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.

No comments: