Using Operators for Shapes

If there is an image or image sequence in the workspace that you want to use as a shape, you can use it (or a small portion of it) as the shape. You can crop the shape, resize it, and select the source channels and color depth.

An advantage of this method is that you can use images that are already processed (for example, keyed and color corrected).

Warning: Since multi-frame shapes use a lot of memory, do not use an entire clip unless you need to. Likewise, do not use a full-resolution source operator for a shape. The Particles operator always needs random access to all frames, so it stores the entire range of frames in memory at full resolution. This, in turn, can affect the performance of the Particles operator.

Often one or a few frames is enough for the effect. If you only want one frame and the operator has many frames, save (render) the image, and then import the shape instead.

It is easy to create shapes from scratch. For example, you can use the Paint operator. Choose File | New and create a Paint branch with the desired image size (such as 128 x 128 pixels) and length (one or a few frames). Draw the artwork and rename the Paint operator to make it easy to find when you select this operator for the shape.

Note: If you want to use a small portion of a large image, you may want to note its location while viewing the operator for the image so the crop position is easier to set in the Size fields. Or you can crop the footage using the Footage operator.

To use an operator as a shape:

1. Select the particle type in the Workspace panel.
2. Click Shape to show the Shape controls. See Shape Controls.
3. Click Operator.

The Operator Picker dialog appears.

4. Select the operator you want, and click OK.

The name appears on the Operator button, the image (or image sequence) appears in the shape viewer, and the shape automatically becomes the shape for the particle type.



5. To decrease the size of the image(s), you either crop or resize it. By default, the method is set to Resize. For the Resize method, you can set only the Size fields.

Use Lock to change the Size values proportionally. You cannot increase the size of the original shape.

6. If you set Method to Crop, you can also set the Offset fields.

The maximum X Offset is the width of the source image minus the Width setting. The maximum Y Offset is the height of the source image minus the Height setting.

7. From the left Channel list, select which channels to use as the source of the shape.

For example, use RGB or RGBA depending on whether you want the alpha channel to be used by the shape. (This still applies to Gray shapes since the alpha channel can be added to the red, green, and blue channels to create the grayscale image for the Gray shape.)

8. From the right Channel list, select the color depth (Color or Gray).

When a shape is set to Gray, the pixel value always represents the transparency (black is transparent, gray is semi-transparent, and white is opaque). For more information, see Choosing a Shape Type.