Well, this is an old Thread, but i guess its better i write here, because it seems I have exactly the same problem.
I have no problem with stencil shadows. They run pretty fine in my little test scenes. But with texture modulative shadows I got some "effects" that look very similiar to the ones explained here.
Here is a scene reduced to nothing but one floor plane and one moving spotlight:
http://img274.echo.cx/img274/4963/texshadowsprob5uo.jpg
The spotlight just lit a little part of the area it should and causing a black "blobb" beside it. Additionally, there is a thick black line on the right side moving with the light. (You cant see thi sline very good in the screenshot, but it is easy visible when you would see the light and the line moving).
Here is a scene with the same spotlight and a few simple boxes and a static geometry ground:
http://img274.echo.cx/img274/5337/texsh ... ob20er.jpg
It does not matter if I use Direct3D or OpenGL, windowed or fullscreen mode. I played around a lot with the shadow and light properties (max. distances, shadow and light colors, the light params, texture settings etc etc), but I always got this wrong shadows.
I checked a dotzen times now the shadow-demo with the athene-mesh, the tutorials in the wiki about lighting, I tried differnt scene setting (and at least one without anything but one simple plane and just the spotlight without any other objects or a skybox in it), but i cant seem to find what is causing that problem.
Additionaly, all scenes work pretty well with stencil shadows. Just the texture shadows are causing this problems.
What the little programm basically does is (in this order):
- choosing the render system (for example DirectX9)
- creating the render window
- choosing the scene manager (octree)
- setting the shadow technique
- creating the camera and the viewport
- creating the light and the meshes/plane (I tried different orders here without any change in the results)
While setting the shadow technique, I also tried a lot of different things, from just choosing the shadow type and leaving all other paramters to ogre, or by setting all shadow parameters by myself or just parts of them (and also checked different initialzing orders here).
Does anyone have a clue what could causing this? Or what else I could try? This problem is going to give me a rally headache in the meanwhile (the last 2 days i spent just trying to search for the cause of this bug, without the smallest success, and i am running out of ideas).
I would be very, very glad if anyone could give me a hint here.