Why does Ambient Occlusion in Houdini do this?!

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Ah cool, yeah I knew how t turn on the primitive normals display but not point normals. So if I put down a facet and activate pre-compute normals the point normals will display when I turn the prmitive normal display on?
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No, when you turn on point normal display.
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oh they're seperate buttons, I thought you meant Houdini wouldn't display them until you turn on the option in the facet SOP and turn on primitive normals…

Thanks for your help.
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Hello,


wonderfull threat here with great tips!

Is it possible to post a hip file , demonstrating rendering with Ambient Occlussion ? (set up with simple object)
I don't find any tutorial about it.


Many thanks,


bern
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Hi Bernard,

Here's a tutorial from the 8.0 online help:

hdox/houdini/content/base/fm_09_guide_lighting_1013748.xml

Cheers!
steven
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The link seems to be broken…at least on my PC…..

It's really easy to set-up…just create a ‘Vex global illumination’ shader and set it as one of your scene lights ‘SHOP Light’ under the illumination tab. Thats it! Tweak the GI shaders samples parameter to alter quality….
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The link is for the Houdini documentation. Copy and paste it into Houdini's help browser.

hdox/houdini/content/base/tutorials/fm_09_guide_lighting_1013748.html
if(coffees<2,round(float),float)
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Oh yeah…I knew that…. ops:

Still..my help browser doesn't seem able to find the page?
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Seems to work on Houdini 8.1

Just go to the main help page, then go to Tutorials and then Lighting Tutorials.
if(coffees<2,round(float),float)
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I find that with polymodeling I like to bevel the edges instead of faceting the points. In real life there are very few “straight” edges and even the slightest bevel on an edge gives a nice definition that empasizes the 3D nature of the object. Usually you need a poly bevel with at least one division to make this work effectively. Bevels also work well if you are using subdivision surface rendering.
Robert Magee
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When I model these days, I share points as I go. I then build sharpish edges by bevelling them, sometimes with PolyBevel, sometimes PolyExtrude, sometimes just cutting in with PolySplits.
Take a look at Mario's boxes in his hip files for the glass wip on Od force:

http://odforce.net/forum/index.php?showtopic=4196&hl= [odforce.net]

All nicely bevelled edges and render nice, crisp and well behaved.

Aren't those razor sharp unshared edges too CG these days?

Ultimately you need to build the edges proper with poly detail so that you can render with subd's and with GI.
There's at least one school like the old school!
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The PolyBevel SOP is my best friend. But it should be noted that sometimes if you receive a 5,000,000 polygon object to work with going through and beveling everything can be a year long project. In cases like this the Facet SOP with Cusp Polygons can help save the day.
if(coffees<2,round(float),float)
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It's often important to add an extra span outside of the polybevel result or you'll end up with normals being interpolated across what you'd expect to be a flat surface. I usually use a polybevel set to “corner” followed by another polybevel set to one of the round options in order to get around this.
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