VDMX Layers
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Using the Layer Manager
To get things started off, take a look at the Layer Manager palette's window. The Layer Manager is used to create and delete new layers, change their order and composition mode, and "group" layers.
This window is fairly straightforward; to create a new layer, click the "Create Layer" button- to delete a layer, select it in the list and either click the "Delete" button or press the delete key on your keyboard. To group layers, select them in the list and click the "Group Selected" button. The rendering order of layers may be changed simply by clicking and dragging them within the list; layers may also be renamed by double-clicking their names in the list and entering a new name. To the right of the layers' names are pop-up menus for choosing the composition modes of each layer.
Rendering Order and Composition Modes
Much like Photoshop and many other image-editing applications, layers are the basic building block of VDMX. Without layers, nothing would be visible; movies, pictures, and Quartz Composer documents are displayed on layers. Each layer has a source- the source is the basis of what the layer looks like. The image that comes from the source is then run through the layer's FX chain, which is comprised of a series of video effects that modify the source's image. The resultant image is then composited with other layers- the order of the layers determines the order in which they are composited; layers at the top of the stack are composited atop the layers below them.
While layers render top-down, they may also be grouped. Groups are clumps of layers that are rendered together to produce a single image- the group. The resulting composited image may then have fx applied to it, and is free to be rendered as normal with other layers or groups. In other words, groups let you treat a stack of layers as a single layer- the group may be positioned or affected as a single layer, impacting all of it's component layers. Groups are an important way to organize or split up rendering.
For users familiar with GridPro's processing chain (a basic AB style mixer), this can be recreated with two layers inside a single group. With this setup each layer can have it's own fx chain, and once the layers are composited together fx may be applied to the mixed video stream.
Layer Windows
Once you've created a layer or two, you'll notice that they appear in layer windows which are used to manage more specific controls for individual layers.
A single layer window can contain multiple tabs which represent different layers, making it easy to adjust the interface of VDMX to fit your screen size - for smaller screens, you may want to have a single tabbed layer window (you will have to switch tabs to access some controls, but you will have more room for plugins and other windows). Each tab across the top of the layer window represents a different layer that you can control.
The order of the tabs corresponds to the rendering order of the layers- top to bottom in the Layer Manager is analogous to left to right in the layer tabs. Clicking on a tab makes it's layer visible in the layer window, allowing you to edit it's various parameters. If you want to make a new window, just "tear off" the layer tab- click and drag on it, and release the mouse once it's outside the tabs; the layer whose tab you dragged out will appear in a new window. To get rid of a layer window, simply click and drag the layer tabs in it to the tabs in another window. Please keep in mind that this can potentially be misleading- while the Layer Manager displays all the layers all the time, the tabs in a Layer Window only display the layers contained in that window. For example, if I have three layers (creatively named 1, 2, and 3- in that order), i can "tear off" layer 2, and put it in it's own window. At this point, I would have two windows- one with layers 1 and 3, and the second with layer 2; even though the tabs for layers 1 and 3 would be adjacent to each other, the rendering order would still be 1-2-3.
Layer windows contain a large variety of controls for the layers they contain; their layer tabs indicate and allow you to adjust rendering order, the interface elements inside the "Source Type & Composition" box allow you to determine what kind of layer it is (movie, quartz composer, or tap- and if it's a tap, what it's source is), the layer's composition mode, and it's opacity. At the bottom of the layer window is another box, with controls for adjusting the layer's size and position. The middle area of the window is for the FX-chain and FX presets. Visual effects can be added to layers using the Video FX palette window.
Layer FX Chains
Immediately below the layer composition controls in a layer window is the layer's FX chain. Similar to the FX chains from GridPro, this is a series of video effects what are applied, one after the other, to the layer's source. The order the effects are placed in can have as much of an impact on the output as the choice of the effects themselves. Unlike GridPro, FX in VDMX have their own composition mode, meaning that the effect is applied to the incoming video stream, and the resultant modified image is then composited atop the incoming stream using the chosen composition mode. By default, an fx's composition mode is "source atop", which saves processing time and behaves similarly to the standard wet/dry controls found in GridPro.
Video effects are loaded from the Video FX Palette. This window is fairly straightforward- on the left side is a list of FX categories. Click on one of these categories, and the right-hand list will populate with a list of all the fx in that particular category. The fx in this may be created by dragging them into any fx chain, or by right-clicking on them (which opens a contextual menu for deciding the chain the effect will be created in), or by clicking on the triangle to the right of their names, which opens the aforementioned contextual menu.
Once you've added an effect in a layer's FX chain, you're free to change any of its parameters, move it to a different place in the FX chain and or remove it. FX may also be moved from one chain to another simply by clicking on any area of the effect not occupied by other interface elements and dragging it to the desired destination. FX may be collapsed by clicking the disclosure triangles in their upper-left corner, and may be toggled on or off by using the enable/disable immediately below the disclosure triangle. The wet/dry slider fades the effect in and out- if the effect is faded all the way out (or disabled), it's processing is bypassed entirely and your overall FPS out may get a shot in the arm. To delete an effect, click the "x" in it's upper right-hand corner.
At the top of the FX chain in layer windows, you'll notice a pop-up menu adjacent to the text "Load Preset:". The items in this menu correspond to layer-specific fx chain presets, which are available to every existing layer's fx chain. Choosing an item from this menu replaces the fx chain of the visible layer- and *only* the visible layer- with the selected preset. This is different from the "Layer FX" presets (to be discussed later along with the Preset Manager), which affect all fx chains for all existing layers. The button immediately to the right of the layer-specific fx chain pop-up menu labelled "Save/Delete Preset" allows you to, sensibly enough, save or delete layer-specific presets.
Layer Source Type & Composition
Immediately below the tabs running across the top of layer windows, you'll notice a collapsible box labelled "Source Type & Composition". This box, as you might expect, holds a number of interface items which allow you to adjust what kind of layer it is (movie, quartz composer patch, or tap), the layer's opacity, and rendering mode. The box is collapsible because many of the controls inside it are duplicated in other parts of the application- if you like having this particular set of controls visible, go for it. Otherwise, don't worry- you'll see these controls in other windows (such as preview windows and the layer manager). With the exception of the "Source Res?" toggle, the contents should be fairly straightforward. The two most commonly used controls are the layer's composition mode, which determines how it's blended with the layers below it, and it's opacity slider- which is coupled for convenience with a show/hide toggle. The "Use Source Res" toggle determines whether each layer or group is rendered at it's native resolution, or at the resolution of the main output window- this can potentially have a huge impact on performance. By default, layers and groups default to source-res processing- under most circumstances, this is typically more efficient; all this changes if the footage you're working with is larger than your output window (a situation which makes sense to avoid, as it wastes your computer's resources).
Layer Size & Position
Similar to the collapsible box containing the visible layer's source type and composition controls, there's another box at the bottom of the layer window labelled "Layer Size & Position". This box houses a set of controls used to adjust, not surprisingly, how big and where the layer is positioned. Please note that these controls are meant to be used during layer setup, and *only* during layer setup- they are heavily optimized to ensure that the layers are processed without losing any resolution, and as such there's a lot of buffer management associated with their use. These controls are intended to be used more for setting up projections in non-standard environments, as opposed to tweaking them live to zoom or pan; this box is collapsed for a reason (and may wind up getting moved somewhere slightly less obvious in future revisions). There are video effects which may be placed in any layer that reproduce the functionality here, and do so with a significantly more usable interface; just check out the "Geometry Adjustment" effect category in the FX palette, which is described in the next section. The "Auto-scale" toggle located in this box simply stretches the layer to fill the output window. If the layer's source footage doesn't match the aspect ratio of your output window, this will result in distortion, which is why it's off by default.
Layer Source (Movie, QTZ, Text) Controls
The Layer Controls plugin is used to access the controls for any media that is being played back on a layer, such as the transport (time, speed, volume, scratch) controls for a movie, or the inputs for a Quartz Composer document. The controls for a layer exist even when not being viewed by a plugin, making it possible to use a single Layer Controls to set up and manage multiple layers at a time.
All layers have sources- the source is the basic video source that every layer starts out with. Currently, there are five basic layer source types: Quicktime movies, Quartz Composer documents, text files, live inputs, and video taps. A layer's source type may be explicitly set in the "Source Type & Composition" box, or by triggering cells in a media bin.