fixing issues when the image does not fill the whole allocated

area. Added methods: Gzv.ball_with_border, Gzv.point_without_border.
Changed methods: Gzv.button_press, Gzv.draw_ball

diff --git a/gzv.py b/gzv.py
index ca94af9..6d591fc 100644 (file)
--- a/gzv.py
+++ b/gzv.py
@@ -344,16 +344,38 @@ class Gzv(GladeLoader):
 
         return False
 
+    def ball_width_border(self, ball):
+        iw, ih = self.draw.size_request()
+        w = self.draw.get_allocation().width
+        h = self.draw.get_allocation().height
+
+        x = ((w / 2) - (iw / 2)) + ball.p.x
+        y = ((h / 2) - (ih / 2)) + ball.p.y
+        return Point(x, y)
+
+    def point_without_border(self, point):
+        iw, ih = self.draw.size_request()
+        w = self.draw.get_allocation().width
+        h = self.draw.get_allocation().height
+
+        x = point.x - ((w / 2) - (iw / 2))
+        y = point.y - ((h / 2) - (ih / 2))
+        return Point(x, y)
+
     def draw_ball(self, ball):
         ctx = self.draw.window.cairo_create()
-        ctx.arc(ball.p.x, ball.p.y, ball.radius, 0, 64*math.pi)
+        ctx.arc(self.ball_width_border(ball).x,
+                self.ball_width_border(ball).y,
+                ball.radius, 0, 64*math.pi)
         ctx.set_source_rgba(0.0, 0.0, 0.5, 0.4)
         ctx.fill()
 
         if ball.selected:
             ctx.set_source_rgba(0.0, 0.5, 0.0, 0.4)
             ctx.set_line_width(5)
-            ctx.arc(ball.p.x, ball.p.y, ball.radius+1, 0, 64*math.pi)
+            ctx.arc(self.ball_width_border(ball).x,
+                    self.ball_width_border(ball).y,
+                    ball.radius+1, 0, 64*math.pi)
             ctx.stroke()
 
     def button_press(self, widget, event):
@@ -365,7 +387,7 @@ class Gzv(GladeLoader):
         if event.button == 1:
             for i in self.balls:
                 p1 = Point(event.x, event.y)
-                p2 = Point(i.p.x, i.p.y)
+                p2 = self.ball_width_border(i)
                 if Point.pythagorean(p1, p2) < i.radius:
                     self.last_x = event.x - i.p.x
                     self.last_y = event.y - i.p.y
@@ -374,8 +396,8 @@ class Gzv(GladeLoader):
                     self.move_ball = i
                     break
 
-            self.start_x = event.x
-            self.start_y = event.y
+            self.start_x = self.point_without_border(event).x
+            self.start_y = self.point_without_border(event).y
 
     def button_release(self, widget, event):
         self.move_ball = None
@@ -400,14 +422,11 @@ class Gzv(GladeLoader):
         if not self.move_ball:
             return
 
-        self.move_ball.p.x += (event.x - self.move_ball.p.x)
-        self.move_ball.p.y += (event.y - self.move_ball.p.y)
+        self.move_ball.p.x = self.point_without_border(event).x
+        self.move_ball.p.y = self.point_without_border(event).y
 
         self.draw.queue_draw()
 
-        self.last_x = event.x - self.move_ball.p.x
-        self.last_y = event.y - self.move_ball.p.y
-
     def finish_drawing(self):
         if self.new_ball:
             position = len(self.balls)