Node Panels and Parameters

Chalice node panels provide access to all of the parameters and other controls available for each node type. The node panel is the main work area for adjusting the default parameter values. This chapter introduces the types of controls common to most nodes and explains how to use the various controls to set node parameters.

Overview of the Node Panel
Parameter Tabs
Info Tab
Setting Node Parameters
Using Tuners
Using Data Entry Fields
Animating Parameter Data
Creating Key Frames
Using Preset Parameter Values
Setting Global Variables

Overview of the Node Panel

The area on the left side of the Chalice interface, just below the menu bars, displays the panel associated with the currently selected node. The top portion of the node parameter panel usually includes the same information, icons, and menus, regardless of the node type. These include:

Type of Node

The node type (Disk Input, Blur, etc.) is always labeled in the upper-left corner of the panel.

Node Name

Chalice assigns each new node a unique name by default (e.g., "blur1"). However, you can rename the node at any time. Each node in the current workspace level must have a unique name. (Workspace levels become relevant when you group nodes, as described in chapter 7, "Managing Large Networks .")

Node names must conform to standard UNIX nomenclature (this holds for both IRIX and NT users). Do not use spaces or special characters such as the semicolon (;), backslash (\), ampersand (&), exclamation point (!), asterisk (*), or pipe (|).

To rename a node, key the new name for the node into the "Name:" field on the node parameter tab and press the Enter key. It is best to keep node names short but descriptive.

Tip:
Use the Comment field in the Info Tab to document any pertinent information about the node for subsequent reference. (You can read the comment at any time by clicking and holding the Info button on the node.)

Help Button

The question mark icon in the upper-right corner of the node parameter panel is a context-sensitive Help button. Click on this button to access the section of Chalice Help that describes that particular node type. (For more information about the Chalice online help system, refer to the Help Menu section of chapter 10, "Main Menu Bar .")

Expressions Checkbox

Many nodes feature an Expressions checkbox that enables you to key mathematical expressions (instead of a fixed numerical value) into certain parameters. Some expressions allow you to reference data from other nodes. This feature is described in "Setting Node Parameters ."

Key Framer

You use the Key Framer to mark specific frames in a sequence as key frames to animate node parameters. After you set the key frame values, the node will interpolate the "in-between" frames--the frames that fall between key frames--according to how you have set the parameters for the node. For specific instructions on using the Key Framer, see "Setting Node Parameters ."

Presets Menu

The Node Presets menu enables you to save specific parameter settings to a Presets file and reload the settings into other nodes of the same type in any grail file. This can save you from having to remember and reassign a complex set of parameter values that you want to reuse. For specific instructions on creating, deleting, and loading node presets, see "Using Preset Parameter Values ."

Undo button

Click the Undo button to undo the last change made to a node parameter setting.

Parameter Tabs

The lower section of the node parameter panel includes various parameter tabs that are specific to the node type. At minimum, all nodes include an Info Tab. Most nodes include more than one parameter tab, which you can select to display an additional set of parameters.

The following is an example of a typical parameter tab:

You activate a particular parameter tab in a node panel by clicking on the top of the tab. Then you set the parameters using popup menus, checkboxes, data entry fields, and tuners.

Popup Menus

Click and hold the left mouse button over a popup menu button to display the menu of available choices for that parameter. While still holding down the mouse button, move the cursor through the list of items in the menu and each item will highlight in turn. Lift up the mouse button while the cursor is over a highlighted menu item to select that option. The currently selected option is always displayed on the popup menu button.

Checkboxes

If a box is checked with a checkmark, it indicates that the labeled option is active, or "on." Checkboxes work like toggle switches: click a box that is checked to turn it off; click a box that is not checked to turn it on.

Data Entry Fields

Position the cursor over the field and click the mouse button to key in a specific numerical value for a parameter. Remember to press the Enter key when you are done typing to actuate the entry. See also "Using Data Entry Fields " later in this chapter.

These fields often come in pairs, with the left-hand field representing the X axis value and the right-hand field representing the Y axis value for the parameter. When appropriate, a data entry field for a parameter will be accompanied by a tuner and/or a STED button:

  • STED buttons are associated with any field and/or tuner that can be animated, as described in the section on "Animating Parameter Data ." The STED button has two icon states: gray indicates that the parameter is not animated, black, that animation has been activated.
  • A data entry field is often associated with a tuner dial that enables you to adjust the parameter value in the field by moving the dial rather than typing in numbers. For detailed information, refer to "Using Tuners ."

Info Tab

All nodes include an Info parameter tab. The Info tab displays basic information about the node image: frame range, resolution, bit depth, and number of channels. It also includes node caching parameters and a comment field, both of which may be modified by the user.

For nodes that accept multiple inputs such as composite nodes, the Info Tab will display information relevant to the first (top) input to the node.

Resolution

The Resolution parameter displays the X and Y dimensions of the imagery, expressed as a number of pixels. The left field contains the X (width) value; the right field contains the Y (height) value. If you wish to change the spatial resolution of an image, refer to the Scale or Crop node descriptions in chapter 17, "Movement Nodes ."

Bit Depth

The Bit Depth parameter displays the bit depth per channel, or pixel type, of the imagery contained in the node, such as 8- or 16-bits per channel, or floating point (32 bit) channels. If you wish to change the bit depth of an image, refer to chapter 14, "Conversion Nodes ."

Channels

The Channels parameter displays the number of channels used to compose the imagery in the node. If you wish to change the number of channels in an image, use the Channel Swap node, which is described in chapter 13, "Tool Nodes ."

Tip:
The information on the Info tab is also available in a handy popup display when you click and hold down the Info ("i") button on the node itself.

Cache Parameters

The Cache Size and Protect Cache parameters enable you change the default caching behavior for a specific node. Chalice always attempts to cache node calculations in case the data is requested again. When the RAM and disk caches assigned to Chalice get full, however, some data must be overwritten for new processes.

Chalice decides which node's cache is deleted first using an internal priority system based on how individual node data is accessed, such as the node last altered, a node frequently altered, a node with a monitor image in a buffer, or a node that branches (has outputs to more than one downstream node). You can, in a sense, re-weight this priority system by using the node caching parameters.

Note:
For more information, refer to "Memory Usage in Chalice " in chapter 4, and to the description of the Cache Settings panel in the Admin Menu section of chapter 10, "Main Menu Bar ."

Cache Size

The Cache Size parameter allows you to adjust the number of consecutive computations that Chalice will cache. The default setting is 1, which indicates that Chalice will cache the last computation only. A setting of 2 would mean that Chalice caches the last two computations, and so forth, up to 10, which is the maximum cache setting.

In most instances it is not necessary to change the default Cache Size setting. However, you may wish to increase the cache size for a particular node if you plan to frequently access node data out of the normal order--for example, when a downstream node uses data from more than one frame (Time Convolve, Time Stretch, or the video transfer nodes, e.g.), or when you are repeatedly accessing two or more different frames downstream, as when you need to compare the effect each parameter change has on the first and last frames in a shot.

Tip:
Be careful not to set the Cache Size any larger than necessary, because high memory consumption by the node cache can slow overall performance.

Protect Cache

This parameter, when checked, specifies that Chalice assign the highest priority to preserving the data cached for this node. It is best used for a node with multiple downstream branches, or for a node whose upstream connections are unlikely to change any further. This can improve performance while you make adjustments to downstream nodes.

Tip:
Do not turn on the Protect Cache parameter for more than a few nodes simultaneously, as this will consume substantial amounts of memory and negatively impact system performance.

Comment

The Comment parameter enables you to document pertinent information about the node by keying a comment into the text entry field.

Reading Comments

Comments are displayed by clicking and holding the Info (i) button on the node itself.

Creating and Editing Comments

To key in a comment, click the left mouse button in the Comment field and begin typing. If you wish to enter a carriage return, hold down the Alt key on the keyboard and press the Enter key. (Otherwise, the text will stream past the visible edge of the field to the left.) The Comment field scroll bars can be used to access portions of the text that extend beyond the field frame.

Alternatively, you can use a text editor to display and edit this text: with the cursor in the text field, press Alt-e to bring up the default text editor for your system (e.g., Jot or Notepad).

Note:
Chalice also includes a Comment node, which is described in chapter 13, "Tool Nodes ." Comment nodes may be used to create a conspicuous marker in the workspace to document any aspect of the shot you are creating.

Setting Node Parameters

This section outlines the procedures to follow to use several parameter controls that are common to most nodes:

  • Tuners
  • Data entry fields
  • STED buttons
  • Expressions checkbox
  • Key framer
  • Node presets menu

Data entry fields, and data entry fields with an associated tuner dial (which are called "tuners" for short), are used to adjust most parameter values. The descriptions that follow include tips and shortcuts for using these parameter controls, including how to enable animation of parameter values over time.

The expressions checkbox, node presets menu, and the Key Framer are all used to modify parameter data in a specific manner, as described later in this chapter.

Using Tuners

The Tuners available on many parameter tabs offer two ways to set parameter values: by adjusting the tuner dial or by keying a specific value into the tuner's data entry field. A data entry field is associated with every tuner. When you adjust the tuner, the corresponding numerical value in the data field to the left of the tuner will update accordingly.

The tuner dial has two controllers: a triangular pointer that slides back and forth across the top half of the tuner and a vernier dial on the bottom half. To adjust the tuner value with the greatest precision, click and drag the vernier dial back and forth.

The small triangular pointer indicates the current dial setting. The appearance of this pointer changes depending on the setting. To set a tuner to the default value, align the pointer with the pink vertical bar. If the current tuner setting is any other value, it is indicated by a blue vertical bar. (For some tuners, values can be set that exceed the intended range; in such cases, the pointer turns red.)

The tuner includes three small square buttons, arranged vertically, to the right of the tuner. These buttons enable you to adjust the sensitivity of the tuner.

  • Each click of the top button increases the sensitivity of the tuner (usually by a factor of 10).
  • Each click of the bottom button decreases the sensitivity of the tuner (usually by a factor of 10).
  • To determine (and adjust, if necessary) the sensitivity factor of the tuner, click the middle button to replace the dial with a text field containing the current sensitivity factor (e.g., "10"). You can then key a new value into this field, if you desire. (Click the button again to replace the text field with the dial.)

Tuners usually feature an associated STED button. This indicates that the parameter values can be animated over time, as explained in the section on "Animating Parameter Data ."

Using Data Entry Fields

Data Entry Fields are used throughout Chalice to enter numeric values and/or text, depending on the nature of the parameter. A field that is associated with a tuner dial will always take numerical values, while independent fields (without tuners) can be used for entering text or data.

Data entry fields often appear in pairs where the left field represents an X coordinate and the right field, a Y coordinate. Fields may also come in a row of three, where (moving from left to right) they control values for the Red, Green, and Blue channels respectively.

Shortcuts for Data Entry

Middle-click and hold the mouse button in a data entry field to display a "ladder bar" control--a vertical list of increment values you can use to select the magnitude of the changes to the value in the field. First, drag the mouse up or down to select the increment value you want for the adjustment, and then drag left or right on the same plane to decrease or increase the value in the field by the selected increment.

For example, a ladder bar might offer a vertical list of 100, 10, 1, .1, and .01. If the value in the field is 1 and you drag the mouse up to the "10" box in the ladder bar, when you drag left and right at that level the value in the field will increase or decrease by 10s: from 1 to 10 to 20, etc.; or from 1 to -10, to -20, etc.

For associated data entry fields (such as a row of three fields representing the Red, Green, and Blue channels respectively), there may be a gang control you can use to adjust all values equally. Middle-click and hold any gang control bar in the field row to use the ladder bar. Then as you drag horizontally to adjust the value, the values in all three fields will increase or decrease in equal amounts.

Animating Parameter Data

Animating a parameter refers to varying its value over time. In default mode, the value you enter for a parameter applies to every frame of the input sequence. If you change frames and reset the value, the new value replaces the old for every frame.

Using STED Buttons

Whenever a STED button is associated with a field or tuner, the values for that parameter can be animated. First, you enable animation by clicking the STED button:

Once you have changed the STED button from gray to black, Chalice will accept a different value at each frame for the associated parameter. To disable animation of a parameter, Alt-click the STED button to return it to its default (gray) state. When you double-click the STED button, the STED editor window opens to display the parameter value as a curve across a graph representing the input frames.

The most basic way to animate a parameter is to set a value for the first frame, and then go to the last frame and set a new value. Chalice will interpolate between these frames to create the intermediate values. For more control, however, the following methods are available, depending on the type and extent of control you need:

  • You can turn on Expressions to enter an expression into the parameter that controls the value at each frame.
  • You can use the Key Framer to tag specific frames as key frames.
  • You can open the STED editor window to adjust values with very fine control, including the ability to apply various function curves.

Use of the Key Framer and the Expressions checkbox are described below. To use the STED editor window, however, refer to chapter 9, "Space-Time Editor (STED) ," which explains the use of this powerful tool in detail.

Enabling Expressions

When you click the Expressions checkbox, any tuner dials on the parameter tab disappear and their associated data entry field lengthens to accommodate the entry of an appropriate mathematical expression into the field to control the processing performed by that particular node parameter.

Tip:
When an expression has been used to animate a parameter value, you can use the Expressions checkbox to toggle back and forth between a view of the expression itself and a view of the value produced by the expression at the current frame.

For more information on writing and using expressions, refer to Appendix B, "Chalice Expression Language ," or to the applicable node descriptions.

Creating Key Frames

A key frame in Chalice is a marker that delineates the start or end point of a segment that animates a specific parameter in an image sequence. In this sense, all image sequences have at least two key frames: the first frame and the last frame.

You can adjust the values of the first and last frame to control the start and end values of the interpolation for the parameter. And you can add key frames to a sequence to split the original waveform into a series of smaller segments, each of which can be adjusted individually for finer control of the animation.

You can control the animation of parameters using the Key Framer in conjunction with the Frame Controller and the available parameter controls. (This procedure is described below.) Alternatively, you can use the Chalice Space-Time Editor (STED), which offers more options, such as the application of various functions to segments. This method is described in chapter 9, "Space-Time Editor (STED) ."

Note:
To remove a segment, you must use the STED. New segments you create by adding key frames cannot be deleted using the Key Framer panel.

Key Framer Device

The Key Framer device in the top of the node panel displays a light that changes color to indicate current status: move the cursor over the button to display a Help Tag that explains the current state of the Key Framer. The "Key" button changes to its active state whenever a key frame can be set. Click the Key button to make the current frame a key frame.

Key Frame Navigation

Once you have created key frames, you can navigate directly from key frame to key frame at any time using the forward or back arrows in the Key Framer. This will update both the animated parameter values in the node panel and the monitor display, if a monitor for the node is open.

Using the Key Framer with the Frame Controller

For details on using the Frame Controller, see "Previewing Node Output " in chapter 5.

  1. To set a key frame, first you must click the STED button once to enable animation for the parameter (you do not need to open the STED window).

  2. The STED button will change from gray to black to indicate that parameter animation has been enabled.
  3. Then use the Frame Controller to go to the first frame that you want to specify as a key frame.
  4. Change the value of the parameter associated with the STED button you clicked.

  5. The "Key" button on the Key Framer will become active.
  6. Click on the Key button to make the current frame a key frame.
  7. Repeat this process until you have designated all the key frames you want.
  8. Use the Previous and Next arrows on the Key Framer to review and adjust the key frame parameter settings, if desired.

Using Preset Parameter Values

The Node Presets menu allows you to save and load parameter settings for a node. Once you are satisfied with the parameter values you have assigned to a particular node, you can save the parameters and then load these preset values into any node of the same type.

For example, if you have several image sequences that require the same color correction, once you are satisfied with the parameter settings for the Color Correct node you can save the settings and load them into other Color Correct nodes as you correct subsequent sequences.

Node Presets Menu

To save or load a preset, click and hold the Presets menu button on the node parameter panel to access the Presets popup menu.

Chalice will display a list including the following four options:

  • User Defaults
  • Factory Defaults
  • Save As User Default
  • Save As...

Saving Node Presets

The Presets menu provides two ways to save the current node parameter settings as defaults:

  • Save As : This option enables you to save the current parameter settings as a "custom preset," using a unique preset name. The Save As option will not overwrite the User or Factory Default settings. When you select Save As, Chalice will display the "Enter Preset Name" dialog box. Choose an appropriate name for your current parameters and press "Accept." This new preset will appear the next time you pull down the Presets menu for any node of the same type.
  • Save As User Default : This option saves the current parameter settings as the new User Default for the current node type. Each time you select this option, the current settings overwrite any previous User Default settings.

Restoring Factory Defaults

Once a User Default has been created for a node type, it becomes the permanent default, replacing the Chalice Factory Defaults, until the User Default setting is deleted or redefined. To delete a User Default and thus restore the Factory Defaults, hold down the Alt key while selecting User Defaults from the menu.

Loading Node Presets

The Presets menu provides three options to load preset parameter values into a node:

  • Select the unique name of a Custom Preset (created using Save As).
  • Select the current User Defaults settings (created using Save As User Default).
  • Select Factory Defaults to see the Chalice default settings.

Deleting Node Presets

To delete a node preset, hold down the Alt key while selecting the preset. A dialog will ask you to confirm that you want to delete the preset.

Setting Global Variables

A global variable is a name that is associated with a value, where the value can be changed at any time. A global name, preceded by the "$" to identify it as a global, can be keyed into any appropriate data entry field and Chalice will use the current value defined for the global.

Using a global in a data entry field, rather than a specific value, has several advantages. A global name can be an effective shortcut (typing "$PI," for example, instead of "3.141592..."). And when a global represents a value that must be changed at some point, only the definition of the global value need be changed, not all the specific instances of it in numerous nodes.

Editing Globals

Chalice provides a Globals window which lists each global variable and its current definition. You can use the Globals window to add, delete, and change the definition of globals. There are three default global variables which cannot be deleted: JOB, which can be redefined, and the constants PI and E, which cannot.

To open the Globals window, select "Edit Global Variables..." from the Chalice Edit menu. This will allow you to

  • determine the current values of global variables in the list.
  • redefine the values of global variables in the list.
  • add your own global variables to the list.
  • delete any user-created global variables.

Redefining Globals

With the exception of PI and E, all global values may be changed. To change a global, simply key a new value into the "Value" entry field.

Global variable settings are grail-file-specific. That is, any changes you make to global values will not affect the global values in other existing grail files.

Note:
A global variable can be redefined temporarily when batch rendering with chal by using the -D [name definition] option (see appendix A, "Chal ," for more information on rendering options).

$JOB

The default location of the Job variable is the directory from which you started Chalice. You can redefine Job to fit your current project.

Adding Globals

To create a new global, click the Add Global button in the Globals window. Chalice will add a new blank entry to the list. Then you can type a name for the new global into the "Name" field, and a definition into the "Value" field. Be sure that the name for the new global follows standard UNIX naming conventions and that all letters are uppercase.

Click the Accept button to actuate the new global and close the Globals window.

Deleting Globals

All user-created globals can be deleted. Simply click the red "X" next to the global you wish to delete to remove it from the list.

Using Globals in Data Entry Fields

To use a global variable, type the name of the global into any appropriate data entry field, preceded by "$." For example, you could type "$JOB" into the path field of a Disk Output node to represent the directory path defined in the "Value" field of the Job global.

If you later want to change the location to which image files are written by the Disk Output node, you simply redefine the Job variable by keying a new directory path into the "Value" field of the Job global in the Globals window list.

Note:
Redefining $JOB automatically triggers a rescan of all Disk Input nodes. For more information, refer to the node description in chapter 12, "I/O Nodes ."



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