Demorize Digital Signage Software

17.6. Filters

Rendering filters are used for applying visual effects to graphical objects. Some of the rendering filter effects have dynamic parameters that control their visual appearance. These parameters can be animated over time by adding a controller for the parameter on the timeline. This can for example be used to create transition effects that make objects appear or disappear in different ways. Other rendering filters are not of transition type but are rather static effects that apply some visual post-rendering effect to the object. This includes effects such as applying a gradient color overlay or drop shadow on for example a text object. Rendering filters can be applied to all types of graphical objects.

Rendering filters are added to an object in the properties view of the object. Right-click on an object to open its context menu and select Properties to open this view. In the properties view, select the Filters property and click on the button next to the text "(Collection)" to open up the filter editor. In this editor you can add and edit an object's effects and change the parameters of the effect. After you have added an effect that has dynamic properties, you can go to the timeline and add a controller for the effect parameter if you want to animate the parameter over time. Filters that have dynamic parameters automatically shows its parameters in the object's timeline context menu.

Adding rendering filters to an object may cause slow-downs of the presentation quality if the object is very large on the screen and your computer that is running the presentation is not powerful enough. These effects are accelerated by the graphics card hardware, but on low-end computers they may consume a fair bit of processing power if they are very large.

Rendering filters are limited to drawing within the defined rectangle of an object. This means that you need to make sure that the object that you want to apply a filter to is not transformed so that it extends outside its rectangle. In such a case, the filter will clip the contents of the object to its rectangle area. This is also important when you work with for example the drop shadow filter on an image object. Since the image object by default covers its entire rectangle, the drop shadow effect will not be visible since it does not fit within the image rectangle. In this case you have to scale the image down a little bit, by using the Scale property of the image, before you apply the drop shadow effect.