Why do soften and smear darken my textures ?


I have created a texture entirely in blender 2.47 using UV-unwrapping and applying 2D images to different parts of my UV-map. After consolidating into one image and baking (textures only), i saved the resulting texture as .png image to my disk.

Now in the final post processing step i want take care of the still remaining visible texturizing borders (seams) directly on the texture in the UV-image editor, by using soften, smear and the air-brush.

So i go to texture paint mode, select display mode textured and then go to the edit button panel, where i find the relevant settings in the paint-tab.

But i constantly fall into a weird problem: As soon as i start smoothing (yes, the airbrush is deselected), the texture gets darker and darker. well it also gets smoother, but the darkening is much more visible, than the smoothing. The same happens, when i select the smear tool. And the air-brush does not colorise, but also darkens the image… at the end i get one ugly looking plane colored area ;-(

So something very basic must go wrong. What do i miss here , what could cause this effect ?

Another maybe related problem is: When i hit the border of 2 faces, which sit on oposite sides of the texture image (thus i hit the seam), smoothing (well, darkening…) does not happen across the seam border. So applying the soften brush makes my seam to get seen better and better, instead of getting hidden ;-( Is that intended ?
I would expect, that my smoothing would perfectly swap over to the other side of my texture image, so that i can perfectly improve or hide the seams …

Maybe try using the clone paint, and reload another instance of your uvmap png as the clone source - you could then offset it and 'paint ’ the edges proximal to your seams with adjacent pixels. The only thing i haven’t gotten from the clone tool in the uv image editor paint is how to rotate the clone source - but if you are working on your existing image to clone from itself, it shouldn’t really be a problem.

edit: the darkening could be dependent on the mix mode of your brush? like mix, add, darkend, multiply all have different effects… shooting in the dark here.

Hey, thank you for your response :wink:

Ah, that is an interesting hint. I will try this out and play with it :wink:

No, it must be something different. I tried all of them. They all make quite some radical changes on my texture, but none of them works as expected together with smooth and smear.

We (the machinimatrix team) have just published a video-tutorial, where you can see what i mean… (see: http://blog.machinimatrix.org/2008/09/01/texturizing-with-multiple-images/ ) well i tried to hide the problem (the tutorial is not about how to ruin your texture :wink: ), therefore i made the brush intensity very low, but if you watch carefully (best would be to download the high quality version of the tutorial to see the effect), you see, that indeed the texture gets worse, instead of better. What i exactly refer too, can be seen within the last minute of the tutorial where we try to “enhance the artificial seems” in the baked texture by applying the smooth brush to the texture (and unwantedly leave some dark trails on the surface).

So if you (or some other curious soul) could take a look on what i do exactly… maybe that could solve the problem (ermm… apologize, the high quality of the video is 70 MByte in size)

I had one thought - when choosing to paint on the final texture seams, possibly it would be easier to just sample a color from your texture and paint in low opacity to get a cover on the seam. It might help with your smooth and smear, since it will introduce pure color into the shaded area that actually has dark pixels - moving them around just spreads the dark area.