Alpha channel in RayShade

[Roger H. <rog...@mi...>]

I need to change RayShade to support the alpha channel.

Currently each pixel is encoded as four floats, r,g,b and alpha. This  
is then converted to three bytes when the alpha is thrown away. This  
is then converted back to the representation desired by the  
application and O.S. . I can do it three different ways, by making  
the internal buffer always four bytes, or always four floats, or by  
looking at the output representation and using either three or four  
bytes as appropriate. For simplicity, I favour the four byte  
approach, though at the cost of a larger buffer, but then RAM is now  
fairly cheap.

Your thoughts please.

Roger.