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sphere-group / pegasus

The Pegasus API for Sphere 2.0
BSD 2-Clause "Simplified" License
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Using floating point units for colors, or chars. #4

Closed joskuijpers closed 10 years ago

joskuijpers commented 10 years ago

The Sphere 1.5/1.6 colors are created using CreateColor(255,....). It uses ranges of 0 to 255: a char. That is very useful because 4 of those chars together form a color for the GPU. And storage of a full color is then the same size as 1 float. However, using floats ranging 0.0 to 1.0 has some advantages when doing math and has more precision. Even tho 0.5 gets converted to 127, it has purpose when doing more math. 255/2*2 = 254.

What shall we do? It seems we can't have both in a reasonable way, as 1/255 and 1/1.0 overlap and we don't have types.

Radnen commented 10 years ago

I'd say stick to 0-255 ranges, most game API's do that. However, I have seen like in CSS for example a setup that has RGB 0-255 but alpha at 0.0 - 1.0

joskuijpers commented 10 years ago

Then I would agree to use 0-255 for colors. I might make a module to add Colorf class that has floating point colors to JS.