190328a

2019/sketch_190328a/sketch_190328a.pyde

@@ -0,0 +1,52 @@
+#from forms import var_bar
+
+def setup():
+    size(500, 500)
+    
+def draw():
+    background(200)
+
+    a = PVector(200, 250)
+    b = PVector(mouseX, mouseY)
+    c = (a + b) / 2
+    ra, rb = 75, 25
+    
+    noFill()
+    strokeWeight(1)
+    stroke(0)
+    ellipse(b.x, b.y, rb*2, rb*2)
+    ellipse(a.x, a.y, ra*2, ra*2)
+    ellipse(c.x, c.y, ra+rb, ra+rb)
+    line(a.x, a.y, b.x, b.y)
+    
+    strokeWeight(4)
+    circ_circ_tangent(b, a, rb, ra)
+
+
+    
+def circ_circ_tangent(p1, p2, r1, r2):
+    d = dist(p1.x, p1.y, p2.x, p2.y)    
+    ri = r1 - r2
+    if d > abs(ri):
+        line_angle = atan2(p1.x - p2.x, p2.y - p1.y)
+        theta = asin(ri / float(d))
+        stroke(0)
+        
+        x1 = cos(line_angle - theta) * r1
+        y1 = sin(line_angle - theta) * r1
+        x2 = cos(line_angle - theta) * r2
+        y2 = sin(line_angle - theta) * r2
+        line(p1.x - x1, p1.y - y1, p2.x - x2, p2.y - y2)
+
+        x1 = -cos(line_angle + theta) * r1
+        y1 = -sin(line_angle + theta) * r1
+        x2 = -cos(line_angle + theta) * r2
+        y2 = -sin(line_angle + theta) * r2
+        line(p1.x - x1, p1.y - y1, p2.x - x2, p2.y - y2)   
+        stroke(0, 255, 0)  
+        
+        arc(p1.x, p1.y, r1 * 2, r1 * 2,
+                PI + line_angle - theta,  line_angle + TWO_PI + theta)     
+        stroke(255, 0, 0)
+        arc(p2.x, p2.y,r2 * 2, r2 * 2,
+                line_angle + theta,  line_angle + PI - theta)