Merge git+ssh://wadeb@dev.laptop.org/git/users/wadeb/math

Conflicts:

	mathactivity.py

1 files changed, 134 insertions, 36 deletions

diff --git a/mathactivity.py b/mathactivity.py
index 74fbde8..761191a 100755
--- a/mathactivity.py
+++ b/mathactivity.py
@@ -35,6 +35,12 @@ logging.basicConfig()
 
 # The global grid unit size, in pixels.  Objects will snap to multiples of this value.
 GRID_SIZE = 50
+GRID_VISIBLE = False
+RADIAL_GRID_SIZE = math.pi/4
+
+# Width and height of region within which we can drag objects.
+DRAGGING_RECT_WIDTH = 16 * GRID_SIZE
+DRAGGING_RECT_HEIGHT = 16 * GRID_SIZE
 
 # The global grid angle size, in radians.
 RADIAL_GRID_SIZE = math.pi/8
@@ -192,6 +198,7 @@ class SymbolObject(Object):
         Object.__init__(self)
 
         self.pos = pos
+        self.last_pos = self.pos
         self.symbol = symbol
         
         self.angle = 0
@@ -242,7 +249,9 @@ class ShapeObject(Object):
         self.color = color
         self.points = points
         self.pos = pos
+        self.last_pos = self.pos
         self.angle = angle
+        self.last_angle = self.angle
         self.symbol = symbol
         self.area = 0
         self.centroid = Vector(0, 0)
@@ -327,7 +336,7 @@ class ShapeObject(Object):
         y_bearing = -16
         cr.move_to(self.pos.x - x_bearing, self.pos.y - y_bearing)
         cr.show_text(text)
-  
+
     # Algorithm to test whether point is inside any polygon
     def contains_point(self, pos):
         n = 0
@@ -385,6 +394,8 @@ class ObjectArea(gtk.Layout):
 
         # Set up drawing events.
         self.modify_bg(gtk.STATE_NORMAL, self.get_colormap().alloc_color('#ffffff'))
+        if GRID_VISIBLE:
+            self.connect('expose-event', self.expose_grid)
         self.connect('expose-event', self.expose_cb)
         
         # Capture the last drag coordinates      
@@ -395,6 +406,12 @@ class ObjectArea(gtk.Layout):
         self.objects.append(obj)
         self.queue_draw()
     
+    def add_shape_object(self, obj):
+        self.objects.append(obj)
+        self.queue_draw()
+        # Make sure the shape is placed correctly on the grid.
+        self.snap_object_to_grid(obj)
+    
     def clear_selection(self):
         if self.selected_object:
             self.selected_object.selected = False
@@ -416,26 +433,51 @@ class ObjectArea(gtk.Layout):
         self.queue_draw()
 
     def move_object(self, object, pos):
-        # Constrain on screen (don't want kids losing their boxes).
-        rect = self.get_allocation()
-        
-        x = max(object.width/2, min(pos.x, rect.width - object.width/2))
-        y = max(object.height/2, min(pos.y, rect.height - object.height/2))
-        
+        x, y = pos.x, pos.y
+         
+        # Tentatively place in the object in the new position
         object.pos = Vector(x, y)
-        
+
+        # Check whether any point of the object is outside the screen
+        for i in range (0, len(object.points) ):
+            p1 = object.points[i]
+            p1 = object.transform_point(p1)
+             
+            if p1.x < -1 or p1.x > DRAGGING_RECT_WIDTH or p1.y < -1 or p1.y > DRAGGING_RECT_HEIGHT:
+                # If any point is outside, move object back to last position.
+                object.pos = object.last_pos
+            
         self.queue_draw()
+                
+    def rotate_object(self, object, delta):
+        angle = delta
 
+        # Tentatively rotate the object to the new angle
+        object.angle = object.angle + angle
+        
+        # Check whether any point of the object is outside the screen
+        for i in range (0, len(object.points) ):
+            p1 = object.points[i]
+            p1 = object.transform_point(p1)
+             
+            if p1.x < -1 or p1.x > DRAGGING_RECT_WIDTH or p1.y < -1 or p1.y > DRAGGING_RECT_HEIGHT:
+                # If any point is outside, move object back to last position.
+                object.angle = object.last_angle
+        
+        self.queue_draw()
+           
     def snap_object_to_grid(self, object):
         x, y = object.pos.x, object.pos.y
         angle = object.angle
         
-        # Snap to grid.
+        # Snap position to grid.
         x = int((x + GRID_SIZE/2 + 1)/ GRID_SIZE) * GRID_SIZE
         y = int((y + GRID_SIZE/2 + 1)/ GRID_SIZE) * GRID_SIZE
         
-        angle = (int((angle)/ RADIAL_GRID_SIZE) * RADIAL_GRID_SIZE) % (2 * math.pi)
-        
+        # Snap angle to "radial grid"
+        # TODO: Test to see if this can be improved.
+        angle = (int((angle + RADIAL_GRID_SIZE/2)/ RADIAL_GRID_SIZE) * RADIAL_GRID_SIZE) % (2 * math.pi)
+         
         object.pos = Vector(x, y)
         object.angle = angle
         
@@ -444,17 +486,9 @@ class ObjectArea(gtk.Layout):
         
         self.queue_draw()
         
-    def rotate_object(self, object, delta):
-        angle = delta
-
-        object.angle = object.angle + angle
-        
-        self.queue_draw()
-
     def move_object_rel(self, object, delta):
-        self.move_object(object, 
-            Vector(object.pos.x + delta.x, object.pos.y + delta.y))
-
+        self.move_object(object, object.pos + delta)
+     
     def on_mouse(self, widget, event):
         epos = Vector(event.x, event.y)
         
@@ -464,12 +498,15 @@ class ObjectArea(gtk.Layout):
             if event.type == gtk.gdk.MOTION_NOTIFY:
                 # Rotate while dragging if option key is pressed                 
                 if event.state & MOD1_MASK:
+                    # Save the previous angle in case we have to undo the rotation.
+                    self.selected_object.last_angle = self.selected_object.angle
                     self.rotate_object(self.drag_object,
                         math.atan2(epos.y - self.drag_object.pos.y,
                                    epos.x - self.drag_object.pos.x) -
                         math.atan2(self.y_drag - self.drag_object.pos.y,
                                    self.x_drag - self.drag_object.pos.x))
                 else:
+                    self.selected_object.last_pos = self.selected_object.pos
                     self.move_object(self.drag_object, epos - self.drag_offset)
                     
             elif event.type == gtk.gdk.BUTTON_RELEASE:
@@ -547,33 +584,57 @@ class ObjectArea(gtk.Layout):
             if self.selected_object:
                 # Rotate if option key is pressed.
                 if event.state & MOD1_MASK:
-                    self.rotate_object(self.selected_object, -math.pi/8)
+                    # Save the previous angle in case we have to undo the rotation.
+                    self.selected_object.last_angle = self.selected_object.angle
+                    self.rotate_object(self.selected_object, -RADIAL_GRID_SIZE)       
                 else:
+                    # Save the previous position in case we have to undo the move.
+                    self.selected_object.last_pos = self.selected_object.pos
+                    # Move the object.
                     self.move_object_rel(self.selected_object, Vector(0, -GRID_SIZE))
+                    
             return True
 
         if key_name == 'Down':
             if self.selected_object:
                 if event.state & MOD1_MASK:
-                    self.rotate_object(self.selected_object, math.pi/8)
+                    # Save the previous angle in case we have to undo the rotation.
+                    self.selected_object.last_angle = self.selected_object.angle
+                    self.rotate_object(self.selected_object, RADIAL_GRID_SIZE) 
                 else:
+                    # Save the previous position in case we have to undo the move.
+                    self.selected_object.last_pos = self.selected_object.pos
+                    # Move the object.
                     self.move_object_rel(self.selected_object, Vector(0, GRID_SIZE))
+                    
             return True
 
         if key_name == 'Left':
             if self.selected_object:
                 if event.state & MOD1_MASK:
-                    self.rotate_object(self.selected_object, -math.pi/8)
+                    # Save the previous angle in case we have to undo the rotation.
+                    self.selected_object.last_angle = self.selected_object.angle
+                    self.rotate_object(self.selected_object, -RADIAL_GRID_SIZE)
                 else:
+                    # Save the previous position in case we have to undo the move.
+                    self.selected_object.last_pos = self.selected_object.pos
+                    # Move the object.
                     self.move_object_rel(self.selected_object, Vector(-GRID_SIZE, 0))
+                    
             return True
 
         if key_name == 'Right':
             if self.selected_object:
                 if event.state & MOD1_MASK:
-                    self.rotate_object(self.selected_object, math.pi/8)
+                    # Save the previous angle in case we have to undo the rotation.
+                    self.selected_object.last_angle = self.selected_object.angle
+                    self.rotate_object(self.selected_object, RADIAL_GRID_SIZE)
                 else:
+                    # Save the previous position in case we have to undo the move.
+                    self.selected_object.last_pos = self.selected_object.pos
+                    # Move the object.
                     self.move_object_rel(self.selected_object, Vector(GRID_SIZE, 0))
+                    
             return True
 
     def expose_cb(self, widget, event):
@@ -581,12 +642,42 @@ class ObjectArea(gtk.Layout):
 
         cr.rectangle(event.area.x, event.area.y, event.area.width, event.area.height)
         cr.clip()
-
+         
         # Draw in reverse order, so that first in the list is drawn on top.
         for o in reversed(self.objects):
             cr.save()
             o.draw(cr)
             cr.restore()
+             
+    def expose_grid(self, widget, event):
+        cr = self.bin_window.cairo_create()
+        
+        cr.rectangle(event.area.x, event.area.y, event.area.width, event.area.height)
+        cr.clip()
+        
+        cr.save()
+        self.draw(cr)
+        cr.restore()
+            
+    def draw(self, cr):
+        # Draw the grid.
+        cr.set_source_rgb(0, 0, 0)
+        cr.set_line_width(1.0)
+        
+        #rect = self.get_allocation()
+        
+        # Draw the horizontal lines.
+        for i in range(DRAGGING_RECT_HEIGHT/GRID_SIZE + 1):
+            cr.move_to(0, i * GRID_SIZE)
+            cr.line_to(int(DRAGGING_RECT_WIDTH/GRID_SIZE) * GRID_SIZE, i * GRID_SIZE)
+
+        # Draw the vertical lines.
+        for i in range(DRAGGING_RECT_WIDTH/GRID_SIZE + 1):
+            cr.move_to(i * GRID_SIZE, 0)
+            cr.line_to(i * GRID_SIZE, int(DRAGGING_RECT_HEIGHT/GRID_SIZE) * GRID_SIZE)
+            
+        cr.stroke()
+            
 
 class ObjectTestScreen(ObjectArea):
     """Empty screen containing a variety of test objects to interact with."""
@@ -597,18 +688,25 @@ class ObjectTestScreen(ObjectArea):
         self.add_test_objects()
 
     def add_test_objects(self):
-        SQUARE_SHAPE = [ Vector(0, 0), Vector(250, 0), Vector(250, 250), Vector(0, 250) ]
-        TRIANGLE_SHAPE = [ Vector(0, 0), Vector(250, 0), Vector(0, -250) ]
-        TRAPEZOID_SHAPE = [ Vector(0, 0), Vector(350, 0), Vector(150, -200), Vector(0, -200) ]
-
-        #self.add_object(ShapeObject(Color.BLUE, "A", SQUARE_SHAPE, (200, 200), 0))
-        #self.add_object(ShapeObject(Color.RED, "B", SQUARE_SHAPE, (550, 400), math.pi/8))
+        SQUARE_SHAPE = ( Vector(0, 0), Vector(250, 0), Vector(250, 250), Vector(0, 250) )
+        LARGE_SQUARE_SHAPE = ( Vector(0, 0), Vector(300, 0), Vector(300, 300), Vector(0, 300) )
+        TRIANGLE_SHAPE = ( Vector(0, 0), Vector(250, 0), Vector(0, -250) )
+        TRAPEZOID_SHAPE = ( Vector(0, 0), Vector(350, 0), Vector(150, -200), Vector(0, -200))
+        
+        problem_number = 0
+        
+        if problem_number == 0:       
+            self.add_object(ShapeObject(Color.BLUE, "A", SQUARE_SHAPE, Vector(200, 200), 0))
+            self.add_object(ShapeObject(Color.RED, "B", LARGE_SQUARE_SHAPE, Vector(550, 400), math.pi/4))         
+        elif problem_number == 1:
+            self.add_object(ShapeObject(Color.BLUE, "A", SQUARE_SHAPE, Vector(200, 200), math.pi/4))
+            self.add_object(ShapeObject(Color.RED, "B", SQUARE_SHAPE, Vector(550, 400), 0))
         
-        #self.add_object(ShapeObject(Color.GREEN, "A", TRIANGLE_SHAPE, (200, 200), 0))
-        #self.add_object(ShapeObject(Color.BLUE, "B",TRIANGLE_SHAPE, (500, 600), -math.pi/4))
+        #self.add_object(ShapeObject(Color.GREEN, "A", TRIANGLE_SHAPE, Vector(200, 200), 0))
+        #self.add_object(ShapeObject(Color.BLUE, "B",TRIANGLE_SHAPE, Vector(500, 600), -math.pi/4))
 
-        self.add_object(ShapeObject(Color.GREEN, "A", TRAPEZOID_SHAPE, Vector(200, 200), 0))
-        self.add_object(ShapeObject(Color.RED, "B", TRAPEZOID_SHAPE, Vector(500, 600), -math.pi/4))
+        #self.add_shape_object(ShapeObject(Color.GREEN, "A", TRAPEZOID_SHAPE, Vector(238, 207), 0))
+        #self.add_shape_object(ShapeObject(Color.RED, "B",TRAPEZOID_SHAPE, Vector(498, 613), -math.pi/4))
 
         #self.add_object(LineSegmentObject((800, 100), 200))
         #self.add_object(LineSegmentObject((900, 100), 300))