3D trail Effect

Programming Questions

joemilsom

in Programming Questions • 2 years ago

Hey,

I'm fairly new to processing and I just need some help trying to get a 3D trail effect working.

I can do this in a 2D space by simply using:

fill(0, 10);

rect(0, 0, width, height);

But when I try to do it in a 3D space it seems to separate the 2D and 3D elements from each other, so the rectangle fades in the background but the sphere is redrawn across the screen.

Can anyone offer me any tips as to how I would achieve a trail effect with a sphere?

Thanks.

Replies(3)

tfguy44

Re: 3D trail Effect

2 years ago

This works in 2D because the previous frame that's drawn remains, but becomes slightly darker.

This same method won't work in 3D.

What you should do instead is remember where the last spheres you drew were (for several previous frames), and redrawn them each time getting slightly darker (or more transparent).

In short, the 2D method you're using won't "scale up" to 3D. Try working with this instead:

/**
* ArrayList of objects
* by Daniel Shiffman.
* Edited by TfGuy44 for example purposes.
*
* This example demonstrates how to use a Java ArrayList to store
* a variable number of objects. Items can be added and removed
* from the ArrayList.
*
* Click and drag to add a trail of circles.
*/
ArrayList balls;
int ballWidth = 48;
void setup() {
size(200, 200);
smooth();
noStroke();
// Create an empty ArrayList
balls = new ArrayList();
// Start by adding one element
balls.add(new Ball(width/2, 0, ballWidth));
}
void draw() {
background(255);
// With an array, we say balls.length, with an ArrayList, we say balls.size()
// The length of an ArrayList is dynamic
// Notice how we are looping through the ArrayList backwards
// This is because we are deleting elements from the list
for (int i = balls.size()-1; i >= 0; i--) {
// An ArrayList doesn't know what it is storing so we have to cast the object coming out
Ball ball = (Ball) balls.get(i);
ball.move();
ball.display();
if (ball.finished()) {
// Items can be deleted with remove()
balls.remove(i);
}
}
}
void mouseMoved() {
// A new ball object is added to the ArrayList (by default to the end)
if( mousePressed){
balls.add(new Ball(mouseX, mouseY, ballWidth));
}
}

ignivome

Re: 3D trail Effect

2 years ago

I made a little sketch inspired from flight 404's Particle Emitters technique:

http://openprocessing.org/visuals/?visualID=40052

joemilsom

Re: 3D trail Effect

2 years ago

Thanks!!

This will help me out a lot in trying to get some decent looking stuff in 3D.

Top Reply

3D trail Effect

Replies(3)

Re: 3D trail Effect

Re: 3D trail Effect

Re: 3D trail Effect

Statistics

Tags

Actions

Related Posts