Fox, on 13 December 2014 - 04:20 PM, said:
How do I replace the default translucency tables?
By replacing the default PALETTE.DAT with the one generated by the "Save pal+sh+trans DAT f." menu entry. The help text states that it's a PALETTE.DAT-formatted file that's written. Yes, it contains these three things.
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How do I save it to a file?
The file name is the very first thing that menu function asks you for.
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How do I set a specific value (i.e. first transparency level is 50% alpha)?
First, let's clear up some terminology.
Fox, on 22 July 2014 - 04:08 PM, said:
2 - Can someone upload a Duke 3D palette with additive translucency replacing the default additive (33% and 66%)?
The default one is
alpha blending, "mixing" the color components of the sources like
alpha*SourceColorA + (1 - alpha)*SourceColorB. What you're asking for is
additive blending, like
factor*SourceColorA + SourceColorB. Here, you shouldn't be calling the factor "alpha" any more. From the help text we learn that a range of
numtables blending tables are created, which is a number you are queried for:
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Creates numtables blending tables of smooth additive translucency,
starting with the blending number startbl, with factors for the background color
1/numtables, 2/numtables ... numtables/numtables.
numtables must be a power of two in [1 .. 128].
fullbriOK: should fullbright color indices (>= 240) be permitted as
the blending result of two color indices?
So, if you ask for 8 tables, you get those with factor 1/16, 2/16, ... 8/16. The remaining half is obtained using the reverse translucency bit on the object of question.
Edit: To answer the original specific question, if you create only one additive blending table, it trivially has factor 1/2.
EDIT2: Just to be clear, it's a two-step process. First, you create some blending tables indexed by "blend numbers", installing them with the engine. Next, you write out a PALETTE.DAT containing the desired translucency table -- which may be the original one or a custom, just created one -- and optionally, more blending tables. The latter is an EDuke32 extension for the PALETTE.DAT format.
EDIT3: The old help text for shadexfog.create_additive_trans() had a copy-paste issue, fixed.