improve ShapeTransform.py

examples.py/3D/Form/ShapeTransform/ShapeTransform.py

@@ -1,86 +1,73 @@
 """
- * Shape Transform
- * by Ira Greenberg.    
- * 
- * Illustrates the geometric relationship 
- * between Cube, Pyramid, Cone and 
- * Cylinder 3D primitives.
- * 
- * Instructions:<br />
- * Up Arrow - increases points<br />
- * Down Arrow - decreases points<br />
- * 'p' key toggles between cube/pyramid<br />
- """
+  Shape Transform
+  by Ira Greenberg.
+  (Rewritten in Python by Jonathan Feinberg.)
+
+  Illustrates the geometric relationship
+  between Cube, Pyramid, Cone and
+  Cylinder 3D primitives.
 
-from processing.core import PVector
+  Instructions:
+  Up Arrow - increases points
+  Down Arrow - decreases points
+  'p' key toggles between cube/pyramid
+ """
 
-pts = 4 
+# constants
 radius = 99
 cylinderLength = 95
-isPyramid = False
 angleInc = PI / 300.0
 
+# globals that can be chaned by the user
+pts = 12
+isPyramid = False
+
 def setup():
     size(640, 360, P3D)
     noStroke()
-    
+
 def draw():
-    global cylinderLength
-
     background(170, 95, 95)
     lights()
     fill(255, 200, 200)
     translate(width / 2, height / 2)
     rotateX(frameCount * angleInc)
     rotateY(frameCount * angleInc)
     rotateZ(frameCount * angleInc)
-    # initialize vertex arrays
-    vertices = [[PVector() for x in range(pts+1)],
-                [PVector() for x in range(pts+1)]]
-    # fill arrays
-    for i in range(2):
-        angle = 0
-        for v in vertices[i]:
-            if isPyramid:
-                if i == 1:
-                    v.x = 0
-                    v.y = 0
-                else:
-                    v.x = cos(radians(angle)) * radius
-                    v.y = sin(radians(angle)) * radius
-            else:
-                v.x = cos(radians(angle)) * radius
-                v.y = sin(radians(angle)) * radius
-            v.z = cylinderLength 
-            # the .0 after the 360 is critical
-            angle += 360.0 / pts
-        cylinderLength *= -1
-
+
+    dTheta = TWO_PI / pts
+    x = lambda(j): cos(dTheta * j) * radius
+    y = lambda(j): sin(dTheta * j) * radius
+
     # draw cylinder tube
     beginShape(QUAD_STRIP)
-    for j in range(pts+1):
-        vertex(vertices[0][j].x, vertices[0][j].y, vertices[0][j].z)
-        vertex(vertices[1][j].x, vertices[1][j].y, vertices[1][j].z)
+    for j in range(pts + 1):
+        vertex(x(j), y(j), cylinderLength)
+        if isPyramid:
+            vertex(0, 0, -cylinderLength)
+        else:
+            vertex(x(j), y(j), -cylinderLength)
     endShape()
     #draw cylinder ends
-    for i in range(2):
+    beginShape()
+    for j in range(pts + 1):
+        vertex(x(j), y(j), cylinderLength)
+    endShape(CLOSE)
+    if not isPyramid:
         beginShape()
-        for v in vertices[i]:
-            vertex(v.x, v.y, v.z)
+        for j in range(pts + 1):
+            vertex(x(j), y(j), -cylinderLength)
         endShape(CLOSE)
-    
+
 """
  up/down arrow keys control
  polygon detail.
  """
 def keyPressed():
     global pts, isPyramid
-    print key
     if key == CODED:
-        # pts
         if keyCode == UP and pts < 90:
             pts += 1
-            print pts 
         elif keyCode == DOWN and pts > 4:
             pts -= 1
     elif key == ord('p'):