Hi guys why my text doesn't show?

Processing Coding Questions
14

Regarding the initial moving-along-a-path question, one general approach is a list-based interpolation.

Here is an example. In setup, a path made of points is defined. In draw, the current path location is computed based on the clock. Then that location (0-1) is passed to the lerpVectors function to find the current point along the path.

// LerpVectorsSimplified
// 2019-04 Processing 3.4 - based on LerpVectorsExample by Jeremy Douglass
PVector vecs[];
PVector loc;

void setup() {
  size(200, 200);
  // mark path points
  vecs = new PVector[4];
  vecs[0] = new PVector(10, 10);
  vecs[1] = new PVector(width-10, 10);
  vecs[2] = new PVector(width-10, height-10);
  vecs[3] = new PVector(10, height-10);
  stroke(255,0,0);
  fill(0,0,255);
} 
 
void draw() {
  background(255);
  int time = millis()%4000;  // a clock that counts up to 4000 and starts over
  float sawtoothWave = map(time, 0, 3999, -1, 1);  // from -1 to 1, then starts over
  float triangleWave = abs(sawtoothWave);  // bounces 0-1-0-1-0
  loc = lerpVectors(triangleWave, vecs);  // find our location in 2D path based on 0-1
  ellipse(loc.x, loc.y, 50, 50);  // draw at the location
}
  
// based on an amount, find the location along a path made of points
PVector lerpVectors(float amt, PVector... vecs) {
  if(vecs.length==1){ return vecs[0]; }
  float cunit = 1.0/(vecs.length-1);
  return PVector.lerp(vecs[floor(amt / cunit)], vecs[ceil(amt / cunit)], amt%cunit/cunit);
}
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