Author Topic: Water level vs. terrain Y value  (Read 3167 times)

Offline 3DGuy

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Water level vs. terrain Y value
« on: December 29, 2006, 06:03:46 PM »
Why doesn't these 2 correspond? I've got a terrain and with the mouse I point to a spot thinking that is the level I want the water to be at, I take a note of the Y value and then add a lake object and enter that Y value. Surprise surprise, the water isn't where I want it. I had to move the water way up guessing where it would end up.

Am I misunderstanding the water level setting or am I reading the wrong terrain value.. or is this just a bug?

Offline Irmisato

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Re: Water level vs. terrain Y value
« Reply #1 on: December 29, 2006, 09:25:04 PM »
If the camera is far away, the Y-meters arent so exactly, you have to point three or five places at the same height (or what you think, what's the same), then you come quite nera to the point you expect.
The nearer the camera to the terrain, the exacter you will get the points.

But this is just my personal experience, maybe there is a trick, that I still don't know.

Offline 3DGuy

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Re: Water level vs. terrain Y value
« Reply #2 on: December 29, 2006, 09:35:36 PM »
Here I got right down to the watersurface and close to the wall. I placed the cursor where the + is because the mousepointer doesn't show up with printscreen. See the difference in values  ???

Edit: whoops forgot to show the image :P

Offline Tim O'Donoghue

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Re: Water level vs. terrain Y value
« Reply #3 on: December 30, 2006, 02:42:55 AM »
I've seen the same issue with water. The value entered to get visible water is roughly double the value shown in the preview window. In my case the value showed as 228 meters and I had to enter 538 to get water visible at that level.

Offline Matt

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Re: Water level vs. terrain Y value
« Reply #4 on: January 02, 2007, 09:05:59 PM »
The difference is due to the curvature of the planet. If you look at the X and Z values you will see that you are tens of kilometres away from "ground zero". At these distances, the Y coordinate is no longer the same as the "altitude". The Y coordinate decreases as the surface curves downwards.

If you look at the Y coordinate for the lake centre you will see that is much closer to the value in the preview readout, because the lake centre in your scene is much closer to where your mouse is pointing.

To help in these situations we will need to add an altitude readout, not just X Y Z.

Matt
« Last Edit: January 02, 2007, 09:09:18 PM by Matt »
Just because milk is white doesn't mean that clouds are made of milk.

 

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