@@ -0,0 +1,40 @@
+/**
+ * Perspective vs. Ortho
+ *
+ * Move the mouse left to right to change the "far" 
+ * parameter for the perspective() and ortho() functions.
+ * This parameter sets the maximum distance from the 
+ * origin away from the viewer and will clip the geometry.
+ * Click a mouse button to switch between the perspective and
+ * orthographic projections.
+ */
+
+
+boolean showPerspective = false;
+
+void setup() {
+  size(600, 360, P3D);
+  noFill();
+  fill(255);
+  noStroke();
+}
+
+void draw() {
+  lights();
+  background(0);
+  float far = map(mouseX, 0, width, 120, 400);
+  if (showPerspective == true) {
+    perspective(PI/3.0, float(width)/float(height), 10, far);
+  } else {
+    ortho(0, width, 0, height, 10, far);
+  }
+  translate(width/2, height/2, 0);
+  rotateX(-PI/6);
+  rotateY(PI/3);
+  box(180);
+}
+
+void mousePressed() {
+  showPerspective = !showPerspective;
+}
+