Jay Ingle - lead developer, designer, and artist:
Let's look at how I animated some lava. Here is my first attempt. Not very smooth, but it does show basically what I am aiming for.
To make the animation appear more smooth, I decided to start with moving a ball up and down, and to the side, and then drawing the lava over those areas.
Which results in a smoother animation:
However, now it appears to me that the up and down motion is inconsistent. So to clean that up, I decided to use a guide line. This helps me to make sure that when the lava moves up, it also moves down with the same number of pixels, following the guide line.
However, I did make the top of the lava a bit unbalanced, because I want the slight impression that it is reaching up and trying to grab you. We are certainly improving in smoothness and consistency. I also created a lava spray particle effect, with randomized timing and amount of particles.
The final idea I had was to layer the effect. So I took the animation, switched up the frames so it appears to be moving in the opposite direction, darkened it, and moved it up a couple pixels. It took some work to offset the animation so that it looks nice next to the regular lava.
And there we have it. Here is a full scene so you can see how it will appear in the actual game. I hope you like it!
