Index: propedit.c
===================================================================
--- propedit.c	(revision 31101)
+++ propedit.c	(revision 31102)
@@ -201,6 +201,31 @@
 	return 0;
 }
 
+static const char pcb_acts_proptoggle[] = "proptoggle([scope], name, value)";
+static const char pcb_acth_proptoggle[] = "Toggle the named property of scope or all selected objects, assuming the property is boolean. Scope is documented at PropEdit().";
+fgw_error_t pcb_act_proptoggle(fgw_arg_t *res, int argc, fgw_arg_t *argv)
+{
+	const char *first, *name;
+	pcb_propedit_t ctx;
+
+	pcb_props_init(&ctx, PCB);
+
+	RND_ACT_CONVARG(1, FGW_STR, propset, first = argv[1].val.str);
+	if (prop_scope_add(&ctx, first, 1) == 0) {
+		RND_ACT_CONVARG(2, FGW_STR, propset, name = argv[2].val.str);
+	}
+	else {
+		name = first;
+		ctx.selection = 1;
+	}
+
+	RND_ACT_IRES(pcb_propsel_toggle(&ctx, name));
+
+	prop_scope_finish(&ctx);
+	pcb_props_uninit(&ctx);
+	return 0;
+}
+
 static const char pcb_acts_propget[] = "propget([scope], name, [stattype])";
 static const char pcb_acth_propget[] = "Return the named property of scope or all selected objects to/by value. Scope is documented at PropEdit().";
 fgw_error_t pcb_act_propget(fgw_arg_t *res, int argc, fgw_arg_t *argv)
@@ -339,6 +364,7 @@
 	{"propedit", pcb_act_propedit, pcb_acth_propedit, pcb_acts_propedit},
 	{"propprint", pcb_act_propprint, pcb_acth_propprint, pcb_acts_propprint},
 	{"propset", pcb_act_propset, pcb_acth_propset, pcb_acts_propset},
+	{"proptoggle", pcb_act_proptoggle, pcb_acth_proptoggle, pcb_acts_proptoggle},
 	{"propget", pcb_act_propget, pcb_acth_propget, pcb_acts_propget}
 };
 
Index: propsel.c
===================================================================
--- propsel.c	(revision 31101)
+++ propsel.c	(revision 31102)
@@ -355,6 +355,20 @@
 	const char *key = st->name+2;
 	const char *orig = rnd_attribute_get(list, key);
 
+	if (st->toggle) {
+		if (orig == NULL) /* do not create non-existing attributes */
+			return;
+		if (rnd_istrue(orig)) {
+			rnd_attribute_put(list, key, "false");
+			st->set_cnt++;
+		}
+		else if (rnd_isfalse(orig)) {
+			rnd_attribute_put(list, key, "true");
+			st->set_cnt++;
+		}
+		return;
+	}
+
 	if ((orig != NULL) && (strcmp(orig, st->s) == 0))
 		return;
 
@@ -366,6 +380,11 @@
 {
 	const char *key = st->name+2;
 
+	if (st->toggle) {
+		set_attr_raw(st, &obj->Attributes);
+		return;
+	}
+
 	if (pcb_uchg_attr(st->pcb, obj, key, st->s) != 0)
 		return;
 
@@ -383,7 +402,11 @@
 	if (i != NULL) {
 		if (i->mask & PCB_FLAG_CLEARLINE)
 			pcb_obj_pre(obj);
-		pcb_flag_change(st->pcb, st->c ? PCB_CHGFLG_SET : PCB_CHGFLG_CLEAR, i->mask, obj->type, obj->parent.any, obj, obj);
+
+		if (st->toggle)
+			pcb_flag_change(st->pcb, PCB_CHGFLG_TOGGLE, i->mask, obj->type, obj->parent.any, obj, obj);
+		else
+			pcb_flag_change(st->pcb, st->c ? PCB_CHGFLG_SET : PCB_CHGFLG_CLEAR, i->mask, obj->type, obj->parent.any, obj, obj);
 		if (i->mask & PCB_FLAG_CLEARLINE)
 			pcb_obj_post(obj);
 		DONE1;
@@ -407,6 +430,9 @@
 		return;
 	}
 
+	if (st->toggle)
+		return; /* can't toggle anything else */
+
 	if (strncmp(st->name, "p/board/", 8) == 0) {
 		if ((strcmp(pn, "name") == 0) &&
 		    (pcb_board_change_name(rnd_strdup(st->s)))) DONE;
@@ -442,6 +468,9 @@
 		return 0;
 	}
 
+	if (st->toggle)
+		return 0; /* can't toggle anything else */
+
 	if (strncmp(st->name, "p/layer/", 8) == 0) {
 		if ((strcmp(pn, "name") == 0) &&
 		    (pcb_layer_rename_(layer, rnd_strdup(st->s), 1) == 0)) DONE0;
@@ -463,6 +492,9 @@
 		return;
 	}
 
+	if (st->toggle)
+		return; /* can't toggle anything else */
+
 	if (strncmp(st->name, "p/layer_group/", 14) == 0) {
 		if ((strcmp(pn, "name") == 0) &&
 		    (pcb_layergrp_rename_(grp, rnd_strdup(st->s), 1) == 0)) DONE;
@@ -478,6 +510,9 @@
 	if (net == NULL)
 		return;
 
+	if (st->toggle)
+		return; /* can't toggle anything else */
+
 	if (st->is_attr) {
 		const char *key = st->name+2;
 		const char *orig = rnd_attribute_get(&net->Attributes, key);
@@ -502,6 +537,9 @@
 
 	if (set_common(st, (pcb_any_obj_t *)line)) return;
 
+	if (st->toggle)
+		return; /* can't toggle anything else */
+
 	if (strncmp(st->name, "p/trace/", 8) == 0) {
 		if (st->is_trace && st->c_valid && (strcmp(pn, "thickness") == 0) &&
 		    pcb_chg_obj_1st_size(PCB_OBJ_LINE, line->parent.layer, line, NULL, st->c, st->c_absolute)) DONE;
@@ -553,6 +591,9 @@
 
 	if (set_common(st, (pcb_any_obj_t *)arc)) return;
 
+	if (st->toggle)
+		return; /* can't toggle anything else */
+
 	if (strncmp(st->name, "p/trace/", 8) == 0)  {
 		if (st->is_trace && st->c_valid && (strcmp(pn, "thickness") == 0) &&
 		    pcb_chg_obj_1st_size(PCB_OBJ_ARC, arc->parent.layer, arc, NULL, st->c, st->c_absolute)) DONE;
@@ -607,6 +648,8 @@
 
 	if (set_common(st, (pcb_any_obj_t *)gfx)) return;
 
+	if (st->toggle)
+		return; /* can't toggle anything else */
 
 	if (strncmp(st->name, "p/gfx/", 6) == 0) {
 		if (st->c_valid && (strcmp(pn, "sx") == 0)) {
@@ -633,6 +676,9 @@
 
 	if (set_common(st, (pcb_any_obj_t *)text)) return;
 
+	if (st->toggle)
+		return; /* can't toggle anything else */
+
 	if (strncmp(st->name, "p/text/", 7) == 0) {
 		pcb_opctx_t op;
 
@@ -677,8 +723,16 @@
 {
 	const char *pn = st->name + 8;
 
+	if (st->is_attr) {
+		set_attr_obj(st, (pcb_any_obj_t *)poly);
+		return;
+	}
+
 	if (set_common(st, (pcb_any_obj_t *)poly)) return;
 
+	if (st->toggle)
+		return; /* can't toggle anything else */
+
 	if (strncmp(st->name, "p/trace/", 8) == 0) {
 		if (st->is_trace && st->c_valid && (strcmp(pn, "clearance") == 0) &&
 		    pcb_chg_obj_clear_size(PCB_OBJ_POLY, poly->parent.layer, poly, NULL, st->c*2, st->c_absolute)) DONE;
@@ -685,11 +739,6 @@
 		if (st->is_trace && st->c_valid && (strcmp(pn, "enforce_clearance") == 0) &&
 		    pcb_chg_obj_enforce_clear_size(PCB_OBJ_POLY, poly->parent.layer, poly, NULL, st->c, st->c_absolute)) DONE;
 	}
-
-	if (st->is_attr) {
-		set_attr_obj(st, (pcb_any_obj_t *)poly);
-		return;
-	}
 }
 
 static void set_pstk(pcb_propset_ctx_t *st, pcb_pstk_t *ps)
@@ -706,6 +755,9 @@
 
 	if (set_common(st, (pcb_any_obj_t *)ps)) return;
 
+	if (st->toggle)
+		return; /* can't toggle anything else */
+
 	ca = st->c;
 	i = (st->c != 0);
 	proto = pcb_pstk_get_proto(ps);
@@ -793,6 +845,9 @@
 		return;
 	}
 
+	if (st->toggle)
+		return; /* can't toggle anything else */
+
 	if (strncmp(st->name, "p/subcircuit/", 13) == 0) {
 		pcb_opctx_t op;
 		rnd_coord_t x = 0, y = 0;
@@ -898,6 +953,8 @@
 	if ((prop[0] != 'a') && (prop[0] != 'p'))
 		return 0;
 
+	memset(&sctx, 0, sizeof(sctx));
+
 	if (value == NULL)
 		value = "";
 	sctx.s = value;
@@ -909,6 +966,7 @@
 	}
 	else
 		sctx.d_absolute = ((*start != '-') && (*start != '+'));
+	sctx.toggle = 0;
 	sctx.c = rnd_get_value_ex(start, NULL, &sctx.c_absolute, NULL, NULL, &sctx.c_valid);
 	sctx.d = strtod(start, &end);
 	sctx.d_valid = (*end == '\0');
@@ -917,6 +975,24 @@
 	return pcb_propsel_set(ctx, prop, &sctx);
 }
 
+int pcb_propsel_toggle(pcb_propedit_t *ctx, const char *prop)
+{
+	pcb_propset_ctx_t sctx;
+
+	/* sanity checks for invalid props */
+	if (prop[1] != '/')
+		return 0;
+	if ((prop[0] != 'a') && (prop[0] != 'p'))
+		return 0;
+
+	memset(&sctx, 0, sizeof(sctx));
+
+	sctx.toggle = 1;
+	sctx.set_cnt = 0;
+
+	return pcb_propsel_set(ctx, prop, &sctx);
+}
+
 /*******************/
 
 static long del_attr(void *ctx, rnd_attribute_list_t *list, const char *key)
Index: propsel.h
===================================================================
--- propsel.h	(revision 31101)
+++ propsel.h	(revision 31102)
@@ -33,6 +33,7 @@
 	double d;
 	rnd_color_t color;
 	rnd_bool c_absolute, d_absolute, c_valid, d_valid, clr_valid;
+	unsigned toggle:1; /* when 1, ignore value and attempt to toggle */
 
 	/* private */
 	unsigned is_trace:1;
@@ -46,6 +47,7 @@
 
 int pcb_propsel_set_str(pcb_propedit_t *ctx, const char *prop, const char *value);
 int pcb_propsel_set(pcb_propedit_t *ctx, const char *prop, pcb_propset_ctx_t *sctx);
+int pcb_propsel_toggle(pcb_propedit_t *ctx, const char *prop);
 int pcb_propsel_del(pcb_propedit_t *ctx, const char *attr_name);
 
 /* Allocate new string and print the value using current unit */