diff --git a/Fonderie/crapulator.c b/Fonderie/crapulator.c
index af46fc3..1d32ed7 100644
--- a/Fonderie/crapulator.c
+++ b/Fonderie/crapulator.c
@@ -92,6 +92,7 @@ FimgFilter3x3	lowpass = {
 	};
 
 FimgFilter3x3	hipass = {
+	/* there was a bug with this filter */
 		{
 		-1.0,	-1.0,	-1.0,
 		-1.0,	 9.0,	-1.0,
@@ -101,6 +102,7 @@ FimgFilter3x3	hipass = {
 	};
 
 FimgFilter3x3	diagonal = {
+	/* there was a bug with this filter */
 		{
 		4.0,	1.0,	0.0,
 		1.0,	0.0,	-1.0,
@@ -354,8 +356,9 @@ switch (idFx) {
 		retval = des_bords_sombres_a(image, 160);
 		break;
 	case CR_bsombrb:			/* experiment ! */
-		retval = des_bords_sombres_b(image, 160);
+		retval = des_bords_sombres_b(image, 100);
 		break;
+
 	case CR_vsglitch:
 		/* please make this function more tweakable */
 		retval = vertical_singlitch(image, 290+rand()%45,
diff --git a/Fonderie/sfx.c b/Fonderie/sfx.c
index dc7efda..a826eaa 100644
--- a/Fonderie/sfx.c
+++ b/Fonderie/sfx.c
@@ -56,7 +56,13 @@ int		x, y, pline, off;
 
 for (y=pos[1]; y<pos[1]+pos[3]; y++) {
 	pline = y*pimg->width;
-	for (x=pos[0]+2; x<pos[0]+pos[2]-2; x++) {
+#if 0
+	for (x=0; x<(pos[0]+pos[2]); x++) {
+		off = pline + x;
+		pimg->R[off]=pimg->G[off]=pimg->B[off]=0.0;
+		}
+#endif
+	for (x=pos[0]+2; x<(pos[0]+pos[2]-2); x++) {
 		off = pline + x;
 		/* wtf i'm doing here ? */
 		pimg->R[off] = fvals[0];
@@ -320,21 +326,39 @@ return 0;
 /* -------------------------------------------------------------- */
 /* nouveau Mon 10 May 2021 08:46:02 PM CEST
  *	chez Eric 1KA						*/
-int des_bords_sombres_b(FloatImg *pimg, int offset)
+int des_bords_sombres_b(FloatImg *pimg, int nbre)
 {
-
+int		idx, x, foo;
+float		coef, *fptr;
 #if DEBUG_LEVEL
 fprintf(stderr, ">>> %s ( %p %d )\n", __func__, pimg, offset);
 #endif
 
-if (offset<0 || offset>=pimg->width) {
-	fprintf(stderr, "%s: offset %d is bad\n", __func__, offset);
-	return -66;
+for (idx=0; idx<nbre; idx++) {
+
+	coef = (float)idx / (float)nbre;
+
+	fptr = pimg->R + (idx*pimg->width);
+	for (x=0; x<pimg->width; x++) *fptr++ *= coef;
+	fptr = pimg->G + (idx*pimg->width);
+	for (x=0; x<pimg->width; x++) *fptr++ *= coef;
+	fptr = pimg->B + (idx*pimg->width);
+	for (x=0; x<pimg->width; x++) *fptr++ *= coef;
+
+	foo = (pimg->height-idx) - 1;
+	fptr = pimg->R + (foo*pimg->width);
+	// fprintf(stderr, "%5d   %9.3f    %p\n", foo, coef, fptr);
+	for (x=0; x<pimg->width; x++) *fptr++ *= coef;
+	fptr = pimg->G + (foo*pimg->width);
+	for (x=0; x<pimg->width; x++) *fptr++ *= coef;
+	fptr = pimg->B + (foo*pimg->width);
+	for (x=0; x<pimg->width; x++) *fptr++ *= coef;
+
 	}
 
-fprintf(stderr, "ERROR: %s not implemented\n", __func__);
+// fprintf(stderr, "WARNING: %s badly implemented\n", __func__);
 
-return -1;
+return 0;
 }
 /* -------------------------------------------------------------- */
 /*
diff --git a/floatimg.h b/floatimg.h
index 5aec108..d836480 100644
--- a/floatimg.h
+++ b/floatimg.h
@@ -4,7 +4,7 @@
  *	http://la.buvette.org/photos/cumul
  */
 
-#define		FIMG_VERSION	157
+#define		FIMG_VERSION	158
 
 /*
  *	in memory descriptor
diff --git a/funcs/Makefile b/funcs/Makefile
index cc66522..b2ec18f 100644
--- a/funcs/Makefile
+++ b/funcs/Makefile
@@ -7,7 +7,7 @@ COPT = -Wall -fpic -g -no-pie  -DDEBUG_LEVEL=0
 DEPS = ../floatimg.h Makefile
 
 OBJS = fimg-png.o fimg-tiff.o misc-plots.o filtrage.o utils.o	\
-	fimg-libpnm.o rampes.o 					\
+	fimg-libpnm.o rampes.o rectangle.o			\
 	sfx0.o sfx1.o sfx2.o sfx3.o sfx4.o			\
 	geometry.o rotate.o fimg-openexr.o			\
 	equalize.o fimg-fits.o saturation.o histogram.o		\
@@ -37,6 +37,9 @@ tests.o:	tests.c tests.h $(DEPS)
 
 # ###
 
+rectangle.o:		rectangle.c  $(DEPS)
+	gcc $(COPT) -c $<
+
 decomprgb.o:		decomprgb.c  $(DEPS)
 	gcc $(COPT) -c $<
 
diff --git a/funcs/rectangle.c b/funcs/rectangle.c
new file mode 100644
index 0000000..83da174
--- /dev/null
+++ b/funcs/rectangle.c
@@ -0,0 +1,32 @@
+/*
+ *			R E C T A N G L E
+ *		This is an eternal WIP, sorry...
+ */
+
+#include  <stdio.h>
+#include  <stdlib.h>
+#include  <stdint.h>
+#include  <math.h>
+
+#include  "../floatimg.h"
+
+/* --------------------------------------------------------------------- */
+int fimg_clear_rectangle(FloatImg *pi, int coo[4])
+{
+int		line, off;
+
+#if DEBUG_LEVEL
+fprintf(stderr, ">>> %s ( %p %p )\n", __func__, pi, coo);
+#endif
+
+	/* please add boudary checks */
+
+for (line=0; line<coo[3]; line++) {
+	off = (line+coo[1])*pi->width + coo[0];
+	fprintf(stderr, "line %d off %d\n", line, off);
+	}
+
+return -1;
+}
+/* --------------------------------------------------------------------- */
+