_

UI/Objects/nr_objects/dynamic_objects/Rope.py

@@ -0,0 +1,99 @@
+from numpy import array
+import pygame
+import math
+
+
+class Rope:
+
+    class Node:
+        def __init__(self, position):
+            self.position = position
+            self.previous_position = position
+            self.locked = False
+
+        def progress(self, gravity):
+            if self.locked is False:
+                position_before_update = self.position
+                self.position += self.position - self.previous_position
+                self.position[1] += gravity
+                self.previous_position = position_before_update
+
+    class Connection:
+        def __init__(self, a, b, length):
+            self.a = a
+            self.b = b
+            self.length = length
+
+        def balance(self):
+            center = (self.a.position + self.b.position) * 0.5
+            connection_vector = (self.b.position - self.a.position)
+            connection_vector /= math.sqrt(sum(connection_vector ** 2))
+            connection_vector *= self.length * 0.5
+
+            if self.b.locked is False:
+                self.b.position = center + connection_vector
+            if self.a.locked is False:
+                self.a.position = center - connection_vector
+
+    def __init__(self, position, length, nodes_n, nodes_r, rope_width, scene, gravity=1, start_angle=1,
+                 node_color=(255, 100, 100), rope_color=(255, 160, 160)):
+        self.position = position
+        self.length = length
+        self.nodes_n = nodes_n
+        self.nodes_r = nodes_r
+        self.rope_width = rope_width
+        self.gravity = gravity
+        self.start_angle = start_angle
+        self.scene = scene
+        self.node_color = node_color
+        self.rope_color = rope_color
+        self.pd_ = self.scene.pd_
+
+        self.initial_direction = array([math.cos(self.start_angle), math.sin(self.start_angle)])
+
+        self.rope_segment_length = self.length / (self.nodes_n - 1)
+        self.rescaled_rope_segment_length = self.rope_segment_length * self.pd_
+        self.rescaled_nodes_r = self.nodes_r * self.pd_
+        self.rescaled_rope_width = self.rope_width * self.scene.pd_
+
+        self.nodes = [self.Node(self.position +
+                                self.initial_direction * i * self.rescaled_rope_segment_length)
+                      for i in range(self.nodes_n)]
+
+        self.nodes[0].locked = True
+
+        self.connections = [self.Connection(self.nodes[i], self.nodes[i + 1], self.rescaled_rope_segment_length)
+                            for i in range(len(self.nodes) - 1)]
+
+    def progress(self):
+        for node in self.nodes:
+            node.progress(self.gravity)
+
+        for _ in range(6):
+            for connection in self.connections:
+                connection.balance()
+
+    def blit(self):
+        if self.pd_ != self.scene.pd_:
+            self.rescaled_rope_segment_length = self.rope_segment_length * self.pd_
+            self.rescaled_nodes_r = self.nodes_r * self.pd_
+            self.rescaled_rope_width = self.rope_width * self.pd_
+
+            for connection in self.connections:
+                connection.length = self.rescaled_rope_segment_length
+
+        for i in range(len(self.nodes) - 1):
+            pygame.draw.line(self.scene.s, self.rope_color,
+                             self.scene.matrix @ self.nodes[i].position,
+                             self.scene.matrix @ self.nodes[i + 1].position,
+                             int(self.rescaled_rope_width))
+
+        for node in self.nodes:
+            pygame.draw.circle(self.scene.s, self.node_color, self.scene.matrix @ node.position, self.rescaled_nodes_r)
+
+    @staticmethod
+    def to_ints(iterable):
+        for i in range(len(iterable)):
+            iterable[i] = int(iterable[i])
+
+        return iterable