[LSC] Transparent stickers and color 16

[philohome at free.fr]

Selon Travis Cobbs <tcobbs at gmail.com>:


> On Jan 12, 2008 12:51 PM, Orion Pobursky <orion at ldraw.org> wrote:

>

> > This sounds like a render/implementation problem and not a problem with

> > the spec.  If transparent material isn't displaying correctly then

> > either we need to define a better transparent color or the renderers

> > need to be corrected to better display trans-white.  Unless you can give

> > me concrete and visual examples that this issue is a problem with the

> > spec and not with the renderer, I feel that the use of color 16 in this

> > way is definitely non-standard, confusing, and should be avoided.

> >

>

> Due to the physics of the situation, the transparent part of stickers comes

> out looking (almost) like it's not there at all when you stick it to a

> surface.  There are two main reasons for this.  First of all, the stickers

> are really thin.  Secondly, they're stuck firmly to the brick, with no air

> gap behind them.  If you take a piece of clear LEGO, and put it right next

> to another brick and look through it to the other brick, I don't think the

> transparent LEGO will disappear in the same way that the transparent part of

> a sticker disappears.

>

> Because of this, I don't feel that it's a renderer issue.  The two materials

> really do have fundamentally different properties, and we don't currently

> have a way to model a clear sticker's properties in LDraw.

>

> There's also a question of pragmatism.  If stickers look good using this

> method, and can't be made to look good in any existing renderers using any

> other method, the users of the LDraw library are going to want us to use

> this method.

>

I completely agree with Travis physical analysis. Maybe the issue could be
solved also with the definition of a new very transparent (high alpha) color,
but imho it would be even more confusing and for sure would cause many
compatibility problems with older LDraw software packages.

Philo