sketch shows how to do basic vector math

Author: m9dfukc

sketches/vector_studies/vector_studies.pde

@@ -0,0 +1,34 @@
+PVector[] wings = new PVector[900];
+
+void setup() {
+  size(700, 700);
+  int index = 0;
+  
+  for (int y = 0; y < 30; y++) {
+    for (int x = 0; x < 30; x++) {
+      float posX = map(x, 0, 29, 100, width - 100);
+      float posY = map(y, 0, 29, 100, height - 100);
+      
+      wings[index] = new PVector(posX, posY);
+      index = index + 1;
+    }
+  }
+}
+
+void draw() {
+  background(255);
+  PVector look = new PVector(mouseX, mouseY);
+  for (int i=0; i < wings.length; i++) {
+    PVector start = wings[i];
+    PVector end   = new PVector(start.x, start.y + 20);
+    
+    PVector t = PVector.sub(look, start);
+    float rotation = t.heading2D();
+    
+    PVector v = PVector.sub(end, start);
+    v.rotate(rotation + PI / 2.0);
+    PVector newEnd = PVector.sub(start, v);
+    
+    line(start.x, start.y, newEnd.x, newEnd.y);
+  }
+}