Mesh is a way of making different projects interact - even if they're on different computers. Meshed Scratch projects are capable of two basic features: variables and broadcasts.

How to get MeshEdit

Mesh is available in two main ways:

Mesh by BYOB external applicationEdit

Download Jens's Build Your Own Blocks - it comes with Mesh, easily available.

Mesh by Modification of the Scratch InterfaceEdit

This requires editing of the System Browser.

To do so, the following steps must be taken:

  • Shift-click the R in the Scratch logo.
  • Select "turn fill screen off".
  • A white area at the bottom and right side of the screen will appear. Click on the white area and select "open...".
  • Select "browser".
  • The System Browser will open. Select Scratch-UI-Panes - ScratchFrameMorph - menu/button actions - addServerCommandsTo: .
  • Edit the "t2 ← true" text in the code and change it to "t2 ← false".
  • Right-click and select "accept".
  • Enter in your initials and click "accept".
  • Exit the System Browser.

After one of the listed methods has been completed, Mesh is then available on the Scratch program. To save Mesh (leaving the edits), turn the fill screen back on and Shift-Click the R yet again, this time clicking "Save image for end-user". Mesh is now saved on your Scratch program.

  • If mesh has been saved but is not wanted anymore, the 'false' statement in the System Browser must be changed back to 'true'.

This method was first discovered by a Scratch user called MathWizz.

How to host and join Mesh sessionsEdit

Host Mesh and Join Mesh

Shift-clicking the Share button with Mesh enabled lets you host and join Mesh sessions.

A Scratch program that has Mesh available on it looks like the un-edited Scratch program. However, shift-clicking Share will reveal two new buttons: Host Mesh and Join Mesh.
  • Host Mesh begins a mesh session.
  • Join Mesh allows you to join a session.

To host mesh:

  • Select Host Mesh.
  • The hosting computer's IP address will be shown.

To join a Mesh session:

  • Select Join Mesh.
  • Enter in the IP address of the computer that is hosting the Mesh session.

If the host does not reveal the IP address and has forgotten it, he/she can shift-click the Share button and select Show IP address. It will show the numbers, and they can be sent to the joining computer.

A mesh session can contain more than two connectors

How to program with Mesh's featuresEdit

Programming with mesh is the same as without - the interface is the same as always. But when a mesh session is in activity, it changes:

  • Broadcasts are received on all Scratch connectors.
  • All variables are open to the connectors.

If a broadcast is created on one program, it strangely does not exist on the other. To create a broadcast for use of all connectors, it has to be made on each computer - programming in mesh is best done outside a session. The same applies to variables.

To read variables from another computer, the ([slider] sensor value) block must be used. Variables are shown in the drop-down menu, and can be selected from there.

To test it, the following instructions are to be used:

  • On one Scratch program, show the ([slider] sensor value) block.
  • Select the drop-down box and look.
  • All variables are in the list.
  • To read a variable, use the described block.

External linksEdit