J6/OpenGL/Antialias

Full screen antialiasing (FSAA) is a feature of the graphics card, which reduces jagged oblique edges of geometry in 3D graphics such as OpenGL. This is typically achieved by applying a blurring raster filter on the rendring buffer using a vicinity of 2 or 4 etc. adjacent pixels.

Examples

Straight oblique lines
Wireframe with light
Geometry based on curved font lines

Enabling

OpenGL extesions with support from platform-specific API (AGL, WGL, XGL) allow to discover and enable FSAA from the application, though it requires complex and non-portable coding.

It is possible to control FSAA on a specific platform with a particular graphics card from the display control panel. For example on Windows, from Control Panel (or desktop context menu) select Display Properties | Settings | Advanced. Select your graphics card. Select 3D OpenGL settings. Locate Antialiasing.

There may be performance penalty proportional to enhanced quality.

Texture Antialias

The antialiasing settings may not affect textures. However, a specially prepared texture can reduce jagged lines. Typically, a smoothing filter, such as Gaussian 3x3 or 5x5 convolution can do the job.

When defining the texture with gsgentexture2D, it provides override possibility to parameters like GS_TEXWRAP and GS_TEXFILTER. To make smooth textures, use

GS_TEXFILTER=: GL_LINEAR

Issues

Java front end does not show geometry antialising, probably because it uses software OpenGL. However, Java Native OpenGL does show it, e.g.