While sculpting polymeshes in 3D you can use 6 different types of strokes: Dots, DragRect, Freehand, Colorized Spray, Spray and DragDot. These can be used with the alpha sculpting feature. To experiment with these different strokes we’ll use the Cylinder3D primitive as a starting point. Follow these steps: A DragDot stroke allows you to drag your brush around, to place your sculpting or painting at a precise point. Only the area under the mouse when the drag ends is affected. That’s very useful for a case where you might want to have a company logo or some other bit of text stamped onto the model. For our example, though, we’re going to get a bit more creative so that your imagination might be sparked to try even more interesting things. As you can see, this stroke allows us to very easily create an intricate pattern with only a simple alpha. What’s especially nice about this stroke is how precise it is. You can place your alpha instance(s) in exactly the desired position. This stroke draws a great many instances of the alpha very close together so that they blend into a single line. The closeness of each alpha to its neighboring instances is determined by how quickly you move the mouse. A slow stroke will create a uniform line (especially when lazy mouse mode is active), while fast movement will create a blotchy effect that is useful for some organic work. For this example, we’re going to use the stroke to add some rings around the column, separating it into sections. Add a few more rings as shown in below. Don’t be afraid to keep going over the same area to build up additional width or depth. The Drag Rectangle stroke draws a single instance of the alpha, which may be rotated while dragging the stroke. The alpha is drawn with its center point being where the stroke begins. As you move the mouse away from the starting point, the alpha becomes larger. As you move the mouse around the starting point, the alpha is rotated. As you can see, the DragRect stroke type is perfect for stamping any sort of design onto the model. Another use would be with a speckled alpha to draw pores on a person’s skin. Because you control the size and orientation of the alpha with every stroke, you can keep the stamps from repeating, thus preserving a naturally organic appearance. The Freehand stroke type is very similar to Dots. Both can be used with the LazyStep modifier to repeat the alpha in a regular way. The LazyStep modifer is remarkably useful any time you want to draw lines of repeated detail. You could trace a line of rivets along the seams in an aircraft’s panels, create cute little swirls of dots, etc. The Roll modifier is similar but instead of the alpha being spaced out as with LazyStep, it is stretched depending on the Roll Dist setting. Roll is specifically designed for tileable alphas so that an unbroken design can be created. These two stroke types splatter the model with semi-random copies of the alpha. There are settings to determine how far apart the alpha instances can be, how much they fluctuate in scale, how densely the instances are drawn (just a few scattered, or a lot), and how color is affected. The difference between the two stroke types is specifically in how each deals with color. Spray will cause the value of the currently selected color to fluctuate. Colorized Spray will affect its hue. Since we’re strictly sculpting in this tutorial, the color modifications don’t play a role and so we could use either stroke with exactly the same results. We’ll just use Spray. The Spray strokes are a very powerful way to quickly create randomized organic detail. Don’t forget that while we’ve used them strictly in a modeling capacity in this tutorial, they also work quite well with polypainting. That’s where you’ll really put the color features of these stroke types to good use. When you have finished experimenting you may want to reset the Standard brush to its original settings. The simplest way to do this is to press the Reset All Brushes button at the bottom of the Brush palette. Source.