Lyric Polygon Matte
The Lyric Polygon Matte lets you draw several diffent kinds of regular polygon-shaped mattes. The vertices can be rounded with a variable radius and the shape fill and outline can be separately controlled, allowing both filled and variable-width outline mattes to be constructed. A separate matte image or clip can be placed within the shape bounds.
This mask is often used as a garbage matte in conjunction with another matte to limit the areas selected by the second matte. This latter is achieved by using the Alpha Channel Intersection capabilities of all the Lyric Mattes. It is also sometimes used to produce polygonally-shaped vignette overlays.
The Lyric Polygon Matte filter includes a set of matte and output controls that are common across all Lyric matte filters. For a detailed description of these controls, please see the Matte Common Controls documentation.
For background information on mattes and their uses in Final Cut, please refer to the Lyric Matte Primer.
The Geometry section contains controls that govern the shape & placements of the matte.
The Shape dropdown menu lets you select the polygon shape.
The Origin point control can be used to position the center of the polygon. The best way to set up interactive shape create is to apply the matte to a clip already in the timeline, double-click the clip to bring it into the Viewer window and select the Filter tab. Place the timeline playhead within the clip containing the filter, so that the clip is visible in the Canvas. Now you can select the point control (by clicking on the circular '+' button) and then click and drag it's position in the Canvas. It may be useful to enable the Show Matte checkbox in the Output section in order to see both the image and the matte together while it is being constructed.
The Height and Width controls adjust the shape of the matte; checking 1:1 Aspect Lock will cause the Height control alone to be specify to diameter of a evenly-sized matte. Scale and Rotation can be used to further control size and orientation.
The Fill section contains controls that determine how the shape is filled. If Enable Fill is off, the shape is not filled, if it is on the shape will be filled with white (opaque) or the Fill Image/Clip if one has been dropped onto its clip well. Opacity controls the white-level in the fill, decreasing opacity reduces the fill color down to black through levels of gray, effectively reducing the opacity of the matte. Softness feathers the edges of the matte filling. If a fill clip or image is supplied, it will either be clipped by the shape or scaled to fit the shape, depending on the state of the Fit Clip checkbox.
The Frame section contains controls that determine how the shape is outlined. A frame outline is enabled via Enable Frame. Thickness controls the width of the frame. Opacity and Softness operate as they do for the fills, but only on the frame.
Enabling Rounded Corners applies a rounding to each corner of the shape whose radius is controlled by the Radius slider. Note that since the radius is the same on all corners, the maximum radius that can be applied is determined effectively by the shortest side, as the arcs from each end of that side meet.
The Matte Control and Output sections are common controls that are documented on the Matte Common Controls page.
Remember, you can stack several Lyric Matte filters in a single clip to make a final composite matte by setting their Matte Mixing menu to appropriate values: Add to Existing Alpha will combine selections, Subtract from Existing Alpha will remove some unwanted part of the matte and Intersect with Existing Alpha will make the combining mattes act like garbage mattes for one-another. You can also use the Final Cut crop tool as a final garbage matte; it is applied after all other mattes are applied.