large dem and image rendering in Bryce 5

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#1 YZT_CNG Posted 13 January 2006 - 11:32 AM

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Two Questions:

1. Bryce 5 can render a dem and image at largest size up to 4096×4096 pixels. If the dem is smaller than it, the image and dem will be rendered rightly. But if the dem is larger than it, it will devided into several 4096×4096 squares. They usually probably consist of unused area. When rendered, the image will occupied the whole area, including dem area and unused area, which obviously result in wrong. By the way, every square has different lighting effect. How to solve the question, when dem and image are larger than 4096×4096 pix?

2. I want to render a large area. Then dem is divided into 15 4096×4096 pix tiles. The image is more than 600M. I cannot import it into the picture library. My workstation reads out of ram. But it has two cpus (P4 2.8G) and 3G ram. Why?

#2 Clark Geomatics Posted 10 February 2006 - 02:45 PM

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Two Questions:

1. Bryce 5 can render a dem and image at largest size up to 4096×4096 pixels. If the dem is smaller than it, the image and dem will be rendered rightly. But if the dem is larger than it, it will devided into several 4096×4096 squares. They usually probably consist of unused area. When rendered, the image will occupied the whole area, including dem area and unused area, which obviously result in wrong. By the way, every square has different lighting effect. How to solve the question, when dem and image are larger than 4096×4096 pix?

<{POST_SNAPBACK}>

You should check Tom Patterson's www.shadedrelief.com website - he touches on how to use Bryce for large DEMs... but I don't think he mentions the 'lighting issue'. Good luck.
Cheers,

Jeff Clark
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www.clarkgeomatics.ca

#3 Hans van der Maarel Posted 10 February 2006 - 03:38 PM

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1. Bryce 5 can render a dem and image at largest size up to 4096×4096 pixels. If the dem is smaller than it, the image and dem will be rendered rightly. But if the dem is larger than it, it will devided into several 4096×4096 squares. They usually probably consist of unused area. When rendered, the image will occupied the whole area, including dem area and unused area, which obviously result in wrong. By the way, every square has different lighting effect. How to solve the question, when dem and image are larger than 4096×4096 pix?

<{POST_SNAPBACK}>

Are you using a celestial object for lighting (i.e. a single light source)? I noticed that that usually doesn't work well for larger areas.

Last year I worked on a world-map in VNS (3D visualisation software, like Bryce) and for lighting I didn't use a light source, but rather I increased the intensity of the ambient light. I don't know if Bryce allows you to do that though.

More info on that project and the method I used can be found here
Hans van der Maarel - Cartotalk Editor
Red Geographics

#4 YZT_CNG Posted 11 February 2006 - 11:11 AM

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Thanks Hans and SpatialVisionGroup,

Tom Patterson replied to me a few days before. Bryce really can render large area of dem and image. But you have to divided dem and corresponding image into several square tiles. It's a regret that I still haven't got a better effect. I'm trying still.

In Bryce, I don't usually consider lighting effect, as Tom's website's introduction.