Mesh strange behavior

[vybeimvu]

Hello, I'm new to meshing on SL, although i have made meshes on other platforms. I have made some furniture but what happend just now hasnt occured to me yet.

When moving around the mesh some parts seem to dissapear or behave strangely.





Here's the model inside 3DS Max:



 

The mesh was exported to .dae with default settings (like i said it didnt happen to the other meshes)

It has 3 diffuse, normal and specular maps.

 

Any solutions or guidence in why this happens would be appreciated :)

 

Edit: Without the normal & specular maps the biggest problem is gone, but there is still some minor behavior, i've checked inside 3ds max if the (polygon) normals were flipped that was not the case.



[arton Rotaru]

Make sure your diffuse textures doesn't contain an alpha channel when you don't need transparency. To check that the alpha channel is the issue, set the diffuse maps to None in the Alpha mode drop down menu. (Only selectable if the texture has an alpha channel.) If there is an alpha channel on purpose in your diffuse maps, set the alpha mode to Masking and adjust the Mask cutoff, to avoid the sorting glitch.

If you don't need transparency, upload diffuse textures without an alpha channel rather than just setting them to alpha mode None. They will have a smaller memory footprint.

 

[vybeimvu]

Thanks this fixed it i forgot that my diffuse has a black background, didnt know that would pick up as transperant on the diffuse, it was set to "Alpha Blending" i changed it to  "Alpha Masking" now it looks fine, thanks

[arton Rotaru]

A black background doesn't pick up as alpha. I guess you saved out your maps as PNG from Photoshop. PS handling of the PNG format is rather poor. it can add an alpha channel on it's own, even if there is none listed under channels. I prefer the targa format because of that. It's easier to handle in PS.

[ChinRey]

---

arton Rotaru wrote:

A black background doesn't pick up as alpha. I guess you saved out your maps as PNG from Photoshop. PS handling of the PNG format is rather poor. it can add an alpha channel on it's own, even if there is none listed under channels.

---

Gimp has the same issue. It adds an alpha channel to a png by default and you have to remember to remove it manually.

With Paint.net you get to choose when you save but the option descriptions aren't very clear to everybody: "24 bit" is without, "32 bit" is with alpha.

[Christhiana]

Even though your problem is fixed now I would still recommend reuploading your textures without alpha channel since this will noticably reduce their filesize making them load faster and put less strain on your system.

[vybeimvu]

Alright, well my system can handle it but maybe others won't. everything or just the diffuse? However, the diffuse are Vray baked textures from 3DS Max to targa only the normal and specular are png

[Christhiana]

It's just good practise that when you're not using the alpha channel to remove it from your textures. This goes for diffuse as well as normal and specular maps. Targa can have an alpha channel as well. After upload the image gets converted to jpeg2000 with or without alpha channel. Texture memory in SL is limited so every bit helps.

[vybeimvu]

Okay thank you, will do some research

[arton Rotaru]

Supported texture sizes and their memory consumption:
http://wiki.secondlife.com/wiki/Texture_sizes

Channel encoding of the various map types:
http://wiki.secondlife.com/wiki/Material_Data#Texture_Channel_Encoding

Alpha modes:
http://wiki.secondlife.com/wiki/Alpha_Modes_Do's_and_Don'ts