show z buffer

[1ctoolfool]

anyone know details of the 'showzbuffer' command, can't find any info in the help files
thanks

[chmillman]

It can be thought of as the inverse of the "Heightfield from bitmap" command. That command takes an image and creates a surface that has its highest point at the lightest value of the image (like white) and its lowest point at the darkest value (like black). Intermediate values in the image (grays) will have intermediate heights on the surface.

ShowZBuffer does the inverse - it makes a black and white image from the different "heights" of (all) the geometry in the viewport (as seen from the camera perspective). The lowest point (furthest away from the camera) is black, the highest point (closest to the camera) is white and other values are various shades of gray...

Beware: the grayscale calculations are based on the viewpoint of the camera and (I think) the automatic clipping planes Rhino uses to define the furthest and nearest points... sometimes it can get confused.

If you want to use this image, you need to export it with ViewportCaptureToFile or ViewportCaptureToClipboard (the second requiring pasting into an image processing program). And if you don't want something to be included in the height calculation, you need to hide it first. --ch

[1ctoolfool]

thanks, how do i set the lighting and the "base" clipping plane to define the lowest surface?
also that 'viewport capture' only gets the image at 72 dpi where i need 600 dpi. right now I'm maxing out my screen resolution and doing a screen capture, any hints are appreciated, thanks much,
jv

[chmillman]

how do i set the lighting and the "base" clipping plane to define the lowest surface

You can't set the lighting. It's not really lighting, just a scale of black to white based on "height". You can't set the clipping planes either, they are automatic. You need to hide any geometry that's outside of the upper and lower limits of what you want to see.

'viewport capture' only gets the image at 72 dpi where i need 600 dpi

First, sorry, the command was ViewCaptureToFile, not Viewport...

Use the "dash" version of the command to access the pixel settings:

Command: -ViewCaptureToFile
Save file name ( Browse ): Filename
View Capture Settings ( Width=1000 Height=600 DrawGrid=Yes DrawWorldAxes=Yes DrawCPlaneAxes=Yes ):

Put the pixel values you want in the width and height settings. Set the grid and axes to on or off as you want. There is no "dpi" setting, these are absolute pixel numbers. --ch