surfaces appearing/dissappearing

[dsdsdsdsd]

hello;

I exported a .w3d from LW to Director that has a room with picture frames on the walls;

In Director I applied camera dollies and camera pans (actions) to the 4 arrow keys(triggers);

when I move around the picture frames get very distorted if viewed at an angle - sometimes completely dissappearing;

any thoughts?
thanks
Shannon Burnett
Asheville NC USA

here is the link (http://www.toddanddotty.com/june_gallery)

[digimassa]

:cool:

for me it looks as the distortion comes from a to short focal lenght of your camera and the pictures may disappear as they are to close to the wall or on the wall, so set your camera to longer focal lenght and move the pictures some mm away from the walls.^^

[dsdsdsdsd]

digimassa; thanks for responding;

I will try tinkering with the focal length; good suggestion, thanks;

Shannon Burnett
Asheville NC USA

[mdoyle]

Somtimes it also depends on the graphics card you are using. I found that in shockave and alot of realtime 3d engines if 2 polygons are very close to each other they can overlap or disappear. If u find that some times they "flicker" or are ok as you are close up but flicker or disappear as you move away it is becuase the card is trying to work out which which object to render cos they are so close. For example if u had the picture on the wall and move the camera further away then the wall will show through the picture. The best way to get rid of it is to cut a hole in the wall where the picture hangs to prevent this.

Cheers

Marky

[dsdsdsdsd]

marky, thanks for the reply; your idea sounds good;

many thanks for the suggestion
Shannon Burnett
Asheville NC USA

[digimassa]

:cool:

Hey, this was my idea:D

[dsdsdsdsd]

cutting a hole in the wall worked;

I appreciate your suggestions;

Shannon

[Yarg]

This is probably due to the z-buffer in shockwave 3D - polies on top of each other or worse transparent textures don't get sorted properly and one can appear infront of another. So.. don't do it ;-)

Another thing that's interesting is that the exporter exports all shaders with the transparent property set to true! If you find that you can see through things that are in front of others then make sure your shaders transparent property is set to false. I find it best to run through a repeat and turn all the trans properties in the shaderlist to false and then just turn on the ones i need on startup.

Yarg

[MentalFish]

It is a z-buffer issue and its called z-buffer fighting which will always occur in a 3d engine when the near clipping plane value is very low (it will have problems figuring out what surface is in front due to "borderline" values during calculations). In ShockWave 3D you can set the drawdistance for the camera, where to start (hither) drawing geometry and where to stop (yon) drawing geometry.

member("scene").camera[1].hither = 4

Default is 1 and makes it difficult for the 3D engine to figure out what polygon is on top of the other. With a higher setting for the near clipping plane (hither) the z buffer fighting will still occur, but at a different distance to the object (when camera is further away from it).

Set the hither as high as possible and make sure you dont let the user go to close to the geometry so it disappears (gets clipped).



The issue of transparent textures... ShockWave 3D sort depth on a pr object level, not pr polygon. So when you have transparancy (texture with alpha) applied to a model, ShockWave wont know what polygon is supposed to go on top of another.

Solution:
Explode the polygons into objects by using this plugin:
http://flay.com/GetDetail.cfm?ID=1622
and viola, you can have complex shapes with transparency applied (i.e. trees with groups of leaves).

Tree examples where 1 tree = 2 quadpoly planes (2 seperate objects / layers) with alphamapped texture:
http://rally300.com/forum/trees.html
http://rally300.com/forum/trees2.html

Also, dont use clone, scale, rotation or move in Layout. The exporter does not export it properly. If you just scale an object or just rotate it, its fine, but when you apply a combination of them it mess things up. Its best to set up the whole scene in Modeler, even though your centerpoint in each object wont be centered in the object, but that does not matter much for static objects.

[mdoyle]

Cool thanks for the links. A good bit of info there. But just to let you know that if you set up your scene in modeler and change each objects pivot point to its centre then it will convert to shocwave