Brush Workshop 1: Random squares
Here is easy brush to build for quick abstract drawings. This will be a great occasion to try various parameters and get in touch with the controllers.
Select the felt brush preset in the default favorite brushes. Felt pen is a simple brush with standard parameters and few controllers, which make it an easy brush to modify and add behaviors to.
First, as the name says, let's select the square shape.
Then, instead of a traditional brush stroke, what we want here is a flow of separate shapes. This is done by going in the flow tab and modifying the shape interval parameter. At first the parameter doesn't go as high as we need to really separate the shapes but we can override the maximum value by dragging over the number on the right with our mouse or typing the number:
Looking at the brush preview, 125% seems good.
Note : the preview stroke is not the default one you see right now in your Black Ink. That's because I drew a new stroke myself in the preview area to have a better view of a simple pressure and speed increase. Try to make one yourself. If you like the default preview better, there is a button just below the preview area to get back to it.
Now back to the shape section, We're going to reduce the range of the size so we still have a change, but not that wide. Let's deploy the extended slider and set the minimum to 10 and the maximum to 20.
So we have some big squares, good.
Now let's drop in some controllers into our brush !
At the end of the shape controls, click on the small arrow to show two more parameters, Scale X and Scale Y. Let's deploy the slider to check their values.
They're set from 0 to 100%, which is perfect. So our scales can vary from 0 to 100 but don't have any controller to make the change happen. Let's add one. Click on the controller icon above the max value or press the c key.
Make sure to have the Scale X output selected and open the "Signals" folder on the left side of the controller editor.
Now we're going to take a "Random" node and connect it to the output. You can see in the preview the squares being stretched horizontally.
And do the same with the Scale y..
Let's try to draw something with our brush !
Having tried my brush, I feel like I'd like my opacity to behave differently. That's because we still have the default felt pen opacity controllers. Let's move to the opacity parameter in the controller editor, delete everything and plug a simple pressure node from the "Stroke parameters" folder.
Now here is a tip: Sometimes I feel like I don't have a very good control over low pressures and if I press just a little, the opacity goes up too fast.That's perfectly normal, this is the actual pressure applied on the tablet's pen and it's very difficult to control the pressure on your hand when it is moving.
But what we can do is modifying the signal from the tablet so the highest values of our opacity require more pressure.
Let's take an "Ease power" node from the "Math" folder and connect it between our pressure and the output arrow.
You can unplug the pressure node, put it on the side, plug the ease power in the output and plug the pressure back in the ease power's input.
Clicking on the button near the small curve on the ease power node, we can access its settings. Let's put 3 in the "power" field. We can see on the preview that the opacity is much more progressive.
Now for a quick math interlude: this node is a power function, it multiplies a value by itself a number of times. The effect of that is what the curve in the node's settings shows : lower values are even lower while higher values still go up to 1. This is why at a medium pressure we are calling a lower opacity but still get full opacity at full pressure.
Let's draw again !
It looks ok but we really need some colors into that. We can of course select any solid color we want but let's go for something a much more fun. Let's change the color mode to gradient:
and choose some nice colors:
Then open the controller editor to check how this gradient is applied:
Right now it is linked to pressure, which is a great idea but since we are already using the pressure for size and opacity, let's try something else. Replace everything by a speed node from the "Stroke parameters" folder.
In the brush preview the gradient doesn't seem to be entirely present and if we try out our brush, we may find that going up to the lighter blue requires a great and unpractical speed. The reason for that is that the speed value is actually very small. Unless you have a very fast hand in which case you may be ok
Once again, we can modify this value to make it more easy to use. This time we're going to simply make it higher. Let's take a "Mul" node from the "Operators" folder and insert it between the speed and the output:
Open up the Mul settings and set the B value to 5. Don't forget to plug the nodes together !
Note : A and B value can be set either in the node's settings for constant values or come from other nodes via the input arrow of the node. Here A comes from the speed node and B is constant.
And here we go, thanks to the inputs we've set for our brush, this picture was made in a few seconds without changing a single value.
Try other parameters and controllers and enjoy your unique brushes !