Image prop question

[Cloud Hidden]

Is it true that Send to Surface will set the elevation based on a corner of the prop (bottom left) rather than the center? My prop trees are levitating over the dtm and I have to individually adjust them. It'd be nice if there was a way to mark the point of the prop to use for setting ele.

Second, what's the way to create a new instance of a prop? Say I create a new image prop, which places a copy of the tree on the drawing. Later I erase it. Then I want to use it again, but don't have one to dupe. The prop is in the Textures area of the resource browser, but not in the PIO area. I checked the PIO option when creating it...

Third, the "softness" sliders don't have a labeled scale. Is the left soft and right hard or vica versa? When creating the prop, I encounter 3 different softness sliders: once with the image, then image color (I think), then transparency mask. Do they all do the same or different things? Any redundancy?

Fourth, seems that having anti-aliasing on in photoshop when creating images (trees) hurts rather than helps, be/c it creates a slight off-white halo around the image that survives the transparency mask. Does this sound right? Creating the image with hard edges is the way to go, or is there a better approach?

Thanks...

[ 09-02-2003, 10:12 AM: Message edited by: Cloud Hidden ]

[Dave Donley]

Hello Cloud Hidden:

The props have a 3D locus at the bottom center of the 3D polygon for use as a handle to place them. You could click the loci and drag down to the DTM.

If you choose the Create Image Prop menu item again, it should list existing images in the Choose Image dialog. You can then pick the same image that existed in the prop that was deleted for use in the new one.

The softness increases to the right. Drag the slider to the right to make the antialiasing softer. The softness slider for the image color shader will make the colored pixels blurrier. The one for the mask transparency shader (which you shouldn't see unless you edit the texture resource later) makes the transparency of the mask pixels more blurry. Try creating a texture that has both an image color and mask transparency shader, and render with the Render Bitmap Tool with antialiasing enabled in Custom RW mode at a sufficiently high DPI value. Put the texture on a 3D polygon and view it in perspective projection at an oblique angle. Tweak the image color softness and the mask transparency softness and rerender with the Render Bitmap Tool. You should see the color and mask pixels get sharper and blurrier with changes.

Yes, you are probably better off creating sharp masks in Photoshop. RW should see any alpha channels contained in the image (like for TIFF) so you may be able to create a good blending of the edges by doing that. The edges of the prop mask will have some white in them which will show as a fringe. In the future we will try to match the background colors better to reduce this fringe. For no fringe though create a sharp mask.

HTH,

[Cloud Hidden]

Thanks Dave. I just saw that I created images with the bottom of the image not at the bottom of the file. Doh. I'm posting this progression so that the difference from step to step--VW textures and trees, then imaged grass, then image props--is clearer. Improvement each time. Gotta figure out the best way to clean up the tree at it's bottom left edge, but still, an improvement. Gotta create more interest along the horizon and try the skydome yet. But step-by-step, learning and improving. Had fun yesterday driving all over town getting pix of green stuff. Less fun trying to isolate the green to keep from the background. Getting there.

As always, any ideas welcome.

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W/ skydome 50% sky 75% sun. Overlayed on a background and cleaned up as much as I had time for. Still gotta work on things like shadows going in the same direction and extending shadows to the background from the foreground objects. But certainly getting close enough that I can get by with the products I have for now...VW, Photoshop Elements, and GraphicConverter...

Next challenge....QT Virtual Reality! We gonna see that sometime, Dave?

[ 09-02-2003, 04:23 PM: Message edited by: Cloud Hidden ]

[Dave Donley]

Looks pretty good!

My newest obsession would be image-based illumination, like here:

http://athens.ict.usc.edu/Probes/

The idea would be that you could make a cube of images, create directional lights on the faces of the cube using the pixel colors for the colors and brightnesses of the lights, and get the model to match the (photographic) background. With this you would get the contribution of the trees in your photo, and the grass plane.

I haven't tried it yet but it could be cool.

[MikeB]

quote:

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Originally posted by Dave Donley:

Looks pretty good!

My newest obsession would be image-based illumination

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Is that the same as HDRI. I've seen some discussion of it, and some test renderings on www.renderosity.com in the C4D section. Pretty cool technology.

[Dave Donley]

Yes, the same as HDRI. I now know why those guys would take pictures of chrome spheres on sticks in those "making of" sections of the Star Wars, etc. DVDs.

I'll try to post a RW example of this soon.

[MikeB]

quote:

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Originally posted by Dave Donley:

Yes, the same as HDRI. I now know why those guys would take pictures of chrome spheres on sticks in those "making of" sections of the Star Wars, etc. DVDs.

I'll try to post a RW example of this soon.

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So are you faking HDRI in Renderworks ? If so I'd like to see a tutorial of that