The Graphics Muse Tools are a set of plugins, brushes, and patterns designed for use with the GIMP.

The GIMP is the GNU Image Manipulation Program, a Photoshop-like application that runs on Linux, Unix, Windows, and even Mac OS X systems.

GFXLayers provides a more interactive and extensive layer alignment tool than the one provided by the GIMP. With GFXLayers you can line layers end to end, top to bottom, aligned along edges or centers and vertically or horizontally. Layer links and visibility can also be set, even if you don't change any layer alignments.

Table of Contents

1. Overview of the layer alignment process
2. A tour of the GFXLayers dialog window
3. Step 1: Managing your Anchor Layer
4. Setting edge alignment
5. Setting layer alignment
6. Changing layer groupings
7. Changing layer visibility
8. Configurable Features
9. Tips
10. Known Bugs

Overview of the layer alignment process

Aligning layers is fast and easy with GFXLayers. The process is always the same, so learn these simple steps first. More detail on each step can be found in the rest of this document.

1. Select the layers you want to align from the layers list by clicking on each layer name.
2. Holding the CTRL key down, use the right mouse button to click on one of the layer previews. This will make that layer the anchor layer.
3. Select the position for the layer anchor using the Anchor Position options or by dragging the layer preview around.
4. Select the edge alignment for the selected layers.
5. Select the layer alignment for the selected layers.
6. Click on the Apply button to change the layer alignment in your image.

A tour of the GFXLayers dialog window

The top half of the GFXLayers window has a preview area on the left and a list of layers from the source image on the right. The preview area can show outlines of all layers, filled outlines for selected layers and previews of selected areas. Each of these can be enabled or disabled using the Features menu. Below the list of available layers is a field displaying the current Anchor layer. An anchor layer is the layer around which all other selected layers are aligned.

The bottom half of the window holds the alignment and layer options you can set with this plug-in. On the far right are columns labeled Grouping and Hide / Show. These options allow you to set corresponding options in the Layers and Channels dialog for all selected layers.

The other columns at the bottom of the window will not be active until you select an anchor layer. Once this is done the columns options will become selectable. The first column, Anchor Position, sets the position for the anchor within the preview. Once the anchor is positioned, choose an Edge Alignment for all selected layers. This determines how the edges of all the layers will be aligned against the position of the corresponding edge of the anchor layer. Next, select the layer alignment. This option determines the direction layers are laid out from the anchor layer.

Step 1: Managing your Anchor Layer

In order to align your layers you must start with an anchor layer. This is the layer around which all other layers will be aligned. To get an anchor layer you must first select at least one layer from the list of layer names in the upper right of the GFXLayers dialog. Each layer name you select will cause either a preview of that layer or a colored box for that layer to be displayed in the preview area. Once you have selected at least one layer name, click on either a preview or a colored box (black outlined boxes are unselected layers and cannot be made the anchor layer) while holding down the CTRL key. This will make the layer the anchor layer. The layer name will be displayed in the Anchor Layer box. If you wish to change the anchor layer you can do so at any time by using the CTRL-click method on another layer preview.

Once an anchor layer has been chosen, you can align that layer using either the Anchor Position options or by dragging the preview/colored box around manually. To drag, just click and hold the right mouse button over the layer anchor preview and drag the mouse around. The dragging will not allow you to move the anchor layer outside of the black outline of the page. In order to use the drag feature you must have the Free Form option set in the Anchor Position options box.

Setting edge alignment

The Edge Alignment options determine how the edges of the other selected layers will be aligned to the anchor layer. As soon as you select one of these options the selected layers will be updated in the preview area. Note that you will get better results if you determine ahead of time the edge you want to align and then the direction you want layers to be laid out (using the Layer alignment option).

Note that aligning the edges of your selected layers to All Centers effectively stacks your layers on atop another in the order they are listed in the Layers and Channels dialog (which is the same as what is displayed in the layer names list in the GFXLayers dialog).

Setting layer alignment

The Layer Alignment options are used to line layers up one after another in the preview, with the edge of one layer up against the edge of the next. If you don't want your layers lined up this way, just leave this option set to Don't Change.

The other options in this box will line the layers up, starting with the anchor layer and followed by the highest layer in the layer stack down to the lowest layer, in the direction specified by the option chosen.

Changing layer groupings

This simple option is used to link layers as if you were using the Link icon in the Layers and Channels dialog. The advantage to using it here is that you have a slightly more visual display of the layers you are linking, especially if you Disable Outlines in the Features menu. You can also unlink a group of layers at one time as well.

Changing layer visibility

Like linking, this option allows you to set the visibility of a set of layers all at one time. The advantage of having this option in GFXLayers over doing it manually in the Layers and Channels dialog is that you can set the visibility of a group of layers without having to wait for GIMP to try and update each layer in the Canvas window. This allows you to experiment a bit with which layers to show before requesting the change.

Configurable Features

• Enable / Disable Preview: These options will either make the previews of selected layers visible or show only the filled outline of the selected layers. The default is to show the layer preview.
• Enable / Disable Outlines: These options will either show or hide the black outline of all layers, even if they aren't currently selected. By default this option is enabled.
• Readjust Stacking Order: When you select a layer its preview is generated (if it hasn't been selected previously) and then displayed. If you select a layer higher up in the list of layer names first, followed by a layer lower down in the list, and the two layers overlap, the lower layer will be displayed over the higher one. To fix this visual problem, just select this option. This option can be selected repeatedly to force the proper display of layer previews. The option has no effect on the stacking of the filled outlines, however, if layer previews are disabled.

Tips

• Did you select an anchor layer? You have to do that first!
• You can select your anchor layer first, then go back and select other layers to align with it.
• Clicking on a layer name after its been selected will deselect it, but will save any changes you've made to it. In this way you can align one set of layers to one anchor, then switch anchors and align a different set of layers to it, all before applying any changes.
• You can experiment with layer alignment without modifying your actual layers. If you don't like the layout, just use the Reset button to go back to the original layout. This only works if you have not used the Apply button yet, however.
• Changes to the layers made after each time you hit Apply can be undone using CTRL-z once. You can then use Reset to return the GFXLayers dialog to its original setting.
• Since GFXLayers doesn't save any session data, its safe to use on two images, using two instances of GFXLayers, at the same time.

Bugs

• GIMP 1.2.x does not update the Layers and Channels dialog if a plug-in requests changes to the Link and Visibility icons. The changes actually occur - links are made and visibility of layers changes - but the corresponding icons in the Layers and Channels dialog don't change. To fix this, close and reopen the Layers and Channels dialog or, if you have more than one image window open, switch images using the Image menu in the Layers and Channels dialog and then switch back to your image. Either method will force the Layers and Channels dialog to be updated.
• You must Enable Previews in order to select your Anchor layer. After the anchor layer is set, you can disable previews to improve performance when working with large layers.