Bigcanvas is an infinite online canvas that you can draw on.

Picture yourself, sitting at your computer. Pull the camera backwards, revealing your house, your street, your city. Zoom out further: your country, a continent, oceans, until we have all of planet Earth in view.

But we don't stop there. Zoom out further to reveal a vast expanse of nothing for a while, until planets appear, and the Sun. Everything ever made by humankind is contained in this frame.

But we still don't stop. We keep zooming out until our entire solar system is nothing but a dot. Other stars appear, dozens, thousands, millions, billions. The structure of the Milky Way is revealed. We continue until that, too, is nothing but a speck. As we expand our horizon even further, billions upon billions of other galaxies become visible.

We are now looking at the vast expanse of the entire observable universe. Pretty big, but not quite … infinite.

This canvas is.

And you're invited to draw on it.

• Drag the canvas with the left mouse buttonyour finger to look around
• When you are ready to start drawing, clicktap draw at the top
• Drag with the left mouse buttonyour finger across the screen to draw

Drawing

ClickTap draw at the top or press 2. Drag the left mouse buttonyour finger to draw. Sorry, multi-touch is not yet supported.

Moving around

ClickTap move at the top or press 1. Drag the left mouse buttonyour finger to move around.

You can also press and drag the middle mouse button (mouse wheel) to scroll, even when draw is active. Instead of holding the middle button, you can also hold space bar and use the left mouse button.

You can also scroll using the keyboard:

• ← → ↑ ↓
• ASDW
• OEU. (for dvorak keyboards)

Zooming

Use the mouse wheel to zoom.

Jumping

The links at the top left jump to random places:

• empty jumps to a random place in a square of roughly 650 m × 650 m, ideal for finding an empty space for your own artwork.
• random jumps to a random place where someone has drawn something before.

About

Bigcanvas is both an art project and an experiment with modern web technologies. On the client side, it uses HTML5 features like canvas and WebSockets. On the server side, it uses the Go language.

Bigcanvas was written as a weekend project by Thomas ten Cate (Frozen Fractal).

Is it really infinite?

To within machine limits, yes. A size of 2³² pixels on a 80 ppi monitor would only get us a canvas the size of the moon. With 2⁶⁴ pixels we could span nearly a lightyear. But Bigcanvas uses arbitrary-size integers, encoded in base 64, to represent coordinates. Practical limitations on filename length and URL length mean that the actual size is probably somewhere around 10²⁶⁶ metres, which is still vastly more than the meagre 10²⁴ metres of the visible universe.

Why is there no eraser?

"We don't make mistakes, just happy little accidents." —Bob Ross

How does it work?

For technical details, see this blog post.