Ishida Tech Solutions, Ltd.
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When I create cross-platform children’s educational games on CD-ROM, it’s important to be able to fit a Mac version and a PC version of the game on 1 CD-ROM. The best way to do this is to create a hybrid CD-ROM that will work on either Mac or PC. If you can keep much of the “bulk” of the game in external folders (such as folders of audio files), then these folders only need to exist once on the CD-ROM and both sides can access them–saving lots of CD-ROM space in the process.

To create a cross-platform CD-ROM, you will need a Mac and some CD burning software that supports the hybrid format. Roxio’s Toast is your best bet. Toast has supported this feature for many versions. This example will use Toast Titanium 8 on Mac OS 10.5.3.

Step 1

Create a new Mac disk partition. Use the disk utility found in Applications->Utilities. You will put all the Mac files on this partition including any of the folders you intend to share with the PC side (like the “sound files” folder). When you choose a size for this partition, you need to stay under the physical limit of your CD-ROM, but since the Mac side will house the shared data, it can take the lion’s share of the space.

Step 2

Create a folder to store the PC files you plan on burning to CD-ROM. Determine what you want the PC side to be able to share on the Mac side and then create an alias (Command+L) on the Mac side of each file/folder you want to share. Copy the alias to the PC folder. Make sure the alias has the exact same name as the real file/folder–to do this, you may need to remove the word “alias” from it since Mac OS automatically inserts that on a new alias. Delete the aliases on the Mac side.

Step 3

Open Toast and click on the “Custom Hybrid” format on the left side. If you do not see this as an option, go to your Toast preferences and “enable legacy formats”. You will see 2 buttons–1 to select Mac files and 1 to select ISO 9660 files. Click the “Select Mac” button and then drag-and-drop the mounted disk image you created in step 1. Click the “Select ISO” button and then drag-and-drop the contents of the folder that contains your prepared PC files and the aliases to the files/folders on the Mac side. On the PC side, make sure the “Resolve Aliases” box is checked on. On the Settings tab, you will probably need to specify “Allow Macintosh Names” unless all of your PC files and the shared files/folders are 8 characters or fewer. This setting is basically just letting you use long file names that are supported by modern versions of Windows anyway.

Step 4

Burn your CD-ROM and then insert it in a Mac and insert it in a PC and make sure you only see what you would expect. The significant part is that the PC side that has the shared files/folders–the aliases look like real files and folders and the sharing of that data is completely seamless.