Help Topics Version 2.0

Multiple Displays

Increasing the actual size of the space your content is presented on is a proven means to raise audience attention. This section was written to give you support when it comes to setting up multi-touch projects on multiple displays.

You can connect any number of Touch Players in a project. However, currently you can attach only up to six displays to a Mac Pro running Touch Player. This restriction doesn't come from the software, but from the Mac hardware. Whenever these technical specifications change, ~sedna is determined to adapt ~sedna touch to the new facts.


When synchronizing your project, consider that each connected Player will be sent the full project, even if the corresponding Player shows only part of the scenario. You have to make sure that any Mac running a Touch Player must have sufficient performance to cope with the task assigned to it.

As the complexity of projects grows, you may find that a Mac Mini won't provide the performance needed, even with just one display in use. With the playback of multiple high-res video clips encoded with different encoders, you are likely to see the playback on a Mac Mini suffer from a lack of performance. If multiple displays are required, you will need a Mac Pro anyway.


When it comes to multiple-display setups, please consider that exactly one multi-touch device per Player Mac can be used for user interaction. Note: This also applies to MultiTaction devices.

However, so called touch overlays as offered by PQ Labs and ZaagTech are a good way to increase the multi-touch area of a setup. These devices are hardware frames that are mounted on top of displays to detect touches even on displays that aren't touch-capable.

Touch overlays can be used in addition to the specified number of allowed displays on a Mac, i.e. on a Mac Mini you can use one display and one touch overlay, on a Mac Pro you can use up to six displays and one touch overlay. Technically, a touch overlay is considered an input device such as a mouse.

Content Synchronization

The next to consider is content synchronization with two aspects, the first one being content playback. The synchronization of content playback on a frame-to-frame basis is possible only on displays that are attached to the very same Mac.

Two displays that stand next to each other but are attached to different Macs are likely show to an ever growing time offset. Unfortunately, nothing can be done about that. If you plan for synchronized playback across displays, you have to use one Mac Pro with sufficient performance. Mac Minis can't be used as their performance is insufficient for multiple displays.

The other aspect concerning synchronization is user interaction. Imagine a project with two displays that stand next to each other. Just one of the displays can provide user interaction. If the displays are attached to different Macs, you can't interact with objects that are located on the other display.

Note: This also affects Actions and Scripts. Events or scripts on a component on Mac 1 cannot trigger actions on an object that is located on Mac 2.

Understanding Displays

It is essential that you understand what "display" means. As defined in ~sedna touch, displays are virtual views on the project's content. The next couple of images shall visualize this. The following image shows a project on the Stage of Touch Creator. It contains a Media Player with a playing video and two displays.

The following image shows the content as seen on Touch Players that use the left display.

The following image shows the content as seen on Touch Players that use the right display.

You can use any number of displays in Touch Creator without affecting the content of a project. Any Mac that gets synchronized by Touch Creator and refers to a display name as used in the project will get the complete project, but will only display the components seen within the referred displays.

Also, each of the connected Touch Players can have a multi-touch display or a touch overlay allowing users to interact with the components available on the referred display. However, if you interact with components on one Touch Player, the same component won't be affected on other Touch Players.

Last, but not least, you can use any display defined in Touch Creator multiple times in as many Touch Players as you like. And again, the content assigned to a particular display will be used independently by each individual Touch Player.

Assigning Content to Displays

Assigning content to particular displays is done via the configuration of the Touch Players in use. Within Touch Creator, you define multiple displays that constitute the stage your project is presented on. Each display has an individual name that is used in Touch Player to determine the content to be played.

In Touch Player you can configure the displays attached to the corresponding Mac. To have specific content shown on a particular display, the display must be assigned the same name in Touch Player as the display that shows the content in the Touch Creator stage. The image below shows the Display section in the Touch Player tab of the Touch Player Preferences window.

Also, in Touch Player you determine which attached display will act as the multi-touch interface. In the Touch Tracker tab you can both select the tracker driver used and the name of the corresponding multi-touch display.

Working With Multiple Displays

When deciding which particular hardware configuration to provide, you have to assess exactly what task each individual Mac has to cope with. This concerns all possible setups.

A basic setup with one display can be realized with a Mac Mini or with a Mac Pro. A Mac Mini will suffice if you want to provide basic touch interaction and trigger the playback of a video with reasonable resolution or a nice slideshow of images on a single multi-touch display. More complex projects are quite likely to require a Mac Pro.

The image below shows one Mac Pro and six displays, but you can use any number of displays between one and six. User interaction is possible on one display only, but all objects displayed on this Mac can be manipulated by the user if the project is designed this way. For instance, the touch display may show a button that starts media playback on another display attached to the same Mac.

With touch overlays, you can increase the multi-touch area of a setup. These devices are hardware frames that are mounted on top of displays to detect touches even on displays that aren't touch-capable. The image below shows how a touch overlay works.

You can use the above configurations in any combination in your projects. It must be reiterated that any Mac running a Touch Player must provide sufficient performance to cope with its particular task.

We hope this section could help you understand how to work with multiple displays in ~sedna touch. Good luck and have fun!

© ~sedna gmbh 2016