From 6b7cecaf5f58f5d564b4d2d91ffd178f1eb92074 Mon Sep 17 00:00:00 2001
From: Werner Almesberger <werner@almesberger.net>
Date: Thu, 8 Jan 2015 09:12:05 -0300
Subject: [PATCH] slicer/slice.c, slice.h: optionally draw a box around the
 object

---
 slicer/slice.c | 56 ++++++++++++++++++++++++++++++++++++++++++++++++--
 slicer/slice.h |  2 +-
 2 files changed, 55 insertions(+), 3 deletions(-)

diff --git a/slicer/slice.c b/slicer/slice.c
index cdc05aa..465eea7 100644
--- a/slicer/slice.c
+++ b/slicer/slice.c
@@ -38,6 +38,35 @@ struct z {
 static GTree *tree;
 
 
+/* ----- Bounding box ------------------------------------------------------ */
+
+
+static bool first = 1;
+static float min_x, max_x, min_y, max_y;
+
+
+static void bbox(float x, float y)
+{
+	if (first) {
+		min_x = max_x = x;
+		min_y = max_y = y;
+		first = 0;
+	} else {
+		if (x < min_x)
+			min_x = x;
+		if (y < min_y)
+			min_y = y;
+		if (x > max_x)
+			max_x = x;
+		if (y > max_y)
+			max_y = y;
+	}
+}
+
+
+/* ----- Data collection --------------------------------------------------- */
+
+
 static inline bool eq(float a, float b)
 {
 	return fabsf(a - b) < 1e-6;
@@ -91,6 +120,9 @@ fprintf(stderr, "zero point\n");
 		exit(1);
 	}
 
+	bbox(a->x, a->y);
+	bbox(b->x, b->y);
+
 	z = get_z(a->z);
 	line = alloc_type(struct line);
 	line->ax = a->x;
@@ -152,9 +184,30 @@ static gboolean dump_range(gpointer key, gpointer value, gpointer data)
 }
 
 
-void slice_dump(void)
+static gboolean dump_box(gpointer key, gpointer value, gpointer data)
+{
+	const struct z *z = value;
+	float box = *(float *) data;
+
+	if (!z->present)
+		return 0;
+
+	printf("%f %f %f\n%f %f %f\n%f %f %f\n%f %f %f\n%f %f %f\n\n\n",
+	    min_x - box, min_y - box, z->z,
+	    max_x + box, min_y - box, z->z,
+	    max_x + box, max_y + box, z->z,
+	    min_x - box, max_y + box, z->z,
+	    min_x - box, min_y - box, z->z);
+	
+	return 0;
+}
+
+
+void slice_dump(float box)
 {
 	g_tree_foreach(tree, dump_range, NULL);
+	if (box && !first)
+		g_tree_foreach(tree, dump_box, &box);
 }
 
 
@@ -167,7 +220,6 @@ static gint comp(gconstpointer a, gconstpointer b)
 	const float *zb = b;
 
 	return eq(*za, *zb) ? 0 : *za < *zb ? -1 : 1;
-
 }
 
 
diff --git a/slicer/slice.h b/slicer/slice.h
index fbaa9ac..1772b61 100644
--- a/slicer/slice.h
+++ b/slicer/slice.h
@@ -18,7 +18,7 @@
 
 
 void slice(struct v f[3]);
-void slice_dump(void);
+void slice_dump(float box);
 void slice_init(void);
 
 #endif /* !SLICE_H */