[blender] Anyone else noticed differences between renders in 2.49 and 2.5x?

[The Hood]

Calling all other blender people:  anyone else noticed some strange effects when trying to render old models in blender 2.5x?  I've just been trying to update some pak128.Britain images using models from old blender 2.49 files and I get different results in blender 2.5x - very frustrating especially as I'm loving Zeno's new automated render script for blender 2.5x!  If you have noticed - does anyone know how to resolve?

Spot the difference...

[vilvoh]

Maybe you have to adjust some rendering parameters, light related perhaps? I mean, there are big, really big changes between 2.49 and 2.5.x, so probably the rendering process and output is one of them.

[Zeno]

That's true. I've noticed my 2.5 renders are darker and not so clean as 2.49 ones. I don't know yet why, but I'll have plenty of free time to dig into it during the next week. I'll let you know what I can find out.

very frustrating especially as I'm loving Zeno's new automated render script for blender 2.5x!

It's hard to get back to the old manual slow method... I know! heheh

[The Hood]

I've had a bit of a play.  It seems that surfaces with the "set smooth" property are generally worst affected.  Not sure how to fix, other than not to use smoothing!

[Djohaal]

I don't know what is the name of the tool in blender, but you must set normal groups on a per-face basis. The shading and cornering in the first image is due to normals bending over the corner of the box shape, perturbing the light display.

For more info take a look at shading models such as phong. http://en.wikipedia.org/wiki/Phong_shading

[vilvoh]

If I remember correctly, when the surface has been set as smooth, you have to recalculate the normals, pressing CTRL+N or splitting the surface into smaller parts, to reduce the amount of vertex affected by the smooth modifier.

[jamespetts]

Have you tried with the latest stable of Blender, 2.57? Incidentally, I'd say that the 2.5x render is the better of the two.

[The Hood]

Same in 2.57.  If you get them in game, you will soon see the 2.5x version is not appropriate for simutrans - the grey-white shading on each carriage just looks very odd indeed.

Anyway, for the scale of the models at 128x128 tile size, it's perfectly fine to render flat surfaces rather than smooth.  I tried a bit in 249 and you can barely notice the difference.

[jamespetts]

Recalculating the normals just makes things worse, alas, as one gets inconsistent patterns of light and dark. Selecting "flip normals" works to give a stable overall dark roof, but then the results are darker than the roof images from 2.49 (but much closer to the colour actually seen in the 3D viewport in Blender). Selecting all the faces and setting "shade flat" produces a stably light roof, but the appearance is a little lighter than in 2.49, I think.