View Full Version : Bitmap Node: Object Follows Displaced Surface

10 October 2005, 03:04 AM
Here’s an expression using the new Bitmap node to make a moving object follow the surface of a displaced plane. The node converts greyscale values displacing the plane to Y offset values for the object. The effect can be seen directly in the editor using displaceVIEW.

The object offset will automatically adjust when the Displacement Height or Plane dimensions are changed.

This setup also works with the Relief Object. To do this, replace Displacement Height with the Relief Y size and feed the third Range Mapper’s output straight into the Pos Y port.

The attached 9.1 scene file just needs the Bitmap nodes added as shown in ‘XPresso Editor.jpg’. ‘Noise.jpg’ should be used as the node’s Filename.

10 October 2005, 03:15 AM
Hi Darter,
Until now I thought the Bitmap node was a 9.5 thing :banghead: Even after trying to figure out the latest Expresso challenge :argh:

FWIW those who don't know:
displaceVIEW is part of Jenna which is now free at 3dattack-

10 October 2005, 03:20 AM
Sorry, I should have clarified. The Bitmpap node is new in 9.5. If the attached scene file is loaded into the 9.5 demo or registered version it just needs the Bitmap nodes added for the expression to work.

10 October 2005, 03:24 AM
Oh well. I had high hopes.
The fact that the file opened and I saw something made me happy for a moment.
To much left to learn in 9.1 anyway :D

10 October 2005, 03:26 AM
Very Cool. This should come in handy in tons of situations.

Thanks for sharing,


10 October 2005, 08:06 AM
Hello. I'm trying to make this work, but I get no effect. I inserted the Bitmap node as the picture shows, connected everything, but there is no effect.

After some debugging, I can see the right things being fed into the Bitmap node (the X and Y + filename is set), but the Color output keeps outputting a [0.6,0.6,0.6] vector. I'm guessing the right part of the flow is working as well, so the problem is somewhere in the Bitmap.

I'm doing this on a school mac with a 9.5 version that seems a bit clunky to me ... but I can't reinstall or anything here.

Any ideas?
Thank you for the great XPresso setup anyway!


Forget this, the Mac's are OK. I was just too blind to see that there are TWO bitmap nodes to insert afterwards. After doing exactly what the picture shows, it works.
Just thought I'd leave this here in case anyone else stumbles ... My hint: drink your real espresso before touching xpresso in the morning!


10 October 2005, 08:12 AM
yes I have the same problem.

Rich-Art. :thumbsup:

10 October 2005, 08:21 AM
Thanks to everyone for the feedback.

The vector output problem sounds like only one Bitmap node is connected. Make sure that the Bitmap on the left side of the picture has its Width and Height values connected to the Range Mapper ports. If I disconnect this node, I get a vector output of 0.6,0.6,0.6 from the Color port of the second Bitmap node.

If this doesn't solve the problem, could you post the file?

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10 October 2005, 08:21 AM
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