Sunday, January 13, 2013

Sunny Bunny

Below is a new bunny render, lit by a new sky render with a solar elevation angle of 45°. Apart from the sky map and the exposure, the setup is identical to the bunny images in the previous post.

Bunny lit by 45° sun.

Here's a low dynamic range version of the sky render that I used to light the image above:

45° solar elevation angle.

Here's another new sky with a lower sun, shown here with the same exposure as the image above:

30° solar elevation angle.

I rendered these sky renders directly to equirectangular format. I rendered them at high resolution to more accurately capture the shape of the sun. The sun isn't visible in the images above because the sky around the sun is blown out. The images above are both re-exposed so that you can see the blueness of the sky, but I originally rendered them 3 stops lower to ensure that the bright sun could not exceed the half-precision floating-point maximum value (because the renders are saved as 16-bit OpenEXR images).

Here are LDR versions of the images with unmodified exposure:

45° solar elevation angle.

30° solar elevation angle.

By the way, the ground color in the bunny render doesn't match that in the sky render—the bunny render ground is tan, and the sky render ground is gray.

I also rendered some images of a gold bunny lit by the same 45° sun and sky, featuring photon-mapped caustics: