Added new P3D examples

java/libraries/opengl/examples/Form/Toroid/Toroid.pde

@@ -0,0 +1,182 @@
+/**
+ * Interactive Toroid
+ * by Ira Greenberg. 
+ * 
+ * Illustrates the geometric relationship between Toroid, Sphere, and Helix
+ * 3D primitives, as well as lathing principal.
+ * 
+ * Instructions: <br />
+ * UP arrow key pts++ <br />
+ * DOWN arrow key pts-- <br />
+ * LEFT arrow key segments-- <br />
+ * RIGHT arrow key segments++ <br />
+ * 'a' key toroid radius-- <br />
+ * 's' key toroid radius++ <br />
+ * 'z' key initial polygon radius-- <br />
+ * 'x' key initial polygon radius++ <br />
+ * 'w' key toggle wireframe/solid shading <br />
+ * 'h' key toggle sphere/helix <br />
+ */
+
+int pts = 40; 
+float angle = 0;
+float radius = 60.0;
+
+// lathe segments
+int segments = 60;
+float latheAngle = 0;
+float latheRadius = 100.0;
+
+//vertices
+PVector vertices[], vertices2[];
+
+// for shaded or wireframe rendering 
+boolean isWireFrame = false;
+
+// for optional helix
+boolean isHelix = false;
+float helixOffset = 5.0;
+
+void setup(){
+  size(640, 360, P3D);
+}
+
+void draw(){
+  background(50, 64, 42);
+  // basic lighting setup
+  lights();
+  // 2 rendering styles
+  // wireframe or solid
+  if (isWireFrame){
+    stroke(255, 255, 150);
+    noFill();
+  } 
+  else {
+    noStroke();
+    fill(150, 195, 125);
+  }
+  //center and spin toroid
+  translate(width/2, height/2, -100);
+
+  rotateX(frameCount*PI/150);
+  rotateY(frameCount*PI/170);
+  rotateZ(frameCount*PI/90);
+
+  // initialize point arrays
+  vertices = new PVector[pts+1];
+  vertices2 = new PVector[pts+1];
+
+  // fill arrays
+  for(int i=0; i<=pts; i++){
+    vertices[i] = new PVector();
+    vertices2[i] = new PVector();
+    vertices[i].x = latheRadius + sin(radians(angle))*radius;
+    if (isHelix){
+      vertices[i].z = cos(radians(angle))*radius-(helixOffset* 
+        segments)/2;
+    } 
+    else{
+      vertices[i].z = cos(radians(angle))*radius;
+    }
+    angle+=360.0/pts;
+  }
+
+  // draw toroid
+  latheAngle = 0;
+  for(int i=0; i<=segments; i++){
+    beginShape(QUAD_STRIP);
+    for(int j=0; j<=pts; j++){
+      if (i>0){
+        vertex(vertices2[j].x, vertices2[j].y, vertices2[j].z);
+      }
+      vertices2[j].x = cos(radians(latheAngle))*vertices[j].x;
+      vertices2[j].y = sin(radians(latheAngle))*vertices[j].x;
+      vertices2[j].z = vertices[j].z;
+      // optional helix offset
+      if (isHelix){
+        vertices[j].z+=helixOffset;
+      } 
+      vertex(vertices2[j].x, vertices2[j].y, vertices2[j].z);
+    }
+    // create extra rotation for helix
+    if (isHelix){
+      latheAngle+=720.0/segments;
+    } 
+    else {
+      latheAngle+=360.0/segments;
+    }
+    endShape();
+  }
+}
+
+/*
+ left/right arrow keys control ellipse detail
+ up/down arrow keys control segment detail.
+ 'a','s' keys control lathe radius
+ 'z','x' keys control ellipse radius
+ 'w' key toggles between wireframe and solid
+ 'h' key toggles between toroid and helix
+ */
+void keyPressed(){
+  if(key == CODED) { 
+    // pts
+    if (keyCode == UP) { 
+      if (pts<40){
+        pts++;
+      } 
+    } 
+    else if (keyCode == DOWN) { 
+      if (pts>3){
+        pts--;
+      }
+    } 
+    // extrusion length
+    if (keyCode == LEFT) { 
+      if (segments>3){
+        segments--; 
+      }
+    } 
+    else if (keyCode == RIGHT) { 
+      if (segments<80){
+        segments++; 
+      }
+    } 
+  }
+  // lathe radius
+  if (key =='a'){
+    if (latheRadius>0){
+      latheRadius--; 
+    }
+  } 
+  else if (key == 's'){
+    latheRadius++; 
+  }
+  // ellipse radius
+  if (key =='z'){
+    if (radius>10){
+      radius--;
+    }
+  } 
+  else if (key == 'x'){
+    radius++;
+  }
+  // wireframe
+  if (key =='w'){
+    if (isWireFrame){
+      isWireFrame=false;
+    } 
+    else {
+      isWireFrame=true;
+    }
+  }
+  // helix
+  if (key =='h'){
+    if (isHelix){
+      isHelix=false;
+    } 
+    else {
+      isHelix=true;
+    }
+  }
+}
+