From 5a599e14f6e5ef17ab80ed09148fbb949ecf5bf6 Mon Sep 17 00:00:00 2001
From: Werner Almesberger <werner@almesberger.net>
Date: Sun, 18 Mar 2012 17:57:04 -0300
Subject: [PATCH] cameo: don't duplicate paths already cleared by the outline

Also pass information on whether we're about to enter or leave a
polygon.
---
 cameo/area.c | 33 ++++++++++++++++++---------------
 1 file changed, 18 insertions(+), 15 deletions(-)

diff --git a/cameo/area.c b/cameo/area.c
index 17a8ccf..953f472 100644
--- a/cameo/area.c
+++ b/cameo/area.c
@@ -182,7 +182,7 @@ printf("\tna %g (%g) nb %g (%g)\n", na, fx+tx*na, nb, fx+tx*nb);
 
 
 static int hit_path(double fx, double fy, double tx, double ty,
-    const struct path *path, int inside, double r, double *x)
+    const struct path *path, int inside, int enter, double r, double *x)
 {
 	const struct point *p;
 	int left;
@@ -234,7 +234,8 @@ static const struct path **subordinates(const struct path *paths,
 
 
 static void do_line(const struct path *path, const struct path **sub,
-    double xa, double xb, double y, double r_tool, struct path **res)
+    double xa, double xb, double y, double r_tool, double overlap,
+    struct path **res)
 {
 	const struct path *last = path;
 	const struct path **s;
@@ -242,25 +243,27 @@ static void do_line(const struct path *path, const struct path **sub,
 	double x, next;
 
 printf("  y=%g\n", y);
-	if (!hit_path(xa-3*r_tool, y, xb, y, last, 1, r_tool, &x))
+	if (!hit_path(xa-3*r_tool, y, xb, y, last, 1, 0, r_tool, &x))
 		return;
 	while (1) {
 printf("    x=%g\n", x);
 		next = xb;
 		last = NULL;
-		if (hit_path(x, y, xb, y, path, 1, r_tool, &next))
+		if (hit_path(x, y, xb, y, path, 1, 1, r_tool, &next))
 			last = path;
 		for (s = sub; *s; s++)
-			if (hit_path(x, y, next, y, *s, 0, r_tool, &next))
+			if (hit_path(x, y, next, y, *s, 0, 1, r_tool, &next))
 				last = *s;
-		new = path_new(r_tool, "");
-		path_add(new, x, y, path->first->z);
-		path_add(new, next, y, path->first->z);
-		new->next = *res;
-		*res = new;
+		if (next-x > 2*r_tool-2*overlap) {
+			new = path_new(r_tool, "");
+			path_add(new, x, y, path->first->z);
+			path_add(new, next, y, path->first->z);
+			new->next = *res;
+			*res = new;
+		}
 		if (!last)
 			return;
-		if (!hit_path(next+EPSILON, y, xb, y, last, last == path,
+		if (!hit_path(next+EPSILON, y, xb, y, last, last == path, 0,
 		    r_tool, &x))
 			return;
 	}
@@ -291,14 +294,14 @@ static void fill_path(const struct path *paths, const struct path *path,
 		return;
 	sub = subordinates(paths, path);
 	xa += r_tool;
-	ya += r_tool;
+	ya += 3*r_tool-overlap;
 	xb -= r_tool;
-	yb -= r_tool;
+	yb -= 3*r_tool-overlap;
 	n = ceil((yb-ya)/(2*r_tool-overlap));
 printf("x[%g:%g] y[%g:%g] n=%d\n", xa, xb, ya, yb, n);
 	for (i = 0; i <= n; i++)
-		do_line(path, sub, xa, xb, ya+(yb-ya)*((double) i/n), r_tool,
-		    res);
+		do_line(path, sub, xa, xb, ya+(yb-ya)*((double) i/n),
+		    r_tool, overlap, res);
 	for (s = sub; *s; s++) {
 		sub2 = subordinates(paths, *s);
 		for (s2 = sub2; *s2; s2++)