Tuesday, May 22, 2012

More radiosity shots

Here is the rest of the radiosity screenshots I took over the long weekend. Keep in mind this only shows ambient light, this is why they are darker than what they should. Still a long way to go!

Friday, May 18, 2012

Radiosity Screenshot

Here is a quick update on the radiosity. In this image there is only ambient light. Sunlight will make it more interesting for sure.

Wednesday, May 16, 2012

20 Light Bounces

I rewrote the radiosity solution over the weekend, this time for the Voxel Farm. Here you can see some results for the same forest scene of the earlier video:

It is a bit tricky to understand the light in these pictures. Primary light sources like the sun and the sky are not shown here. You can only see the light that has bounced off the surfaces or went through the tree crowns, which are translucent.

There are no materials or any texturing. The green hue comes from the crowns and parts of the ground that are covered by grass. But don't pay too much attention to the colors. This was to see if the algorithm was working properly. Also keep in mind the crown polygons are there only to collect, scatter and reflect illumination. They are replaced by the instanced leaves.

I found I needed to get up to 20 bounces to get enough illumination down to the forest ground. Otherwise it was too dark.

Saturday, May 5, 2012

Video of a forest

As promised, here is a video of a forest:

Some stats about this video:

  • It was captured in realtime on an ATI 4770 at HD720p
  • Framerate was capped at 30 fps
  • It shows an area of 1 km x 1 km
  • It has seven LOD
  • It took 12 hours to generate in three VoxelFarm nodes
  • The generated mesh dataset is 100 MB

Some good news:

  • This is streaming over HTTP. Peak bandwidth was below 300K/seg
  • Mesh resolution can be increased, streaming can cope
  • LOD transitions are hardly noticeable

What needs work:

  • More diversity: This has only one type of tree leaves and two types of grass.
  • Needs more plants in the floor, bushes and baby trees
  • Shadows and global illumination
  • Billboard placement needs improvement
  • Better textures

Tuesday, May 1, 2012

Under the trees

Here are more foliage screenshots from Sputnik. It is the rest of the series I did over the weekend. As you can see the blobs are entirely removed, but they are still used to create the leaves and collect illumination.