Help - overkill shadow effects or a lighting bug?

from Sins Forums

Ive imported my own models and textures, thanks a lot to the tutorials on the forum, but now that my ships are in-game and flying around ive noticed that the shadow effects on them are really extreme.

I can increatse the self-illumination of the ship using the -da texture, which brightens things up enough to counteract some of the shadows, but there are still sections that turn dark brown when i rotate the camera. I would have expected the shadows to change when the ship moves relative to the light source, but just moving the camera causes sections of the model to darken abruptly.

Does this sound familiar to anyone?

 

Thanks in advance..

modding
2,078 views 9 replies
Reply #1 from Sins Forums Top

Yes I've also seen some wierdness when rotating the camera. It seems the camera does some form of illumination because it also happens on regular capital ships (just tested this on the Dunov Tech battlecruiser - and even on a dark ambient map (the blue skybox) I get illumination when I rotate around the ship to where the darkest shadows are.

I personally don't like it. I don't think camera angle should influence light maps or sources.

Reply #2 from Sins Forums Top

If the sections of a model suddenly jump from very bright to completely dark, with sharp angles and transitions between light and shadow, you haven't properly set tangents to your model.

Sins of a Solar Empire II
Reply #4 from Sins Forums Top

Also check your normal maps to make sure you Have an alpha channel. If you dont then copy your red color channel in your normal map, and rename it to alpha then resave it. I dont know why the dev's use the red channel, but that is what they told me to use.

Reply #5 from Sins Forums Top

As far as I know, dtx5 compression makes a really lousy job with normal maps, and one way to get around that is to copy the red channel to alpha and tweak the shader to use that - apparently you get improved results with less chunky normal maps.

Also, if you are using Photoshop, DO NOT use NVidia's plugins to compress your .dds textures. Use DDS converter 2 instead - its faster and does a better job. And it can work with Photoshop format and do batch jobs.

That said, I am still curious how Ironclad managed to keep the fine detail in their .dds textures... there's hardly any distortion or pixellation present, something which plagued me since day one and still does to an extent since I use very high detail texturing for my work.

Reply #6 from Sins Forums Top

I dont know.. Since sins 1.02 (when IC switched the shaders for team color, and specular) The normal maps dont stand out like they used to. My modeling friend that i pluggrd sins to asked me why arent there bump maps because he said he could hardly see them at max settings.

That is good info to know about the red channel. Thanks.

Reply #7 from Sins Forums Top

That's strange. I don't usually have a problem with normal maps, but if you are using very subtle detailing, then it may be lost... I think because of the way mip-mapping is used in the engine. As soon as you move away from the ship even a small distance, mip-mapping kicks in and obscures the finer bump mapping and texture detail.

Reply #8 from Sins Forums Top

That is true. I remember the early beta's when i marveled at the kol (the old model and the new), and all of the detail IC managed to cram into it. Perhaps they changed how soon the mips kicked in.

Reply #9 from Sins Forums Top

Ok, i fixed the tangents and made sure the alpha matches the red. It looks way better now, thanks guys!