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View Full Version : Objects cut off when camera moves in close?



nikmills
04-05-2004, 09:12 PM
I remember this issue but I can't recall how to fix it. As I move the camera very close to an object and the object clearly passes "into" the lens and gets sliced away. The object still renders, but can't be seen in Layout by the camera.
Someone please remind me how to work up close?
Thanks

mswanson
04-05-2004, 09:21 PM
Press "d" for Display Options and turn off "Fixed Near Clip Distance" (or leave on and decrease the number).

Beamtracer
04-05-2004, 10:22 PM
It's just an Open GL bug, and won't affect the rendered image. There's something said about it in the LW7 manual.

Triple G
04-05-2004, 10:43 PM
Or you can just change your grid size using the bracket keys [ and ].

Scazzino
04-06-2004, 08:34 AM
Yes, just turn off: Fixed Near Clip Distance.

There is also an issue with Fixed Near Clip Distance to be aware of...

If you open a scene that has Fixed Near Clip Distance enabled, and then open a scene that had it disabled... it will remain enabled. Then if you save the second scene, it will be saved with it also enabled...

This is one instance where a setting from one scene can creep into another scene...

So anytime a scene that used to be fine, starts having objects clipped, it could be that you had opened a different scene that had Fixed Near Clip Distance on... and it migrated into your current scene... Go to display prefs and turn it off...

-MikeS

eblu
04-06-2004, 10:10 AM
its not a bug, its a feature.


if you draw straight lines from the point of your camera, that project from the camera, at the four corners of your viewPoint, you get a sort of an endless pyramid, where the camera is the pointy end and the lines go on forever. Computers don't like using the value "infinity" it screws up speadsheets, so a clipping plane was developed. the plane is described by distance from the camera. anything on the wrong side of a clipping plane gets ignored from the render (ie: display and final render).

LW has both a near clipping plane and a far clipping plane. so if your object is not wholly between the clipping planes, it will get "cut". this does not affect geometry, only OpenGL views and renders.

its a little counter intuitive to cope with, but the resoning behind it is sound. using the brackets ([ + ]) you basically change the overall scale of your scene, this effects click n drag speeds, and the relative size of lights and Cameras in your scene.
If youre near clipping plane is cutting through your objects, than you use the brackets to make your camera Smaller, thus bringing the clipping plane closer to the camera, and not cutting your object.
Usually you don't have to worry about the far clipping plane, unless you do lanscapes at real size.

nikmills
04-06-2004, 10:26 AM
thanks all.

comment to eblu: In fact even though the object is clipped it in fact does render (as far as my experiments show)

and a question. These brackets [] you are talking about. Where do I access them? What are they? I'm confused by this part.

And yes my camera is huge and I'd like to make it smaller. Is that a function of grid size or these brackets or what?

These scale factor issues have plagued me forever.

Thanks to everyone

nikmills
04-06-2004, 10:29 AM
Oh I get it bracket KEYS!!!

Okay that's nice, but how do I shrink the camera and lights?

joao
04-06-2004, 11:39 AM
Ok.....
Just press d for display options....
In it, there will be a place where you can set the grid size. Thats the size of every grid square.
The bigger it is... the bigger the Lights and Camera...
The smaller.... the smaller the lights and cam.

If you move in very close to your object with the camera.. than you should use a very very tiny grid size! This will help you see if you're too close or if there is something on the way.

Took me a while to figure it out... and I don't know why the camera size and OGL preview is relative to the grid size but....

It will not change your renders (i don't think). It will only help you position the camera and preview the renders better.

Basically... if you're rendering a huge starfield and planet system... than it makes sense to have a very big grid size... so you can move around more easily.
If you're rendering something more exciting (such as buildings), than it makes sense to have a small one.

cya