MSAA

Multi-Sampled Anti-Aliasing (MSAA)

The algorithm

• Each pixel is rendered once, but is saved multiple times in a bigger frame buffer.

• The frame buffer is then resolved to the standard resolution to create an anti-aliased image.

• The algorithm smooths only the edges of polygons.

• When there are no real polygons to render, such as on polygons with alpha textures, the edges remain aliased.

Advantages and disadvantages

The main advantage to MSAA is that the pixel is shaded only once.

The main disadvantages are:

• Bigger frame buffers (such as color or Z buffer) based on the requested number of samples.

• Only polygons are anti-aliased. Alpha textures and screen space effects, such as fluids or shadows remain aliased.

How to enable

MSAA is enabled from the configuration file: antialias à msaa à enable.

Requirements

MSAA can be used when one of the following render pipelines are enabled.

Default

• DOF HDR B

Parameters

You can set the parameters manually. You can also let the engine set the parameters through the parameter nvPreset.

Count

The number of multisamples per pixel.

• 4 means four times the render screen size.

Quality

The image quality level.

• The higher the quality is, the lower the performance.

• This number is interpreted by the graphics driver. For simplicity, set this number the same value as count.

nvPreset

• Set to None.

MSAA + DOF HDR B

Only the scene meshes are MSAA anti-aliased. Subsequent render passes are not anti-aliased.

Items such as HDR, refractions, fluids, shadows may still be aliased. In fact, some passes and effects use a custom form of anti-aliasing. Whether a pass is aliased depends on its implementation.

You can enable both MSAA and FXAA.