The final stage of creating the visuals is compositing. That involves combining the backgrounds and foreground animation together, and adding any special effects and color correction. This is easier with 3D animation than live action because animated elements can be rendered separate from a background, and combined according to depth. This is helpful because atmospheric effects are important.
In addition to backgrounds and character animation, I created some moving mist to make up the smoke of battle, some smoky wisps for closer shots, and the smoke from the cannons. We also need several shots of debris, for when the cannonfire hits the sides of the ships, and several different splashes for cannonballs that miss and men overboard. To add life to the island, we also needed seagulls.
Above is Shot 32. You can look at the rendered image, which is what Lightwave exports. It also exports a depth map, what Lightwave calls the z-buffer. The z-buffer displays how far away objects are from the camera. You can see that the captain, the object closest to the camera, is black, the pirate ship is grey, and the sky is white. Then we render out the background image, which fits together with the foreground.
Using the depth map, I can add my mist layer in so that it goes behind the captain and gets thicker as it gets further away. The depth map also lets me add a blur that simulates depth of field. The further a pixel is from the camera, the more blur is applied to it. Then I add my detail smoke over the top to tie everything together, and it’s time for the final color correction pass. Here’s one more shot:
Shot 28 makes a lot use of the z-buffer since it needs to simulate an enclosed space full of smoke. I could have rendered it with actual 3D volumetric smoke, but that would have taken too long. Simple 2D smoke applied in Adobe After Effects works almost as well. Where the z-buffer is black, the smoke is transparent, and where it is white, it is more opaque. That gives us our first smoke pass. I can also use the z-buffer to place an animated element, in this case cannon smoke, behind a specific object in the frame.
I then changed the color of the smoke to better simulate the light shining in through to gun ports, and added a red glow around to torches to look like they were illuminating the smoke layer. All this shot needs after that is the depth of field blur and some color correction, and it is finished. With only fifty shots, it didn’t take long to finish compositing the entire film, and all the image work was done. Of course, while I was working on that, my siblings were hard at work on the sound effects and music, which I’ll talk about next.