float angle=0;
void setup() {
size(300, 300);
noStroke();
smooth();
}

void drawTriangles(float x, float y) {
  fill(0);
  triangle(x, y, x+40,y+40,x-20,y+40);
  triangle(x+60, y, x+90,y+40,x+50,y+40);
  triangle(x+20, y+70, x+60,y+110,x+10,y+110);
}

void draw() {
  background(255);
  float x = 50+cos(angle)*30;
  float y = mouseY;
  drawTriangles(x,y);
  angle += 0.03;
}