Painting Textures In Houdini Using "Paint"

[brucegregory]

Since Houdini has a fantastic set of brushes built into the program, and the ability to paint colors and, displacements, it occurs to me that there must be a method for creating a texture map right insid of Houdini, eliminating the need for an external "paint" application.

I haven't worked out the specifics yet, but it seems the method might follow the following procedure:

Use "UVunwrap" or "UVPelt" to create a template mesh for your desired geometry. Save the template as a pic file.

Create a hi resolution grid object and apply the template as a shader with texture map.

Invoke the "Paint" operation and apply color to appropriate areas of the template.

Render at appropriately large size. Save the render as a pic and apply this saved pic to original geometry.

Now, if someone could think about how to create a displacement map or bump map from a geometry displaced model, (displaced by the use of "paint"), then we would have an inclusive texture mapping and advanced displacement system operating all within the domain of Houdini, itself.

Think about it,

Greg Smith

[tallkien]

have you looked at the standalone tools, ipaint, ibumpmap and the like

[brucegregory]

Talkien

I was under the impression that these tools were UNIX only. And I couldn't find a link as to where I might get them. Do they work with Windows XP?

Greg Smith

[tallkien]

hehe, look in $HFS/bin, they're houdini standalone tools. check the standalone tools pdf

Now, if someone could think about how to create a displacement map or bump map from a geometry displaced model, (displaced by the use of "paint"), then we would have an inclusive texture mapping and advanced displacement system operating all within the domain of Houdini, itself.

In a point sop you can shade points black to white depending on their height relative to the objects bounding box extents. Then you'd have to find a way to save this color info as a texture, thats it. Also possible with chops (geometry chop). Not sure why you'd want to go that route though

[tallkien]

not sure how to save Cd as a texture but here goes, anyone have a clue?

disp2col.zip

[deecue]

you could do it through a shader. i ended up creating a simple one in vops (1 parameter, wahoo ). did this so i could do it without any lighting model affecting it (so you get a true representation of your values). I used attrib sop to change Cd to Cf1, and applied the shader to the grid. Have the Cf1 channels referencing your point sop color and it will render them out. Render from top view and you have your map dead on.

disp2col_render.zip

[deecue]

too bad i just realized due to my massive amount in lack of sleep that the only reason that method works is because it's on a grid. And it really isn't saving the cd information as a texture, its just rendering a grid with a referenced shader applied. So if the model had any kind of depth or curvature, it wouldn't work. I suppose if there was a way to unwrap your uv's and somehow render that, it would work tho. i did a test with a sculpted sphere in place of the grid in those last two files. I tried using both a uvunwrap and a uvproject and going to my uv editor viewer and both of these will unwrap the model just fine. But it can't seem to get it to render from that pane.

Any thoughts?

[tallkien]

Ah-hah! The chop method does work on curved surfaces if you append a math chop the geometry chops and make the channels positive

[deecue]

i would like to reopen this thread if anyone would care to look in to it. i really think this could be an interesting way to create displacement maps. If you could sculpt fine detail on your model and then export that as a displacement map to project back on to your clean model, then that could be very useful. Talkien's CHOP network works great (even on curved surfaces after a positive math chop like he said).

All that is needed is a way to export the color information on the model out to a two-dimensional image file to be used a displacement. (hopefully i didn't make that sound like it would be easy..)

Thanks everyone,

Dave

[edward]

Unless I'm misunderstanding what you want, try these threads:

http://odforce.net/forum/index.php?s=22c22...t=ST&f=15&t=723

http://odforce.net/forum/index.php?s=22c22...=ST&f=15&t=1008

[sibarrick]

Well, I have a solution for you, if this link works then you should be able to get an example hip file. This uses real displacements rather than just bump maps

http://www.fourthwall.ndo.co.uk/hips/Displ...ceMap1000.hipnc

Open it up and look in the model object, I've used a low res sphere and a high res sculpted one. At the bottom of the network should be a render op for generating the map. Run this first and then check it worked by looking in the cop2net, (everything is set up to render out to $HIP).

You should then be able to render the low res sphere using mantra1 and it should (fingers crossed look like you rendered the high res sphere)

I'll try and put it all in a HDA so it's a bit easier if I get time

Si

[deecue]

thanks for the links edward. wasn't aware of them. the one was more what i was looking for displacement wise, but i couldnt get his setup to work with a sphere. only a grid.

And your method works great Simon. Way above my head, but still very well done. Good job. I would love to see an hda of that.

thanks guys,

dave