The “Sketchy Renderer”
We've received a number of comments about the renderer used in Dreadline, so I thought it would be interesting to some people if I talked about it a little bit. When we first started working on the game, we knew we wanted monsters to visit calamities, but we didn't really have a visual style worked out. I originally wrote what is known as a “deferred renderer” that works a bit like the Unreal and Unity engine. Unfortunately, we weren't really feeling it. At one point Steve remarked that the Titanic looked a bit like an old school Metal Gear level.
I spent some time looking at Steve's concepts, which tend to be very loose and have an amazing childlike innocence to them. I thought it would be cool to be able to play as a group of rampaging monsters in a world that looked like Steve's cute but twisted fairy tale illustrations. Steve agreed, but I wasn't quite sure how to start.
I decided it would make sense to attempt to copy the way Steve drew his pictures. Basically, he would make a black and white sketch, and then hastily color it in, sometimes going outside the lines. So, I decided to make a renderer that would do the same thing. First, I render all the visible objects with black and white textures that look like the outlines. I also use a technique a bit like the game Okami to produce the silhouette of the object, but also mess with it to make it look like it was more crudely sketched. Here is an example of the Titanic level's black and white pass:
Next, I do another pass of the visible objects using colored textures. The objects in this pass are also “bent around” a bit in order to make it look like it's coloring outside the lines. This pass is blurred to make it appear even smudgier. This is the point where lighting and shadows are also added. Here is an example:
Finally, the two passes are combined so there are the outlines, but the objects also get colored in. The renderer also adds additional effects at this point like bloom. Here is the final look:
And here is a close up of our character Ghost:
We're pretty excited about the final look of the game. I think I came close to giving Steve the tech he needs to bring his concepts to life. It may not be Crytek, but it looks unlike any other game I have seen, and that was far more important for us with this project. Feel free to contact me if you have any questions or comments at firstname.lastname@example.org