13.17. Gfig

13.17.1. Overview

图 16.322. The same image, before and after using Gfig

The same image, before and after using Gfig

Original image

The same image, before and after using Gfig

Filter Gfig applied


This filter is a tool: You can create geometrical figures to add them to the image. It is very complex. I hope this paper will help you.

When using this filter, elements inserted in the image will be placed in a new layer. So the image will not be modified, all modifications occurring in this layer.

13.17.2. Starting filter

You can find this filter through FiltersRenderGfig

13.17.3. Options

图 16.323. Gfig filter options

“Gfig” filter options

The tool bar

At the top of dialog, you can find a set of icons which represents the functions of this filter. Help pop-ups are explicit.

Functions for object drawing

On the left part of tool bar, you can find some functions for object drawing. You enable them by clicking on the corresponding icon. You can create the following objects (note that Control points are created at the same time as object):

  • Line: With this tool, you can draw lines. Click on Preview to mark start point, then drag mouse pointer to the end point.

  • Circle: With this tool, you can draw circles. Click on Preview to mark center, then drag mouse pointer to the wanted radius.

  • Ellipse: With this tool, you can draw ellipses. Click on Preview to mark center, then drag mouse pointer to get the wanted size and form.

  • Arc: With this tool, you can draw circle arcs. Click on Preview to set start point. Click again to set another arc point. Without releasing mouse button, drag pointer; when you release mouse button, the arc end point is placed and an arc encompassing these three points is drawn.

  • Regular polygon: With this tool, you can create a regular polygon. Start with setting side number in Tool Options at the right of Preview. Then click on Preview to place center and, without releasing mouse button, drag pointer to get the wanted size and orientation.

  • Star: With this tool, you can create a star. Start with setting side number (spikes) in Tool Options at the right of Preview. Then click on Preview to place center and, without releasing mouse button, drag pointer to get the wanted size and orientation.

  • Spiral: With this tool, you can create a spiral. Start with setting spire number (sides) and spire orientation in Tool Options at the right of Preview. Then click on Preview to place center and, without releasing mouse button, drag pointer to get the wanted size.

  • Bezier's Curve: With this tool, you can create Bezier's curves. Click on Preview to set start point and the other points: the curve will be created between these points. To end point creation press Shift key when creating last point.

Functions for object management

In the middle of tool bar, you can find tools to manage objects:

  • Move (Object): With this tool, you can move the active object. To enable an object, click on a control point created at the same time as the object.

  • Move (Point): With this tool, you can click-and-drag one of the control points created at the same time as object. Each of these points moves the object in a different way.

  • Copy: With this tool, you can duplicate an object. Click on an object control point and drag it to the wanted place.

  • Delete: Click on an object control point to delete it.

  • Select: With this tool, you can select an object to active it. Simply click on one of its control points.

Functions for object organisation

At the right of tool bar, you can find tools for object superimposing (you can also get them by clicking on the drop-down list button if they are not visible). You have:

  • Raise/Lower Selected Object: With this tool, you can push the selected object one level up or down.

  • Raise/Lower selected object to top/bottom: self explanatory.

Functions for object display

The drop-down list in tool bar offers you some more functions:

  • Back/Forward: These functions allow you to jump from one object to another. Only this object is displayed.

  • Show all objects: This function shows all objects again, after using both previous functions.

Preview field

Preview comes with several options:

Settings

In this area, you have several options to work with this filter.

Tool Options

This area shows tool options.

Stroke

If this option is checked, the object will be drawn. Two buttons are available, to select color and brush type.

Filling

With help of this drop-down list, you can decide whether and how the object will be filled, with a color, a pattern or a gradient.

Show grid

If this option is checked, a grid is applied on Preview to make object positioning easier.

Snap to Grid

If this option is checked, objects will align to the grid.

Show image

When this option is checked, the current image is displayed in Preview. If not checked, a white surface is shown and neither stroke color nor brush type are shown.