview.vvec[i] ;
-				thisray.rdir[i] = vc - thisray.rorg[i];
-			}
-		} else {			/* non-standard view case */
-			double	dfd = PI/4.*dblur*(.5 - frandom());
-			if ((ourview.type != VT_ANG) & (ourview.type != VT_PLS)) {
-				if (ourview.type != VT_CYL)
-					df[0] /= sqrt(ourview.hn2);
-				df[1] /= sqrt(ourview.vn2);
-			}
-			for (i = 3; i--; ) {
-				vc = ourview.vp[i] + vdist*thisray.rdir[i];
-				thisray.rorg[i] += df[0]*ourview.hvec[i] +
-							df[1]*ourview.vvec[i] +
-							dfd*ourview.vdir[i] ;
-				thisray.rdir[i] = vc - thisray.rorg[i];
-			}
-		}
-		if (normalize(thisray.rdir) == 0.0)
-			return(0.0);
 	}
+						/* depth-of-field */
+	if (!jitteraperture(thisray.rorg, thisray.rdir, &ourview, dblur))
+		return(0.0);
 
 	rayorigin(&thisray, PRIMARY, NULL, NULL);