Creative Communities of the World Forums

The peer to peer support community for media production professionals.

Activity Forums Adobe After Effects HOW TO do brush strokes without trapcode…

  • HOW TO do brush strokes without trapcode…

    Posted by Eric Barker on August 28, 2007 at 9:53 pm

    I’ve been experimenting all day, and I’ve finally come up with a method of creating realistic looking brush strokes without Trapcode Particulate. And actually, this method has the potential of looking a little superior. I’ve decided to write up a tutorial on the subject, since it tends to come up quite often.

    1. Create a composition, the dimensions of your project, and title it “Tip”. Create a solid of the color you wish to paint. Drag the solid to your timeline.

    2. Now we’re going to create the paint brush tip. This is the equivalent of a Photoshop brush. The brush stroke will look more realistic if it’s constantly changing as it moves (as Photoshop brushes do). For that, we’ll use a partical generator, “CC Partical Systems II”, to generate the tip. Don’t worry that it doesn’t leave behind a streak, we only care about the momentary brush tip for now.

    Find the effect “CC Particle Systems II”, and add it to your solid layer. What we’re after is a particle generator that has no velocity, generates a fairly sparce particle field, with a relatively high birthrate (which means lowering the longevity). Set ALL of the physics perameters to “0” (gravity, velocity, etc). Set the particle type to “Lens Convex”, birth and death size to something small (I chose 0.08 and 0.04 respectively). Size Variation to 100%, Opacity Map to “Constant” and Max Opacity to “100%”. Now adjust your birth rate and longevity to something that looks like a spare ink splotch that changes fairly quickly.

    3. Now, create the path your brush stroke is going to take. Normally, we would define the path through the “center” parameter on the particle generator. But this time, we’re going to use the good old layer “position” parameter. Make the path very slow, much slower than you probably want the brush to actually move, so that it’s traveling no more than 2 or 3 pixels per frame. Adjust the in and out points of your stroke layer so that they’re no longer or shorter than your path time.

    4. Create a new composition with the same dimensions and call it “Paint Stroke (slow)”. Drag your “Tip” layer into it. Now for the magic ingredient. It’s a plugin called “CC Time Blend”. This will take every frame, and blend it with all the previous frames. It’s sort of like an echo, but much less processor intensive, and repeats EVERY frame, not just a certain number. The one thing be aware of with “CC Time Blend” is that it uses the software’s frame buffer to keep track of the older frames, not the timeline. So, you’ll continually want to choose “Edit > Purge > Image Cache”, after you make any changes. Set the “Accumulation” parameter to “100%”. Purge your image chache, and test it out. If everything went correctly, you should have a very nice looking paint stroke.

    5. Now, finally, you probably want to have the stroke move a little more quickly than it is. You’re going to have to render out the stroke you have now, and adjust it with the “Time Stretch” or “Time Remapping” (from the Layer > Time menu). You CAN NOT simply precomp your brush stroke into another composition, in this case, due to the way “CC Time Blend” handles time changes (even from within another comp).

    However, in the end, after you speed up your stroke to get your desired effect, you should have a very nice brush stroke that looks like an animated Photoshop brush.

    Have fun!

    Perry-david Van dillen replied 15 years, 2 months ago 3 Members · 2 Replies
  • 2 Replies
  • Nick Allen

    January 21, 2011 at 12:12 am

    I seem to be having trouble once I apply the CC Time Blend onto the Tip layer in the new comp. I can see the stroke a little bit when the Accumulation is at 75% but when I change it to 100% it disappears. Even after i purge cache after I made the changes. Any ideas? Thanks

  • Perry-david Van dillen

    June 22, 2011 at 1:05 am

    In step four make sure you’re dragging your “Tip” composition into the “Brush Stroke (slow)” composition (not just copying the layer into the new composition). Also, set Transfer to “Color” under the CC Time Blend options. That was the only transfer mode that seemed to work for me.

We use anonymous cookies to give you the best experience we can.
Our Privacy policy | GDPR Policy