Add demo; fix bug

2 files changed, 149 insertions, 7 deletions

diff --git a/demo.c b/demo.c
new file mode 100644
index 0000000..712d12e
--- /dev/null
+++ b/demo.c
@@ -0,0 +1,126 @@
+#include <gtk/gtk.h>
+#include <glib.h>
+#include <cairo.h>
+
+#define NO_MAIN
+#include "region-iter.c"
+
+static const pixman_rectangle32_t rects[] = {
+    { 0, 50, 200, 100 },
+    { 250, 0, 200, 100 },
+    { 500, 0, 50, 350 },
+    { 400, 100, 50, 100 },
+    { 100, 150, 50, 50 },
+    { 50, 200, 150, 150 },
+    { 0, 300, 50, 50 },
+    { 200, 250, 100, 100 },
+    { 250, 150, 100, 100 },
+    { 350, 200, 100, 150 },
+    { 250, 350, 150, 50 },
+    { 450, 350, 50, 50 },
+    { 50, 450, 400, 50 },
+    { 25, 135, 600, 25 }
+};
+
+static corner_t *
+make_path (int *n_corners)
+{
+    corner_t *corners;
+    pixman_region32_t region;
+    int i;
+
+    pixman_region32_init (&region);
+
+    for (i = 0; i < sizeof (rects) / sizeof (rects[0]); ++i)
+    {
+	pixman_region32_union_rect (&region, &region,
+				    rects[i].x, rects[i].y,
+				    rects[i].width, rects[i].height);
+    }
+
+    corners = region_path (&region, n_corners);
+
+    pixman_region32_fini (&region);
+
+    return corners;
+}
+
+static gboolean
+on_expose (GtkWidget *widget, GdkEvent *event, gpointer data)
+{
+    cairo_t *cr;
+    int i;
+
+    if (GTK_WIDGET_DRAWABLE (widget))
+    {
+	corner_t *corners;
+	int n_corners;
+	int new = 0;
+
+        cr = gdk_cairo_create (widget->window);
+
+	for (i = 0; i < sizeof (rects) / sizeof (rects[0]); ++i)
+	{
+	    cairo_rectangle (cr,
+			     rects[i].x, rects[i].y,
+			     rects[i].width, rects[i].height);
+
+	    cairo_set_source_rgba (cr, 0, 0, 0.7, 0.7);
+	    cairo_fill (cr);
+	}
+
+	corners = make_path (&n_corners);
+
+	for (i = 0; i < n_corners; ++i)
+	{
+	    corner_t *corner = &(corners[i]);
+
+	    cairo_move_to (cr, corner->x, corner->y);
+
+	    while (corner->next != -1)
+	    {
+		corner_t *next = &(corners[corner->next]);
+
+		cairo_line_to (cr, next->x, next->y);
+
+		corner->next = -1;
+		corner = next;
+	    }
+	}
+
+	cairo_set_source_rgba (cr, 0.2, 0.8, 0.2, 0.6);
+
+	cairo_fill_preserve (cr);
+
+	cairo_set_source_rgba (cr, 0.0, 0.3, 0.0, 0.8);
+
+	cairo_stroke (cr);
+
+	free (corners);
+
+	cairo_destroy (cr);
+    }
+
+    return TRUE;
+}
+
+int
+main (int argc, char **argv)
+{
+    GtkWindow *window;
+
+    gtk_init (&argc, &argv);
+
+    window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
+
+    gtk_window_set_default_size (window, 1200, 768);
+
+    g_signal_connect (window, "expose_event", G_CALLBACK (on_expose), NULL);
+
+    gtk_widget_show_all (window);
+
+    gtk_main ();
+
+    return 0;
+
+}
diff --git a/region-iter.c b/region-iter.c
index 37e9222..9820200 100644
--- a/region-iter.c
+++ b/region-iter.c
@@ -4,8 +4,12 @@
 #include <limits.h>
 #include <assert.h>
 
+#ifndef TRUE
 #define TRUE 1
+#endif
+#ifndef FALSE
 #define FALSE 0
+#endif
 
 static const pixman_box32_t sentinel =
 {
@@ -75,6 +79,7 @@ region_iter_init (region_iter_t *iter, pixman_region32_t *region)
 {
     iter->y = INT_MIN;
     iter->first_row = TRUE;
+    iter->final_row = FALSE;
 
     if (!region->data)
     {
@@ -109,7 +114,7 @@ region_iter_get_row (region_iter_t *iter, row_t *row)
 
 	iter->final_row = FALSE;
 	iter->first = NULL;
-	
+
 	return TRUE;
     }
     else if (iter->first_row || iter->y < iter->first->y1)
@@ -472,7 +477,7 @@ region_path (pixman_region32_t *region, int *n)
 	int *old_active;
 	int old_n_active;
 	int current;
-	
+
 	old_active = active;
 	old_n_active = n_active;
 
@@ -493,7 +498,7 @@ region_path (pixman_region32_t *region, int *n)
 		       corners[old_active[current]].x <= x2)
 		{
 		    int c = old_active[current];
-		    
+
 		    if (corners[c].x == x1)
 			p1 = c;
 		    else if (corners[c].x == x2)
@@ -509,7 +514,7 @@ region_path (pixman_region32_t *region, int *n)
 		corners[c1].y = row1.y2;
 		corners[c2].x = x2;
 		corners[c2].y = row1.y2;
-				
+
 		if (p1 != -1)
 		{
 		    if (type == ROW1)
@@ -543,14 +548,20 @@ region_path (pixman_region32_t *region, int *n)
 
 	while (current < old_n_active)
 	    active = add_active (active, &n_active, old_active[current++]);
-	
-	free (old_active);
 
+#if 0
+	int i;
+	printf ("active:\n");
+	for (i = 0; i < n_active; ++i)
+	    printf (" %d %d, ", corners[active[i]].x, corners[active[i]].y);
+	printf ("\n");
+#endif
+
+	free (old_active);
 	row1 = row2;
     }
 
     *n = n_corners;
-    
     return corners;
 }
 
@@ -578,6 +589,8 @@ dump_corners (corner_t *corners, int n_corners)
 }
 
 
+#ifndef NO_MAIN
+
 int
 main ()
 {
@@ -705,3 +718,6 @@ main ()
 
     return 0;
 }
+
+#endif
+