Most of the brushes supplied with GIMP fall into this category. They are represented in the Brushes dialog by grayscale pixmaps. When you paint using them, the current foreground color (as shown in the Color Area of the Toolbox) is substituted for black, and the pixmap shown in the Brushes dialog represents the mark that the brush makes on the image.

To create such a brush: create a grayscale image in gray levels, where black is fully visible, white is transparent, with gray levels in between. Do not use transparency for these brushes. Save it with the .gbr extension. Click on the Refresh button in the Brushes Dialog to get it in preview without it being necessary to restart GIMP.

Brushes in this category are represented by colored images in the Brushes dialog. They can be pictures or text. When you paint with them, the colors are used as shown; the current foreground color does not come into play. Otherwise they work the same way as ordinary brushes.

För att skapa en sådan pensel, skapa en liten RGBA-bild:

Select File → New… from the main menu.

In the Advanced Options, set for example the Color space to RGB color and set Fill with to Transparency.

Draw your image. Contrary to grayscale brushes, transparent areas here will be drawn transparent.

Select File → Save… from the main menu to first save your image as an .xcf file to keep its properties.

Select File → Export As… from the main menu to export the image as a brush with the .gbr extension.

In the Brushes Dialog, click on the button Refresh brushes .

Your brush appears among the other brushes. You can use it immediately, without restarting GIMP.

	Tips
	When you do a Copy or a Cut on a selection, you see the contents of the clipboard (that is the selection) at the first position in the brushes dialog. And you can use it for painting.

Figur 7.16. Markering till pensel efter kopiering eller urklipp

Brushes in this category can make more than one kind of mark on an image. They are indicated by small red triangles at the lower right corner of the brush symbol in the Brushes dialog. They are sometimes called "animated brushes" because the marks change as you trace out a brushstroke. In principle, image hose brushes can be very sophisticated, especially if you use a tablet, changing shape as a function of pressure, angle, etc. These possibilities have never really been exploited, however; and the ones supplied with GIMP are relatively simple (but still quite useful).

Du kommer att få ett exempel på hur du skapar sådana penslar i Animerade penslar

These are brushes created using the Brush Editor, which allows you to generate a wide variety of brush shapes by using a simple graphical interface. A nice feature of parametric brushes is that they are resizable. It is possible, using the Preferences dialog, to make key presses or mouse wheel rotations cause the current brush to become larger or smaller, if it is a parametric brush.