Growing the Grass

The grass was created using Maya’s Paint Effects. This created really good results from relatively little work and had the enormous advantage of built-in, optimized dynamics. We didn't have access to a fur plugin and it would have been impossible for us to create a similar “waving in the wind” effect using traditional dynamics, so Paint Effects was a real saviour

We love paint effects!

Lauren took Maya’s ready-made grass brushes and altered them to our liking, working mainly on the colour and texture aspects. We then used the “paint grid” option layer a few different types of grass on top of one another in varying densities to create a convincing look.

The riverbank reeds were also created using Paint Effects, but they presented a new set of problems. Paint Effects strokes do not show up in reflections, but since the reeds bordered on the river, they needed to. One option was to convert the strokes to polygons, but this resulted in a massive increase in the polygon count of the scene. Moreover, the polygons didn’t behave dynamically. Our solution was to approach the problem on a shot-by-shot basis. In some scenes we converted the visible reeds to polygons, turned off the polygon’s primary visibility and turned on its “visibility in reflections”. By doing this, the original Paint Effects strokes were rendered on the riverbank, while the reflections of the polygons were rendered in the water. Since the water is rippling, the reflected reeds appear to be moving, even though they are not.

The paint effects reeds don't cast reflections, but are visible in the reflections of the water.
An identical, hidden group of polygonal reeds cast the reflections.

Another solution was to render out tiles of reeds separately and then map these onto cards that lined the edges of the riverbank. This was a much lighter than the polygon conversion method, but the results were less effective.