| | | | |
| |
| > In lugnet.cad.mlcad, Michael Lachmann wrote:
> > I thought the LDraw group doesn't allow any other colors than the standard
> > ones?
In lugnet.cad.mlcad, Travis Cobbs wrote:
> As it happens, the LSC has been dealing with this very issue for the past few
> months. There is no mention made of dither colors in any of the current LDraw
> specs (including the official parts restrictions). They somehow got dropped
> (accidentally) from the LDraw 1.0 spec (they were in the LDraw 0.27 spec). I
> know that they were dropped accidentally because I was a member of the LSC that
> ratified the LDraw 1.0 spec, and "dither" and "dithered" were never once
> mentioned in the discussions that ratified that.
I've been surprised by some of this discussion of dithered colors, because when
Foundry was created (not by me), it was done as a "clean room" project, based
entirely off of specs, so it's the closest thing out there to a reference
parser, and it's always supported the colors.
Now that you mentioned this, Travis, I recall that we did hit this roadblock and
noticed that missing piece of the puzzle. If I recall correctly, LDView code
was used as our reference on how to handle things. When that appeared to have a
few puzzling questions, we went to some of the specs around (as I recall)
ldlite, and used the various approaches that seemed most in common to codify how
to handle colors.
In addition, I asked that it support alphanumeric color names from ldconfig.ldr,
especially in its user interface, but also in code because we needed that for
the OBI project.
-- joshuaD
| | | | | | | | | | | | | In lugnet.cad.mlcad, Joshua Delahunty wrote:
> Now that you mentioned this, Travis, I recall that we did hit this roadblock and
> noticed that missing piece of the puzzle. If I recall correctly, LDView code
> was used as our reference on how to handle things. When that appeared to have a
> few puzzling questions, we went to some of the specs around (as I recall)
> ldlite, and used the various approaches that seemed most in common to codify how
> to handle colors.
LDView's blending code was originally written to handle LDLite's 0 COLOR syntax,
since that is what was originally used in LDConfig.ldr. LDLite's syntax allows
for the dithering of two arbitrary colors, either or both of which can
themselves be transparent (although I'm not sure that was intentional). So
LDView's blend code pays attention to the alpha value of both incoming colors.
This is unnecessary for the original LDraw.exe "dither" colors, and is also
unnecessary for 0 !COLOUR colors.
--Travis
| | | | | | |