Working with Image Selections

After you make a selection, you can clear it, soften its edges, make it floating, move it, and change its opacity.

Clearing and Copying a Selection

You can replace the pixels in a selection with the current background color by pressing the Delete key, or by choosing Edit | Cut. (The Cut command also transfers the selection to the Clipboard.) Canvas X Draw replaces the selected pixels with the color currently displayed in the background color icon. Keep in mind that “deleting” a selection doesn’t leave a hole or transparent area in the paint object, unless the paint object has a visibility mask, as described later in this section.

If you want Canvas X Draw to recall a selection, be sure to save it before leaving Edit mode. See Saving and Loading Selections in Channels.

To place a copy of a selection on the Clipboard without clearing the area in the original image, choose Edit | Copy. When a selection has been placed on the Clipboard, you can paste it into another paint object in Edit mode, where it will become a floating selection, or paste it into the document to create a new paint object.

Feathering the Edges of a Selection

You can feather (soften) the edges of a selection so that it blends more naturally into the original image. Use the Feather command to soften the hard edge of a selection and spread the selection over a larger area.

To Feather the Edges of a Selection:

1. With a paint object in Edit mode, make a selection and choose Image | Select | Feather.
2. In the Feather dialog box, enter the number of pixels to feather the selection in the Radius text box. The larger the Radius value, the more Canvas X Draw softens the selection edge.
3. Click OK to feather the selection.

Pasting into Selections

The Paste Into command pastes the Clipboard contents into a selection in an image. This includes a selection in an image channel or a channel mask attached to an object.

The Paste Into command pastes anything that you copy to the Clipboard, including a vector, text, or paint object, an image selection, or a segment of a vector object.

You can use Paste Into to composite images and create effects that would otherwise be difficult to produce. For example, to simulate a picture on a television screen in a photograph, you can select the screen area and paste an image into the selection. You can move the pasted image within the selection to adjust the area that you see.

You can paste transparent objects into opaque images, or opaque objects into transparent images. The background of the image determines the opacity of the pasted selection.

To Paste into a Selection:

1. Place an object or selection on the Clipboard by choosing Edit | Copy or Edit | Cut.
2. Make a selection in an image (or a channel mask), and choose Edit | Paste Into. The Clipboard contents appear in the selection.
3. You can drag the pasted item or press the arrow keys on the keyboard to move it, to display the areas you want to see. When you finish adjusting the selection, deselect it to merge it into the image.

Floating and Moving Selections

You can move and manipulate a selection without affecting the original image by making it a floating selection.

To float a selection and fill behind it with the background color, hold down Alt and choose Image | Select | Float.

When a selection is floating, it sits on an invisible plane above the original image. When you type text in an image, or paste an object from the Clipboard, Canvas X Draw makes the text or pasted item a floating selection.

Moving a selection that is part of the original image creates a floating selection, but also leaves behind an area filled with the background color.

To Float a Copy of a Selection:

Make a selection in an image and choose Image | Select | Float.

Deselecting and Defloating Selections

Deselecting a floating selection makes it part of the original image.

To Deselect a Floating Selection:

Press Esc twice or choose Image | Select | None.

To Make the Floating Selection Part of the Image While Retaining the Selection:

Press Esc or choose Image | Select | Defloat.

Moving Selections

To move a selection, you can press the keyboard arrow keys or drag the selection with the Marquee, Lasso, or Wand tools. If a selection is not floating, it becomes floating when you move it.

To keep the pointer from interfering with your view of a small selection, select the Remote Move tool in the Painting tool palette and drag it anywhere in the drawing area. Canvas X Draw moves the selection in the direction you move the pointer.

Changing the Opacity of Floating Selections

You can change the opacity of a floating selection and make the pixels behind it partially visible. You can also change the mode to produce different effects.

You cannot make selections partially transparent in Indexed or Black & White image modes.

To Change the Opacity of Floating Selections:

1. With a paint object in Edit mode, select part of the image.
2. Click on the Background color icon in the Toolbox.
3. Select a color to use behind the floating selection. This color will start to appear when you make the selection transparent.
   • To use the Floating Opacity slider in the Channels palette to lighten a floating selection: Fill behind the selection with white or a light color.
4. Hold down the Ctrl key and choose Image | Select | Float. Canvas X Draw floats the selection and fills behind it with the background color.
5. Choose Image | Show Channels to open the Channels palette. Set the Floating Opacity value to less than 100 percent to make the selection become transparent and reveal the background color behind the selection.
6. To change the mode, choose a new mode from the Mode menu.

Modifying Selections

You can use the Expand, Contract, Smooth, and Border commands to modify selections in images.

These commands make it easy to fine-tune a selection by expanding or contracting the selection border by a specified number of pixels, or by adding or subtracting pixels based on color.

Expanding a Selection

You can expand a selection by adding a specified number of pixels to the selection border.

To Modify an Active Selection:

Choose Image | Select | Modify | Expand. Type a value in the Radius text box and click OK. Canvas X Draw adds the specified area to the selection.

Contracting a Selection

You can shrink a selection by subtracting a specified number of pixels from the selection border.

To Modify an Active Selection:

Choose Image | Select | Modify | Contract. Type a value in the text box and then click OK. Canvas X Draw subtracts the specified area from the selection and the dashed border contracts.

Smoothing a Selection

The Smooth command is useful after you have made a color-based selection that has left stray pixels inside or outside of the selected area. The Smooth command includes or eliminates the stray pixels to even out the selection. The value you type in the text box determines which pixels will be included or excluded in the selection at the border.

To Modify an Active Selection:

Choose Image | Select | Modify | Smooth. Type a value in the text box and then click OK. Canvas X Draw adds or subtracts pixels to the perimeter of the selection based on the radius number of pixels you specified.

Bordering a Selection

After you define a selection, you can select the area at the border of the selection by specifying an offset in pixels from the selection edge.

To Modify an Active Selection:

Choose Image | Select | Modify | Border. Type a value in the text box and click OK. Two dashed borders indicate the selected border.

Once you make a selection, you can use the Grow command or the Similar command to expand the selection to include similar colors.

Creating Objects from Selections

You can make new paint objects from image selections with the New Image from Selection command. This command converts a selection in an image into a new paint object in the same position on the image you are editing. This can be useful for “layering” image compositions.

The result of New Image from Selection is similar to moving a selection to a transparent “layer,” a procedure used in some image editing programs. In Canvas X Draw you can use separate transparent paint objects to create “layered” image compositions.

This operation doesn’t affect the Clipboard contents.

To Create a Paint Object from a Selection:

With a selection in an image, choose New Image from Selection in the context menu. To display the context menu, right-click within the selection.

New Images from Selections and Floating Selections

When you choose New Image from Selection, Canvas X Draw removes the selection from the image or deselects the selection in the image. The selection appears as a new paint object in the same location.

Whether a selection is removed from an image depends on whether the selection is floating. The opacity of the resulting object also differs for floating and non-floating selections.

If a selection is not floating, Canvas X Draw deselects it but otherwise doesn’t change the original image when you create an object from the selection. The selected pixels keep their original opacity in the new object.

If a selection is floating, Canvas X Draw removes the selection. The effect is the same as deleting a selection: the background color replaces the selected pixels, or, if the object has a visibility mask, a clear background replaces the selected pixels. In the new object, the pixels are opaque, regardless of their original opacity.

Clear Backgrounds in New Paint Objects

A paint object created from a selection always has a clear, rather than opaque background, and a visibility mask.

Paint objects are rectangular. If a selection is not rectangular, Canvas X Draw places the selection on a clear background. This is why creating a paint object from a selection is like transferring the selection to a clear overlay on the original image.

If you select Preserve Visibility in the Channels palette, a visibility mask preserves the transparency of all pixels in the image. You can paint or use filters without affecting clear areas.

If Preserve Visibility is not selected, you can erase to a clear background and affect all pixels by painting and editing.

Converting Selections to Paths

Canvas X Draw can trace a selection in an image to create a path (vector object) from the selection border. The Selection to Path command traces the active image selection border using the settings you specify. This is useful if you want to convert a selection border to a vector object that can be used as a clipping path, for example.

The accuracy of a path made from a selection depends on the settings you specify and the complexity of the selection border. A very complex selection border can result in a path with hundreds of anchor points, which can cause problems in printing and other operations.

Paths created from selections have no fill ink, black pen ink, and the current stroke setting.

To Convert a Selection to a Path:

1. Make a selection in an image.
2. Choose Image | Selection to Path.
3. Choose the settings you want and click OK. The selection in the image is deselected and a new vector object (or group of vector objects) appears in front of the paint object.

Selection to Path Options

See also:

• Saving and Loading Selections in Channels