Alpha masking: Difference between revisions

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[[Alpha masking]] refers to a special case of [[alpha blending]] where all pixels are rendered as either fully opaque (100% alpha) or fully transparent (0% alpha) with no partial transparency. This can be treated as a special case because it does not require alpha sorting in order to produce visually correct results. This provides a significant performance win over an equivalent alpha sorted material.  
[[Alpha masking]] refers to a special case of [[alpha blending]] where all pixels are rendered as either fully opaque (100% alpha) or fully transparent (0% alpha) with no partial transparency. This can be treated as a special case because it does not require alpha sorting in order to produce visually correct results. This provides a significant performance win over an equivalent alpha sorted material.  
When an alpha masked texture is recognized, Trainz will also compress [[texture file]]s using DXT1a compression rather than the DXT3 required for normal alpha blending. This provides a 50% reduction in texture memory usage.


''TBD: Materials which support alpha masking.''
''TBD: Materials which support alpha masking.''
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''TBD: Discussion of using alpha testing without a b&w texture.''
''TBD: Discussion of using alpha testing without a b&w texture.''
''TBD: Overdraw concerns''
''TBD: alpha masking vs mip mapping''


[[Category:Texture mapping]]
[[Category:Texture mapping]]

Revision as of 11:01, 18 October 2017

Alpha masking refers to a special case of alpha blending where all pixels are rendered as either fully opaque (100% alpha) or fully transparent (0% alpha) with no partial transparency. This can be treated as a special case because it does not require alpha sorting in order to produce visually correct results. This provides a significant performance win over an equivalent alpha sorted material.

TBD: Materials which support alpha masking.

TBD: Control of alpha masking via texture.txt file

TBD: Image of alpha mask and the in-game result, versus alpha blending.

TBD: Discussion of using alpha testing without a b&w texture.

TBD: Overdraw concerns

TBD: alpha masking vs mip mapping