## samedi 4 mai 2019

### New version pst-marble 1.6

The new version is available:
Some very spectacular new options were integrated by Aubrey Jaffer within this new version pst-marble 1.6
For colors we have: tint, shade and edgy-color.
RGB $\gamma$ tint
Colors within the system RGB modified by the parameter $\gamma$
$0 < \gamma < 1$ darkens the color; $\gamma > 1$ lightens the color; and $\gamma = 1$ leaves the color unchanged.

RGB $\gamma$ shade
RGB $\zeta$ edgy-color
from the initial color, for $\zeta > 0$ one gets a shading effect of color darkend within the center to lightend near the contour, one gets a bigger effect if $\zeta$ is big. We get the inverted with $\zeta< 0$.
A marbling with edgy-color by Aubrey Jaffer:

$x$ $y$ $\lambda$ $\Omega$ $A_s$ wriggle-shade
We take the first three arguments of "wriggle". Contrary to wriggle, wriggle-shade takes a scaling argument $\Omega$.
$A_s$ is not necessarily equal to $A$ to wriggle.
When $A_s$ is close to zero, the shading will be softer. If $A_s$ is further from zero, the shading will be darker. As with A in the wriggle command, realistic shading requires $|\pi\,A_s|<|\lambda|$|.
When $A/\lambda > 0$ and $\Omega=0$ and $\Omega =$ 0, the darkest rings are at equal rays at odd multiples of   $\lambda$; otherwise, the darker rings are integer multiples of $\lambda$ and there is a dark point at $x, y$.
The difference can be compared between these two papers when applying wriggle-shade.
A simulated nautilus shell on marbled paper with this option:
This option also exists with jiggle-shade.
A new paper option that gives the color to apply to the shadings commands: jiggle-shade or wriggle-shade.
Indicates whether hue (brightening) or shading (darkening)  caused by the movement of paper produced from the jiggle-shade or wriggle-shade commands.

Here a magnificent example proposed by Aubrey Jaffer which he calls Moiré: