Realistic small fish movement

3 files changed, 41 insertions, 24 deletions

diff --git a/bridge.py b/bridge.py
index 757d3c6..b7e4576 100644
--- a/bridge.py
+++ b/bridge.py
@@ -11,8 +11,8 @@ else:
     have_lumiversepython = True
 
 class Bridge(object):
-    WIDTH = constants.BRIDGE_WIDTH
-    HEIGHT = constants.BRIDGE_HEIGHT
+    WIDTH = BRIDGE_WIDTH
+    HEIGHT = BRIDGE_HEIGHT
 
     def __init__(self):
         if have_lumiversepython:
diff --git a/color.py b/color.py
index 058abb4..c65252b 100644
--- a/color.py
+++ b/color.py
@@ -7,7 +7,7 @@ class Vector(object):
     __slots__ = ('x', 'y', 'z')
 
     """3-dimensional vector class."""
-    def __init__(self, x, y, z):
+    def __init__(self, x=0, y=0, z=0):
         """Create a vector from its components."""
         self.x = x
         self.y = y
@@ -40,6 +40,17 @@ class Vector(object):
     def __eq__(self, other):
         return self.x == other.x and self.y == other.y and self.z == other.z
 
+    def unit(self):
+        return self / abs(self)
+
+    def rot2d(self, theta):
+        costheta = math.cos(theta)
+        sintheta = math.sin(theta)
+        new_x = self.x * costheta - self.y * sintheta
+        new_y = self.x * sintheta + self.y * costheta
+        return self.__class__(new_x, new_y)
+
+
     @property
     def components(self):
         return (self.x, self.y, self.z)
diff --git a/fish_show.py b/fish_show.py
index f3ccf25..7cd8300 100644
--- a/fish_show.py
+++ b/fish_show.py
@@ -1,5 +1,6 @@
 from __future__ import division
 import color
+from color import Vector
 import random
 import constants
 from constants import *
@@ -18,20 +19,23 @@ class Fish(object):
         self.speed = step
         self.step = step
 
-        self.speed = Vector(10, 0)
-        self.drag = -1
+        self.speed = Vector(0.1, 0)
+        self.drag = -0.09
 
-        self.tailAcceleration = color.Vector(5, 0)
+        self.tailAccelMag = 0.4
+        self.tailAcceleration = Vector(self.tailAccelMag, 0)
         self.tailDuration = 2
         self.tailMoving = False
-        self.tailThreshold = 5
+        self.tailThreshold = 0.7
         self.tailMoveCount = 0
 
     def update(self):
         """Swim gently to the other side of the bridge."""
-        self.speed += self.drag * self.speed / abs(self.speed)
+        self.speed += self.drag * self.speed
         if abs(self.speed) < self.tailThreshold:
             self.tailMoving = True
+            self.tailThreshold = rand_in_range(0.5, 1.4)
+            self.fix_direction()
         if self.tailMoveCount > self.tailDuration:
             self.tailMoveCount = 0
             self.tailMoving = False
@@ -47,22 +51,21 @@ class Fish(object):
             self.x = -self.width
         if self.x < -self.width:
             self.x = constants.BRIDGE_WIDTH
-        if self.y < -self.width:
-            self.y = constants.BRIDGE_HEIGHT + self.height
-        if self.y > -self.height:
-            self.y = constants.BRIDGE_HEIGHT
 
-    def fix_direction(self, theta=None):
-        if theta is None:
-            theta = random.random * math.pi / 2 - math.pi / 4
-        costheta = math.cos(theta)
-        sintheta = math.sin(theta)
-        speedx = self.tailAcceleration.components[0]
-        speedy = self.tailAcceleration.components[1]
-        data.tailAcceleration = color.Vector(
-            speedx * costheta - speedy * sintheta,
-            speedx * sintheta + speedy * costheta
-        )
+        print(self.x, self.y)
+
+    def fix_direction(self):
+        min_theta = -0.32
+        max_theta = 0.32
+        if self.y < 0:
+            min_theta = 0
+        if self.y > 1:
+            max_theta = 0
+            
+        #theta = rand_in_range(min_theta, max_theta)
+        theta = random.gauss((max_theta+min_theta)/2, (max_theta - min_theta)/12)
+        self.tailAcceleration = Vector(self.tailAccelMag, 0).rot2d(theta)
+        
 
 class Light(object):
     """Represent a bridge light and its state."""
@@ -144,10 +147,13 @@ class FishShow(Show):
         self.lights = [Light(x, y, self.bridge.get_light(x, y))
                        for y in xrange(self.bridge.HEIGHT)
                        for x in xrange(self.bridge.WIDTH)]
-        self.fish = Fish(0, 0, 23, 1.5, color.black, 1)
+        self.fish = Fish(0, 0.5, 23, 1.5, color.black, 1)
 
 
     def update(self):
         self.fish.update()
         for light in self.lights:
             light.update(self.fish)
+
+def rand_in_range(low, high):
+    return random.random() * (high - low) + low