From fc1e11e4ca9572161ec6fac6372960777f069461 Mon Sep 17 00:00:00 2001
From: Lincoln de Sousa <lincoln@minaslivre.org>
Date: Tue, 12 Aug 2008 08:00:34 -0300
Subject: [PATCH] Adding the class Point, removing the attributes x and y from
 the Ball class and adding the p attr that is an instance of Point. Updating
 BallManager.save_to_file, Gzv.draw_ball to fit with the above change.

The feature "Move ball" was implemented and to do so, the event
motion-notify-event of the Gzv.treeview was binded to a new
callback (Gzv.ball_motion), Gzv.button_pressed now discovers if
the click was inside an already existent ball and were added
two new attributes to Gzv class: last_y and move_ball.
---
 gzv.py | 68 ++++++++++++++++++++++++++++++++++++++++++++++------------
 1 file changed, 54 insertions(+), 14 deletions(-)

diff --git a/gzv.py b/gzv.py
index 752c117..6c0d4dc 100644
--- a/gzv.py
+++ b/gzv.py
@@ -1,3 +1,4 @@
+# -*- coding: utf-8; -*-
 # gzv.py - an user interface to generate-zooming-video
 #
 # Copyright (C) 2008  Lincoln de Sousa <lincoln@minaslivre.org>
@@ -22,14 +23,22 @@ from ConfigParser import ConfigParser
 
 _ = lambda x:x
 
+class Point(object):
+    def __init__(self, x, y):
+        self.x = x
+        self.y = y
+
+    @staticmethod
+    def pythagorean(p1, p2):
+        return math.sqrt((p2.x - p1.x)**2 + (p2.y - p2.y)**2)
+
 class Ball(object):
     DEFAULT_WIDTH = 10
 
     def __init__(self, x, y, r, name='', position=0, selected=False):
         self.position = position
         self.selected = selected
-        self.x = int(x)
-        self.y = int(y)
+        self.p = Point(int(x), int(y))
         self.radius = int(r)
         self.name = name
 
@@ -40,7 +49,7 @@ class BallManager(list):
     def save_to_file(self, path):
         target = open(path, 'w')
         for i in self:
-            target.write('%d,%d %d %s\n' % (i.x, i.y, i.radius, i.name))
+            target.write('%d,%d %d %s\n' % (i.p.x, i.p.y, i.radius, i.name))
         target.close()
 
 class GladeLoader(object):
@@ -138,6 +147,7 @@ class Gzv(GladeLoader):
         self.evtbox.connect('button-press-event', self.button_press)
         self.evtbox.connect('button-release-event', self.button_release)
         self.evtbox.connect('motion-notify-event', self.motion_notify)
+        self.evtbox.connect('motion-notify-event', self.ball_motion)
 
         # making it possible to grab motion events when the mouse is
         # over the widget.
@@ -162,11 +172,13 @@ class Gzv(GladeLoader):
         self.setup_treeview()
 
         self.new_ball = False
+        self.move_ball = None
 
         # drawing stuff
         self.start_x = -1
         self.start_y = -1
         self.last_x = -1
+        self.last_y = -1
         self.radius = Ball.DEFAULT_WIDTH
 
     def show(self):
@@ -326,33 +338,47 @@ class Gzv(GladeLoader):
         if self.start_x < 0:
             return False
 
-        ball = Ball(self.start_x, self.start_y, self.radius)
-        self.draw_ball(ball)
+        if self.new_ball:
+            ball = Ball(self.start_x, self.start_y, self.radius)
+            self.draw_ball(ball)
 
         return False
 
     def draw_ball(self, ball):
         ctx = self.draw.window.cairo_create()
-        ctx.arc(ball.x, ball.y, ball.radius, 0, 64*math.pi)
+        ctx.arc(ball.p.x, ball.p.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.x, ball.y, ball.radius+1, 0, 64*math.pi)
+            ctx.arc(ball.p.x, ball.p.y, ball.radius+1, 0, 64*math.pi)
             ctx.stroke()
 
     def button_press(self, widget, event):
         self.new_ball = True
 
+        self.last_x = event.x
+        self.last_y = event.y
+
         if event.button == 1:
+            for i in self.balls:
+                p1 = Point(event.x, event.y)
+                p2 = Point(i.p.x, i.p.y)
+                if Point.pythagorean(p1, p2) < i.radius:
+                    self.last_x = event.x - i.p.x
+                    self.last_y = event.y - i.p.y
+
+                    self.new_ball = False
+                    self.move_ball = i
+                    break
+
             self.start_x = event.x
             self.start_y = event.y
-            self.last_x = event.x
 
     def button_release(self, widget, event):
-        self.new_ball = False
+        self.move_ball = None
 
         if event.button == 1:
             self.finish_drawing()
@@ -370,12 +396,26 @@ class Gzv(GladeLoader):
 
         self.last_x = event.x
 
+    def ball_motion(self, widget, event):
+        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.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):
-        position = len(self.balls)
-        ball = Ball(self.start_x, self.start_y, self.radius, '', position)
-        self.balls.append(ball)
-        self.model.append([position, ''])
-        self.treeview.set_cursor(str(position), self.fpcolumn, True)
+        if self.new_ball:
+            position = len(self.balls)
+            ball = Ball(self.start_x, self.start_y, self.radius, '', position)
+            self.balls.append(ball)
+            self.model.append([position, ''])
+            self.treeview.set_cursor(str(position), self.fpcolumn, True)
+            self.new_ball = False
 
         # reseting to the default coordenades
         self.start_x = -1
-- 
2.20.1