I want to make a filter plugin like the "Noise", "Add Noise" coming with Photoshop. The "Add Noise" plugin not only provide a proxy preview in the dialog, but also provides a "real" preview in image window when I change the filter parameter.
The main dialog of this plugin is a modeless dialog. How to control in this case? The specific difficulties I had are as following:
1. If I modefy the image content by AdvanceState(), the image in Photoshop doesn't change unless the dialog is closed and return to photoshop.
2. If the dialog is a modeless dialog, how can I start a new process of filter.

Thanks a lot.