Tuesday, September 2, 2008

Copy Stamp Play


some copy stamping.

the scale and rotation (mostly in Y) is randomized based on $PT.
I used the fit01 expression to fit my random values into a desirable range.

in the first pic, the cards are just planes, but in the second, the cards are 3D with a slight bevel, and some noise (offset for each card through stamping)

to get the Houdini logo - i made sure 'use Template Attributes was on.'
so the Cd att. (color) was copied from the grid (the template) to the cards.
In my shader - i told it to use a Cd parameter and wired this into the colour so the colour info was piped through to the shader as well.

In my current version - i decided to animate the swirl feature of the logo into appearance. In the top view i made a rough poly curve /line that matched the spiral using my grid (with the texture's colours transferred to its points)
as a template.

I then gave it white point colours and animated a sphere along it, then transferred the color to the cards. For the sphere to leave a permanent trail behind it I used a trail sop....thus the cards are animated to turn white.

One issue i had with this attribute transfer - was that because the sphere with the white points is animated - and the grid/ ground plane is of finite resolution - the distance from the spheres points and the grids points changes as the sphere moves around - giving a flickering effect on the white. - The attribute transfer's distance is constantly changing as the spheres points move closer to and further away from the points on the grid.

To get around this - Rob suggested using a group. This was n easy solution - the sphere with trails - intersects the points on the grid (or the points scattered on the grid) and adds them to the group. This group then controls which points have their point colours changed.