class LineElement {
int x, y, x2, y2;
}
ArrayList<LineElement> lines = new ArrayList<LineElement>();
int p_x = -1, p_y = -1;
void setup() {
size(320,
200);
stroke(255);
strokeWeight(2);
}
void draw() {
background(0);
stroke(255);
for(LineElement l : lines) {
line(l.x, l.y, l.x2, l.y2);
}
stroke(0,
0, 255);
if(p_x >= 0 && p_y >= 0) {
line(p_x, p_y, mouseX, mouseY);
}
}
void mousePressed() {
if(p_x >= 0 && p_y >= 0) {
LineElement l = new LineElement();
l.x = p_x;
l.y = p_y;
l.x2 = mouseX;
l.y2 = mouseY;
lines.add(l);
}
p_x = mouseX;
p_y = mouseY;
}
