roi: Move rubberband bounds check into do_roi

1 files changed, 31 insertions, 30 deletions

diff --git a/roi.c b/roi.c
index 173832c..9192472 100644
--- a/roi.c
+++ b/roi.c
@@ -16,18 +16,28 @@ struct roi {
 
 	GdkPixbuf *input, *modified_input;
 
-	cairo_rectangle_t area;
-
 	gboolean doing_rubberband;
 	struct {
 		double x1, y1, x2, y2;
 	} rubberband;
 };
 
-static void
+static inline void
+calc_rubberband_rect(struct roi *roi,
+		     double *x, double *y,
+		     double *width, double *height)
+{
+	*x = MIN(roi->rubberband.x1, roi->rubberband.x2);
+	*y = MIN(roi->rubberband.y1, roi->rubberband.y2);
+	*width  = ABS(roi->rubberband.x1 - roi->rubberband.x2);
+	*height = ABS(roi->rubberband.y1 - roi->rubberband.y2);
+}
+
+static gboolean
 do_roi(struct roi *roi)
 {
 	GdkPixbuf *match;
+	cairo_rectangle_t area;
 	int x, y, i;
 	int width, height;
 	gint stride, nch;
@@ -39,18 +49,23 @@ do_roi(struct roi *roi)
 		gint min, max;
 	} interval[3];
 
+	calc_rubberband_rect(roi, &area.x, &area.y, &area.width, &area.height);
+
+	if (area.width < 1 || area.height < 1)
+		return FALSE;
+
 	match = gdk_pixbuf_new_subpixbuf(roi->input, 
-					 roi->area.x,
-					 roi->area.y,
-					 roi->area.width,
-					 roi->area.height);
+					 area.x,
+					 area.y,
+					 area.width,
+					 area.height);
 	nch = gdk_pixbuf_get_n_channels(match);
 	stride = gdk_pixbuf_get_rowstride(match);
-	s = roi->area.width * roi->area.height;
+	s = area.width * area.height;
 
 	for (y = 0, row = gdk_pixbuf_get_pixels(match);
-	     y < roi->area.height; ++y, row += stride) {
-		for (x = 0, pix = row; x < roi->area.width; ++x, pix += nch) {
+	     y < area.height; ++y, row += stride) {
+		for (x = 0, pix = row; x < area.width; ++x, pix += nch) {
 			for (i = 0; i < 3; ++i)
 				middle[i] += pix[i];
 		}
@@ -59,8 +74,8 @@ do_roi(struct roi *roi)
 		middle[i] /= s;
 
 	for (y = 0, row = gdk_pixbuf_get_pixels(match);
-	     y < roi->area.height; ++y, row += stride) {
-		for (x = 0, pix = row; x < roi->area.width; ++x, pix += nch) {
+	     y < area.height; ++y, row += stride) {
+		for (x = 0, pix = row; x < area.width; ++x, pix += nch) {
 			for (i = 0; i < 3; ++i)
 				sigma[i] +=
 					(pix[i] - middle[i]) *
@@ -105,6 +120,8 @@ do_roi(struct roi *roi)
 	}
 
 	g_object_unref(match);
+
+	return TRUE;
 }
 
 static gboolean
@@ -140,17 +157,6 @@ button_press_event(GtkWidget *widget, GdkEventButton *event, gpointer userdata)
 	}
 }
 
-static inline void
-calc_rubberband_rect(struct roi *roi,
-		     double *x, double *y,
-		     double *width, double *height)
-{
-	*x = MIN(roi->rubberband.x1, roi->rubberband.x2);
-	*y = MIN(roi->rubberband.y1, roi->rubberband.y2);
-	*width  = ABS(roi->rubberband.x1 - roi->rubberband.x2);
-	*height = ABS(roi->rubberband.y1 - roi->rubberband.y2);
-}
-
 static gboolean
 button_release_event(GtkWidget *widget, GdkEventButton *event, gpointer userdata)
 {
@@ -159,15 +165,10 @@ button_release_event(GtkWidget *widget, GdkEventButton *event, gpointer userdata
 	if (event->button != GDK_BUTTON_PRIMARY)
 		return TRUE;
 
-	calc_rubberband_rect(roi, &roi->area.x, &roi->area.y, 
-			     &roi->area.width, &roi->area.height);
-
-	if (roi->area.width > 0 && roi->area.height > 0)
-		do_roi(roi);
-
 	roi->doing_rubberband = FALSE;
 
-	gtk_widget_queue_draw(roi->drawing_area);
+	if (do_roi(roi))
+		gtk_widget_queue_draw(roi->drawing_area);
 
 	return FALSE;
 }