In Metabrush it is possible to create all manner of unique effects, as you can see in my tutorial on Metabrush brushes. In order to create the effects you desire, it is important to understand how to use the brush settings. Here I show you how to set them. I use an example to explain why you would choose particular settings.
As an example, I will use this image that I made previously and used for my Cutaway tutorial.
I opened the image in Metabrush and selected Tools from the toolbar at the top left. This brings up a second toolbar. I selected Source from that second toolbar. Choosing Source means that Metabrush will use my input image as the source for the color that will be painted.
Here I show you how to choose the brush you will paint with. Ignore this particular image, and focus on the menus and choices.
I chose a brush from the Lswirl brush group, brush 2/16. This brush makes those swoopy shapes. To find this brush, touch the brush icon on the top right toolbar, then the brushes menu comes up. The brushes are organized into groups. The groups are in a vertical column on the left of the brush menu. Lswirl is one of the groups, about halfway down the list. When you click on a brush group, the brushes for that group are shown, and you can select one. Here I show how I selected the Lswirl group, and the Lswirl brushes that came up for me to choose from. Once you have selected a brush, click again on the brush icon at the top of the screen to make the brush menu disappear.
Now select the size and opacity of your brush using the vertical sliders on the left side of the screen. In my Cutaway example, I set the brush size to about 75% of maximum, because I wanted to paint large swoops. I set the brush opacity to its maximum, because I wanted the brush strokes to be opaque.
Now we need to set the brush settings. The brush settings can be found by touching the 3-slider icon on the toolbar at the top right of the screen, just to the right of the eraser icon. Here I show how to set the spacing. Click on the Basic button, and move the Spacing slider. In the Cutaway example, I used maximum spacing because I wanted to see individual swoops when I painted, as opposed to closely packed swoop shapes. As you move the slider, the brush stroke image above the sliders will change. This image show what a brush stroke will look like with these settings. As you can see, using a large spacing means you can separate the individual swoops.
To set the variances, click on the Variance button. Variance refers to how much randomness there is. For position variance, a high variance means that the brush shapes will be scattered a bit around your stroke, whereas a low position variance means that all the brush images will be centered along your stroke. You can see this as you try moving the sliders back and forth. Rotation variance is similar, except that the randomness is in how much the brush images are rotated as you make a stroke. In my Cutaway example, I set both variances to their maximum positions because I wanted maximum randomness in how the brush images were being set down.
To set the dynamics, click on the Dynamics button. Dynamics refers to how the stroke characteristics will vary with the speed of your stroke. For example, setting the size dynamics slider far to the right means that the size of your stroke will get bigger as you stroke. Moving the slider to the left side has the opposite effect. There is a similar effect for the other dynamics settings. Try moving the sliders, and the affect on your brush strokes will be shown in the image above the sliders. For my Cutaway example, I set all of the dynamics sliders to their middle positions, which means that the dynamics would not vary as I stroked.
To set structure and shadow (these are called "extras"), click on the Extras button. Structure refers to how defined each brush image is, that is, how much it stands out. Shadow refers to the shadow cast by the brush image. Use the sliders to try out different settings for the structure and the size of the shadow. For my Cutaway example, I set both Structure and Shadow to their maximum settings, because I wanted to have high definition and relief for the brush images.
Using these brush settings, I painted all over the beginning image to create this result. From my explanation of the settings, above, you should be able to see how they affected the result.