Texture Size, Pixel Counts, Video Memory, and File Formats

ive been producing media for more than 25 years not freelance or in a business ive decided to do cause i bought a mac or whatever. Im a full time permenant unionized employee who had to prove his worth with degrees in media before i could even be considered for the jobs. involved in everything from feature motion pictures, award winning web developments, 20 years in educational media. ive been a member of the national association of photoshop professionals for the last ten years. currently im actionscripting for a variety of media within the flash player.

Your facts are correct. even the fact that resolution is not valid inside sl. you are absolutely right.. what your missing is that your talking about INSIDE sl and im talking about preparing files FOR INSIDE sl. if you take 4 pixels of various colours and compress them downsample them to 2 pixels or even one pixel... the colours change. you are telling me that doesnt matter. your telling me i am getting the same image 1024 x 1024 @ 300 dpi as i do at 512 x 512 @ 72 dpi BEFORE i go INSIDE world with it. and that simply isnt true.

Good. Then you should have no trouble understanding what I'm about to explain.



Thank you for finally acknowledging at least that much.



No, what YOU'RE missing is the fact that it's all the same thing. There is nothing different about preparing a texture image for SL than for any other 3D medium in existence.

Once again, dpi is not a part of the texturing process in any way, whether we're talking SL, video games, or Pixar's next masterpiece. A concept such as how many pixels happen to fit into an inch is simply not applicable, end of story. Textures are not for print, so inches do not apply to them. As I've said more times now than I'd care to count, what you should be thinking about is how many pixels are in each image as a whole, not how many pixels would fit in an inch if inches were somehow applicable in this context, which, for the umpteenth time, they're not.

Set your ruler in Photoshop to display pixels, not inches, and you'll be on the right path. Forget all about inches when you're working with textures.


Ask a thousand 3D artists about this, and you'll get the same answer a thousand times. You're attempting to apply rules of print, along with extremely antiquated guidelines of Web design, to a medium in which they have no place. You can either accept that and learn something from all this, or you can go on insisting you're right, focusing on the wrong things, and ultimately wasting your time. The choice is yours.



Yes. But that has nothing to do with how many pixels might fit into an inch. So I'm not sure where you're going with this.



No, I'm not saying that that doesn't matter. I have no idea where you're getting that. What I'm saying is DPI IS IRRELEVANT, and that's all. OF COURSE THE ACTUAL NUMBER OF PIXELS MATTERS. That was never in question.

Once again, what doesn't matter is how many pixels (or dots) would happen to fit into an inch. That only comes into play if and when the image is printed. When it comes to on-screen imagery, inches simply do not exist. Actual pixel count is the only thing that's relevant, not inches, not centimeters, nor any type of measurement. It's pixels and only pixels, nothing more, nothing less.





No, you're grossly misunderstanding. I'm not saying a 1024x1024 and a 512x512 would be the same. Quite obviously, the latter only has one quarter the number of pixels as the former. There's no way they could ever be the same.

What I AM saying is that you can lose the "@ 300 dpi" and "@ 72 dpi" part of it, because those numbers simply don't matter in this context. For texturing purposes, a 1024x1024 at 300 dpi is 100% identical to a 1024x1024 at 72 dpi. And a 512x512 at 300 dpi is likewise identical to a 512x512 at 72 dpi, or a 7 dpi, or 7 million dpi, or whatever other dpi number you'd care to insert. One more time, it's ONLY the number of pixels that is important, NOT the amount of those pixels that might happen to fit into whatever you'd care to define as an inch.

Inches simply are not applicable to textures, period. That is as true in the 2D prep stage as it is within the 3D simulation itself. Again, dpi is simply a piece of metadata that instructs your printer what to do. It has absolutely no direct bearing on the imagery itself.

Where I think you're going wrong in your thinking is that dpi recalculation CAN be used as a means of resizing an image, and it's not uncommon for graphic designers go about it from that direction. Say you've got a print resolution photo at 300 dpi, for example, and you want to resize it to make it suitable for the Web. In that case, you might simply resample the image from 300 to 72 dpi, without ever consciously thinking about the number of pixels.

But that's not the way you should be thinking when you're preparing textures. If you were to hand over that same 300 dpi photo to any professional texture artist, and say, "Please make this into a texure", he's not going to look at the dpi at all, ever. He's simply going to look at the total number of pixels, and then reply, "OK, what you've got here is a 3600x3600 pixel image. The largest allowable texture size I can use here is 1024x1024. So I'm gonna go ahead and down-sample it to that."

Inches would never come into the discussion at all, because once again, INCHES DO NOT EXIST WITHIN THE CONTEXT OF TEXTURING. I don't know how else I can explain this to you. I hope it's starting to sink in by now at least to some degree.

One more time, just to be certain:

FORGET ALL ABOUT DPI! INCHES ARE ABSOLUTELY IRRELEVANT IN THIS CONTEXT! ALL THAT MATTERS IS THE ACTUAL NUMBER OF PIXELS YOUR IMAGES CONTAIN! THAT'S IT!

finally you get some of the question. at the end.

my question was simply...

because photoshop insists you have input in that dpi box if others were using the 150 or 300 that are default in say... chips files... or if they were reducing the file to the 512 512 at 72 before they START the texture or clothing etc or if the designers left the files at their 150 or 300 dpi SETTING ( cause it dont work if you tell the program that its not relevent it wants a number) and compensating by making their lines thicker at the start knowing the down sampling was gonna change it if they changed the pixel count.

was a really simple question of technique. thats all i was asking.

the texturist is also going to explain at that point, that i handed them the image to be textured. that i will lose details based on the downsampling of the image to be texturized and then the texturist will have some tips and hints as to how i can minimize this lost detail.

THATS WHAT IM TALKING ABOUT.

If the texturist didnt explain or offer tips and hints to help theclient keep as much detail as the original. then they are just going through the motions and not being very helpfull to their client. and i would not be taking my work to them.
Peace
some photoguys just use to process the shots and you got whatever they printed .. others tried to get you the best shots with some tweaking and maybe even off you some tips to get the most out of your prints.

SAME deal. im the client that is willing to make sure my files work best for my message, with as little comprimise if it can be helped...

No, Photoshop absolutely does NOT insist that at all. This is where you keep confusing yourself. You don't have to touch that dpi box, ever, if you don't want to. Simply make sure Resample Image is enabled at the bottom of the Image Size dialog, and you'll be able to resize the image via Pixel Dimensions, rather than just by Document Size.

So, if you want to go from 1024x1024 to 512x512, you just type 512 into the width and height fields. Notice, the dpi setting will not change when you do this. This is because dpi is irrelevant for this purpose, as I've said about a thousand times now.

Here's what your Image Size dialog should look like:







No, it doesn't NEED a number. You CAN put one in if you really want to, but you certainly don't have to. Again, enabling Resample Image, and resizing by Pixel Dimensions rather than by Document Size is what you want to do.




The answer to that sort of question is yes, as I said when all this started. But you seem to have overlooked that when you got so bent out of shape over your misunderstanding of the dpi issue. I sincerely hope that you get it now.





Yes.




Good. Then can we now finally please cease all talk of dpi, from here on out? Dpi has absolutely nothing to do with the question you're now asking, and as I keep repeating ad nauseum, has nothing to do with ANYTHING related to texturing.




Uh, OK, but I fail to see what that has to do with the topic of this thread. Didn't you already promise to start new threads for this off-topic stuff?

so ... the answer is 72. as that is the default when photoshop opens. now that you have that str8. stop answering my questions as you take to long to get to the point.

to you saying photoshop doesnt need a number? try putting 0 or leaving it blank. you will get an error dialog and a set of values to choose from or it defaults to the previous working input. you have inadvertantly answered part of my question anyway.

now leave me ask other users.

when you open for example the upper body template by robin wood 2005 vector smart template. its 1024 x 1024 x ok get this and i wish i could make this louder for some ... 150 dpi.

ill ask again... what teqniques are some of you designers and texturists using to keep the designs details detailed when you convert your files to ... duh... the 72 for use in world.

Chosen is right: the DPI is irrelevant for sl. He's really not trying to be the bad guy here, at all. What he is saying is just the truth for texture work in sl.

The only thing that matters for sl is the x/y dimensions of the image.

If you are using a template that is 1024 by 1024 and it says 150 dpi in the box, ignore the dpi box. Really. *You do not need to change it to 72 dpi for upload in sl.* Just adjust the pixel dimensions to 512 by 512, then upload to sl. Just don't change that DPI number when Resampling and you'll be fine.

As for trying to preserve image quality in going from 1024 x 1024 to 512 x 512, Chosen has given some great tips in this and other threads in the texture forum. Namssor Daguerre has also suggested using Bicubic Sharper in certain situations when going from 1024 to 512 (or 512 to 256, etc.).

No, 72 is just the number I happened to have in there at the time I took the screenshot. It could be literally any other number you'd care to insert, and it wouldn't have made any difference at all. The point was simply to show that the number did not change when the image was resized. If I had happened to start with 150, it would have remained 150. If I'd started with 1, it would have stayed 1. If I'd started with 12345, it would have still been 12345. Dpi simply does not factor into this at all.

If you want to change it to 72 from whatever you've got now, go right ahead. It certainly won't hurt anything. It also won't help anything either. It won't make any difference whatsoever, end of story.




Believe me, I'd like nothing better than to stop answering you. But this is a stickied thread. I'm the one who first authored the sticky, and I'm the one who still maintains it. I don't have the option to ignore ANYONE here, unless I want to let the thread lose its value, which I don't.

Now, I'm going to ask you once again, PLEASE start a new thread for your off topic questions, just like every other user of this forum does every single day. Your stubborn insistence on posting here is accomplishing very little, besides demonstrating your utter disregard for the well being of the rest of the community. These stickies exist for very good reason. They perform a vital function, and the only way they can continue to do so is if they each remain mono-topic. Please don't troll them with off-topic posts.

The questions you keep asking over and over and over again are not relevant to the topic of this thread. Take it somewhere else.

If you can't do the right thing for benevolent reasons, then do it for selfish ones. The fact is you'll get a lot more responses in a new thread of your own than in this one. 99.99999% of the people who might answer you are not reading this thread, because they already know what it's about. The last thing anyone would expect is that someone might come in and try to change the topic of a sticky that has been in place for years. Nobody, absolutely nobody, keeps up with all the replies to this thread except me.




I didn't say it doesn't need a number. I said you don't ever need to change the number if you don't want to. You could put 1 in there or 10 or 1000 or 10,000 and the texture would be exactly the same.




If you continue to post in this thread, you're going to get me. If you'd care to do the right thing by starting a new thread of your own, as I've asked you to at least half a dozen times now, I'll be happy to ignore your posts.

Fair warning, though. You'll get the exact same information I've already given you. It will just come from different people. Hopefully you'll believe them.




How many times am I going to have to repeat this before you accept the truth? You DO NOT have to change the dpi to 72. You can leave it at 150, and there will be absolutely no difference. You could also change it to 15, or 27, or 1234, or 4321, or 69 dude, or 42 the meaning of life, or every single other number that Photoshop can accept, and there will still be no difference. DPI IS IRRELEVANT FOR MAKING TEXTURES.

If you don't believe me, why don't you just go ahead and try it? Make ten identical textures, at 10 different dpi settings. Keep the pixel dimensions the same. Just make the dpi different. Upload them to SL, and apply them to 10 cubes. You'll see they'll be EXACTLY the same.

If it makes you feel better, do the experiment a second time, and include resizing in the equation. Resize all the textures from 1024 to 512. Leave one of them with its dpi setting unchanged, and change the other nine to whatever you want. Again, you'll see that they'll be EXACTLY THE SAME as each other. There will be no difference between them whatsoever.

This is not just an SL thing, by the way, and it's certainly not a Chosen Few thing. This is one of the most fundamental principles of texturing. If you were making textures for use in Maya or Max or Lightwave or for any other 3D platform, you'd approach it in exactly the same manner, without regard to dpi in any way, shape, or form. Why you feel the need to keep denying the truth of this, I simply cannot fathom. Wake up already, will you?

Notice, by the way, I'm not the only one telling you this. You might want to ask yourself why that is.


But whatever you do, for the love of all that is decent in the universe, take it to a new thread. To continuing to post in this sticky is to do harm to the community. This will be my last request before I ask a friendly neighborhood Linden to forcibly remove your posts from this thread.

i mustbe the one at fault. i must not be expressing myself or communicating what im trying to get out of it ... cause there's no way there are that many stupid people. my question wasnt a lesson it was a comparative of techniques. Please please remove my posts as i dont want to be involved with this group by no means.

Peace

Hi Zoro, (and everyone else reading this.)

If I'm understanding your correctly, you're asking how people plan images when they know they are going to be downsizing them.

The answer is; different people do it different ways, and I'm going to start a new thread to talk about that, since it really doesn't belong in this sticky.

The whole discussion about dpi, ppi, and inches.. ummm.. wow..

I am Robin Wood. The reason that I have 150 dpi on those texture templates is that I was doing print proofs before I made them. I was printing them out at twice the size they would be in the final, because I don't have very good eyes.

I'm in the habit, in such circumstances, of disabling "Resample Image" and just changing the ppi to 150. Double the size, no math. Then, with "Resample Image" still disabled, I change it back to 300, and I have print size again.

Yeah, there are better and easier ways to do that now, with modern printers, but I'm old, and as I said, it's a habit.

Since ppi is totally meaningless for texture work, I just didn't bother to look at it before I made the templates. If I had, I would have changed it to 72, just to be tidy. But I didn't.

However, I don't think you're really asking about ppi. It sounds to me like you're asking about the downsizing itself; the process of losing more than half the information in the image. You can say that what you're doing is going from 6.827 inches at 150 ppi to 7.11 inches at 72 ppi, if you want to. But that's just confusing, because what really matters is that you're going from 1024 pixels on a side to 512 pixels on a side. (If you check in PS, that's what the pixel dimensions, at the top of the Image Size dialog, are saying.)

If you're a long time graphics pro, it might seem natural to use the former way of talking about it, instead of the later. But since it *is* very confusing, please let's just forget about the ppi.

This is particularly true since it's fairly important that all images are uploaded as powers of two. (2 times 2, times 2, times 2, etc. The 16, 32, 64, 128, 256, 512 etc. sequence.) For highly technical reasons your image will be quite a bit sharper if you do this. Feel free to experiment, by uploading the same image with sides that are some power of two, and sides that aren't, to prove this to yourself. (Not you specifically, Zoro. Everyone reading this.) I did, when I first heard it, because I'm that kind of person. And it's absolutely true. The sides don't have to be equal, but they do have to be powers of two.

So, since we need certain pixel dimensions in order to make things work, and it's annoying (at least for me) to figure out what those pixels come to in inches and ppi, and since it doesn't matter in the least what they DO come to, we just use the pixels, and forget the inches and ppi.

I hope this clears things up.