Pixels per m(eter)

I have just been reorganizing my images directories on my PC. (Next part will be my textures folder in SL. *sigh*) I want to draw up some standard pixel ratios for building textures. So that when I use a certain sized texture on a certain sized prim, it doesn't look too stretched or too detailed when compared to building on the whole. The maximum pixel size for a texture is 512 pixels by 512 pixels and the maximum size for the surface of a a prim is 10m. Now, 51 pixels per meter might lose too much detail. (Or I might have just had some bad luck with certain textures.) And for certain complex textures surfaces, you can't tile the image. I am thinking at aiming at trying to maintain 100p to meter ratio. Thoughts?

Pixels per meter is a nonsensical metric. What you should think about is how far away is this object supposed to be viewed?
The default resolution is 1024x768... so 1024x1024 is bigger than a full screen. It also takes up an average of 4 times more disk space and memory than a 512x512.

Dear folks,

The detail of an object, as Eggy had said, is dependant upon the distance it is viewed from. Considering that the texture will be stretched or compressed to fit the object in question, the so-called "resolution" is not going to matter overall. A 1024x1024 texture, if displayed as a full-screen object (by its' very nature impossible in SL, only possible in a graphics viewing program) will of course overfill a 1024x768 screen (which is not always the default, Eggy, as plenty of folk I know operate at 1280x1024 as their default, provided to them by their monitors, without needing to alter the resolution settings. This is particularly of note with flat-panel displays of 17" sizes or greater). If your prim was to fill, thus, 1/4 of the screen, you will be seeing it compressed, and it will look to be lower quality.
Maximum texture resolution supported in SL is 1024x1024, not 512x512, Noel. However, the higher the resolution, the longer it will take to load client-side, even if it does look gorgeous. For most, though by no means all, people, 512x512 textures are difficult in SL to tell apart from 1024x1024, and load 4 times faster. This is perhaps one of the only things to keep in mind when going over your textures. The amount of disc space taken up is something, in my opinion, the Lindens should be worrying about, not us on the client side, since the copy is stored only server-side. Load times, on the other hand, affect everyone.
Just my L$0.02 on the matter.<img>

Yours,
Mika Kyubi (Muromachi)
Kitsune-at-large

Ok, I wanted to get an example (as much good they can do in a screenshot) before replying.

I will use the words texture and images interchangibly. And most of these images are used in interior decorating so they will be seen at distances between 1m to 40m.

For my desktop and most games I use 1600x1200 resolution. However, I know other people probably don't run at that high a resolution and I should keep that in mind when building and texturing.

Texture quality in SL is all over the place. Probably 90% of the textures I have in game are dubious quality. It's a combination of factors such as the color most wood doors don't match the color of any wood paneling or floors, textures that were originally 64x64 pixel images that were just enlargened to 512x512 and repackaged, images that should be able to be used as tiles have such strong light and shadows effects it becomes distracting when the same image is tiled, etc, etc. So you come to the realization that if you want to build a building and keep a consistent texture quality, you have to start make them yourself. And if you are making them yourself, it is very helpful to create a set of artistic guidelines.

Mechanically, there are times when you don't want SL to stretch or compress your image. (Optimistically, we should create the right sized textures for their matching prim, but I doubt many of us have that much time.) For example you are making a wooden fence and it is 15m long. This means it is either made up of two prims either 10m and 5m or two 7.5m or some other combination totaling 15m. There may be times when you can't evenly divide the distance between two prims. In the case of the 10m and 5m prims if you use the same sized image, it will appear either stretched on the 10m prim or compressed on the 5m one. Now, we can simply stretch the image on the 5m prim to match the image on the 10m or tile it twice on the 10m prim to match the 5m prim. However, there are times where the detail on the texture won't allow it be tiled or you don't want to stretch the texture to avoid artifacts (a problem with textures 256 pixels and lower). It's a little more PS work for a more consistent quality in texturing.

The example image is a 402x415 pixel image at 72 pixels per inch. Meaning in RL it would be 5.6" by 5.8" in size. The prims are 1m x 1m x.01m, 2m x 2m x.01m and 4m x 4m x.01m. The first is more than good enough (after the defects in the original image are removed with PS) to be framed and be used as a picture in SL. The second is okay and with the third, the anti-aliasing in the original images is pretty apparent and lowers the overall quality of the image. The larger scale images cannot fill in the missing information for the image as it is simply not in the image. Continuing, this image would look very grainy on a 8m x 8m x.01m prim.

(My original assumption this afternoon was that 100 pixels per meter would be sufficient to maintain a decent level of detail, but that may not be the case. So perhaps we can make a chart that roughly illustrastrates what many of us probably do subconsciously.)

Excuse my badddddd chart making skills.

Level of Detail

64p 128p 256p 512p 1024p

>1m ---- ---- ---- V High - Excessive
1m ---- ---- ---- High - V High
2m ---- ---- ---- Medium - High
4m ---- ---- ---- Low - Medium
8m ---- ---- ---- V Low - Medium
>8m ---- ---- ---- Too Low - Low

(I haven't had a chance to test with all range of prim sizes and textures yet.)

For a base viewing range of x. For every factor of x, shift your results on the chart one column to the right, etc. The farther away you are; the less detail you can see. Thus, you don't have to worry about very detailed images. The simpler your texture is, the move your results to the right as well. Is there a need ever for an all white 1024x1024 texture? No.

*whew*

I am trying to limit myself to 512x512 to be nice to others and I don't want my buildings to look like grey blobs any longer than normal. Plus, I don't think you really need that much larger for building interiors or exteriors for that matter.

And the screenshot that I forgot.