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