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[kukanani]

There are a couple of things I would like to get cleared up.

1) Repeating Textures

     What is the simplest way to do this?


2) Picking

     There does not seem to be any fully implemented way to pick in Xith, besides picking through the screen (mouse).  What if a want to know if my entity has a brick wall in front of him, and my game isn't tile based?  A bit of a harder proposition: what about picking and knowing whether I hit the terrain or not?  That would be helpful to stop a character from just walking up a cliff, for example.

['n ddrylliog]

1) Repeating Textures
What is the simplest way to do this?

IIRC, just use texture coordinates outside the [0-1] bounds, and setting the Boundary mode to "WRAP"
http://xith.org/javadoc/core/org/xith3d/scenegraph/Texture.BoundaryMode.html
http://xith.org/javadoc/core/org/xith3d/scenegraph/Texture.html#setBoundaryModeS(org.xith3d.scenegraph.Texture.BoundaryMode)
http://xith.org/javadoc/core/org/xith3d/scenegraph/Texture.html#setBoundaryModeT(org.xith3d.scenegraph.Texture.BoundaryMode)

2) Picking
     There does not seem to be any fully implemented way to pick in Xith, besides picking through the screen (mouse).  What if a want to know if my entity has a brick wall in front of him, and my game isn't tile based?  A bit of a harder proposition: what about picking and knowing whether I hit the terrain or not?  That would be helpful to stop a character from just walking up a cliff, for example.

Maybe the "really public" API doesn't include this possibility, but the used algorithms can be used for that, of course.. Dig into http://xith.org/javadoc/core/org/xith3d/picking/PickingLibrary.html source code to see how it is done.

In fact what you ask is already implemented : picking from a screen coordinates just need an additionnal preprocessing step : creating a pick-ray from mouse coordinates and the view matrix. Is it correct, Marvin ?

[Marvin Fröhlich]

IIRC, just use texture coordinates outside the [0-1] bounds, and setting the Boundary mode to "WRAP"

Exactly. A value greater than 1 will repeat the texture and smaller than 0 will offset it.

Maybe the "really public" API doesn't include this possibility, but the used algorithms can be used for that, of course.. Dig into http://xith.org/javadoc/core/org/xith3d/picking/PickingLibrary.html source code to see how it is done.

In fact what you ask is already implemented : picking from a screen coordinates just need an additionnal preprocessing step : creating a pick-ray from mouse coordinates and the view matrix. Is it correct, Marvin ?

Yes. You can create an instance of PickRay through one of it's constructors. And maybe you'll want to create a subclass of GeometryPickTester, in which you pick only the parts of a geometry, that you want to be picked. You'll have to attach your KukananiGeometryPickTester instance to the PickingLibrary.

Marvin