Making the host call a "Format plug-in module" back with 'formatSelectorReadLayerStart'

Question

Hi all,
I have some problems reading layers in the Photoshop SDK, and I would be glad if someone could give me hand with them. The thing is:
To date, I have managed to write a Photoshop "Format" module plug-in that is able to open files on my own graphic format. So far, so good. The problem is, this graphic format includes additional layers that I would like to open in Photoshop as well. The CS4 SDK documentation defines for this task:
- Three module selectors called 'formatSelectorReadLayerStart', 'formatSelectorReadLayerContinue' and 'formatSelectorReadLayerFinish'
- Since version 10.0, a member of the 'FormatRecord' struct called 'layerData' that reads: "Set by plugin in Start to tell host how many layers are in the document"
Well, I have set layerData to a value different than zero during the 'formatSelectorReadStart' but, still, Photoshop does not call my plugin with the selector 'formatSelectorReadLayerStart'. What can I be missing here? is there something else I have to set to force Photoshop to read the additional layers? maybe an undocumented PiPl property that tells PS that the plugin is able to read such layers?
Any help would be greatly appreciated!
Thanks in advance,
- Oscar

Answer 1

/*****************************************************************************/static  void DoReadFinish (void)
     /* Test the ability to create the file inside a smart object */
     /* This flag also tells you which menu item was selected */
     // if openAsSmartObject is already true then you cannot turn it off
     gFormatRecord->openAsSmartObject = gData->openAsSmartObject;
     // every other time we open as smart, that should be confusing enough for a user!
     gData->openAsSmartObject = !gData->openAsSmartObject;
     /* Dispose of the image resource data if it exists. */
     DisposeImageResources ();
     WriteScriptParamsOnRead (); // should be different for read/write
     AddComment (); // write a history comment
Found the problem: the routine DoReadFinish() in SimpleFormat.cpp  ( sample file format plug-in in SDK for CS4) has the routine DoReadFinish() as shown above. I just needed to delete the 2 lines related to smart object. Everything works fine after that. I had overlooked that routine a bit I suppose but those 2 lines do not add much to the undestanding othe plug-in mechanism and they should be deleted from the example IMHO.