Microsoft KB Archive/175821

PRB: 3D Texture Anomalies (swimming) with hrcExplode Effect

PSS ID Number: Q175821 Article last modified on 11-07-1997

IRIX:3.7; WINNT:3.7

IRIX winnt

================================================================ ==

The information in this article applies to:

 Softimage 3D for IRIX, version 3.7 == Softimage 3D for Windows NT, version 3.7 == 

= SYMPTOMS =

When a 3D texture is applied to a model that has an hrcExplode effect, the 3D texture does not remained fixed in one place (swimming effect) on the model’s surface, even though the 3D texture is not animated.

= CAUSE =

The 3D texture’s projection is based on the hrcExplode parent’s center, so when the children of the hierarchy move in different directions, each child receives a different 3D texture pattern as it changes position.

This is similar to a slide projector projecting an image on a moving object. As the object moves through the projection, its surface receives the pattern that is available at that moment (in SI terms at each frame).

= RESOLUTION =

Complete the following steps to create a 2D texture map based on the 3D texture:


 * 1) Apply the 3D texture to a grid.
 * 2) Pan the camera close enough to the grid so that no black background is visible.
 * 3) Render an image with a square resolution (such as 512 X 512 and a pixel ratio of 1.0).
 * 4) Apply the 2D texture map to the Parent in UV mapping projection of the hrcExplode hierarchy.

The children models will receive the texture.

The result is not exactly the same as the 3D texture, but the “swimming” effect no longer occurs.

= STATUS =

This behavior is by design.

= REFERENCES =

If you have any questions concerning the information contained in this article, contact support@softimage.com by e-mail.

= Additional query words: si si3d si3dmat =

Keywords : si si3d si3 Version : IRIX:3.7; WINNT:3.7 Platform : IRIX winnt Issue type : kbprb ============================================================================= Copyright Microsoft Corporation 1997.