ActiveShade Initialize and Update

Scanline ActiveShade rendering is a two-step process: First there is an Initialize pass, and then an Update Shading pass.

The Initialize Pass

Rendering can be slow. The initialize pass is meant to take care of the most time-consuming portions of rendering, to allow the update shading pass to take place as quickly as possible. Initialization includes the following steps:

• Evaluate the scene geometry into meshes.
• Apply space warps.
• Do transformations and clipping.
• Evaluate textures and shade materials.
• Perform optimizations to speed later processing, such as merging fragments from the same surface that are in the same pixel.

The result of initialization is a buffer. This is a compressed rendering that, like a G-Buffer, contains the rendering plus additional information used by the second step, update shading.

During the initialize pass, progress is indicated by a row of pixels (white by default) that traverses the top edge of the ActiveShade window.

The Update Shading Pass

Updating shading takes the buffer created by the first pass, initialization, and uses information in that buffer to change the color of pixels when you make changes to lights and materials in the scene.

During the update pass, progress is indicated by a row of pixels (white by default) that descends the right edge of the ActiveShade window.