Unknown Shadow Error, Static Mesh became Dark..

Hi Everyone…
I hope i have proper shadow map but I have unknown shadow error. When i did “Build Light” first time Everything fine but after few “Build Light” My shadow appearing dark and everything collapse. here with i attache the picture of my Training file…

Hi IRSHATH,

You’ll want to setup a Lightmap UV for your static mesh. You can read more about this error message and setting up a Lightmap UV on this Wiki Lighting Troubleshooting guide here.

Thank you!

Tim

Thank Mr.Tim Hobson

I did uvshadow map already. When I did my uv shadow first time I had good shadow, after that my shadow not good and it getting dark. Please check my other attached pictures…

Thank Mr.Tim Hobson

I did uvshadow map already. When I did my uv shadow first time I had good shadow, after that my shadow not good and it getting dark. Please check my other attached pictures…

Before building light on an object it will default to use Dynamic lighting. Looking at the UV this is not an ideal UV for something like the vase. You are more likely to see seams appearing between chunks that should have smooth contiguous shading.

You’ll also want to make sure that you’re setting the Correct Lightmap Coordinate Index properly. In the image for Test-02 this is the build settings, which does not set the lightmap index. This just will generate the Lightmap UV. If you scroll down in the details panel you will find the Static Mesh Settings tab and you can set the Lightmap Coordinate Index here. By Default it will be set to 0. This can be set to whatever the Lightmap UV channel is, in this case, UV Channel 1.

For Test-03. This is the Moire Pattern. This is a naturally occurring pattern in real life as well. With rendering in an engine and aliasing you can notice the more often as well. Here is a wiki guide to explain the pattern if you’re not too familiar with it.

To reduce something like this you would probably want to use a normal map if using a lower poly mesh and applying a distance detail fade to prevent any aliasing that can happen. If the model is highly detailed there isn’t going to be a way to reduce this. Temporall AA may help reduce, but not completely solve this though.

Thank You very much Mr.Tim…

Thanks Mr.Tim…
Now I got nice Renders

now…