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Images and bumps and textures
About Truespace Archives
These pages are a copy of the official truespace forums prior to their removal somewhere around 2011.
They are retained here for archive purposes only.
Images and bumps and textures // New Users
Post by chromedragon // Feb 5, 2007, 10:04am
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chromedragon
Total Posts: 33
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Hello,
If I have an image that I want to apply to a surface, but I need a bump map, how do I make a bump map to correspond with this image?
2nd question: Do the words bumps and textures mean the same thing?
:confused: |
Post by spacekdet // Feb 5, 2007, 10:22am
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spacekdet
Total Posts: 1360
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It's not always straightforward as this, but the general idea is:
Open the texture image in your editor, convert to a grayscale image. The dark areas will appear to be indented, and the light areas will appear elevated. You may or may not need to invert the image. Some images work 'out of the box', others need more intense manipulation to get right.
2) No. Textures generally mean they are in the color channel, bumps are in the displacement channel. They 'simulate' actual bumps, dips, lumps, scratches, etc. |
Post by GraySho // Feb 5, 2007, 10:28am
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GraySho
Total Posts: 695
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In the material editor, right click the bump channel, and choose "bump map" from the "displacement shaders" that will open up. Then you can choose a bitmap as bump map.
Any texture bitmap can be used as bumpmap, though only the grayscale will be used. Lighter pixels will be shown as elevations, darker pixels as indents.
A texture can be a combination of shaders, bitmaps, and bumpmaps. A texture map is a bitmap image that is applied to a surface. Though it is commonly called as just texture. A bit confusing :) |
Post by 3dpdk // Feb 5, 2007, 2:39pm
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3dpdk
Total Posts: 212
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Both of the previous post by SpaceKdet and GraySho are correct.
"Texture" in 3D seems to be a catch all word and generally refers to the overall effect of applying color, images, bumps and reflectance to a surface but it can also refer strictly to the image or procedural color used on the surface. "Bump" on the other hand is specific to the addition of the illusion of roughness to the surface with a gray scale image.
Any color image normally used as a surface texture can be used as a bump map. Gray scale images are better to work with because you can easily adjust the contrast between the white and black of the image in an image editing program.
The default for the bump settings will make white the high spots and black will be the depressions, BUT you can reverse this by changing the intensity or Amp (amplitude) to a negative number.
Any color image can be changed to a gray scale image in most image editing software. In Paint Shop Pro, it can be done directly; ie. reduce image to gray scale, or you can de-saturate a color image to 0%. The latter method retains the higher bit level for the image and prevents stair stepping through the gray levels.
By exaggerating the contrast in the gray scale image it can also be used as an alpha map - black is transparent, white is opaque, and gray levels will be semi-transparent, but as with bump maps, a full color image can also be used as an alpha map.
Hope we answered your question.
Paul |
Post by jamesmc // Feb 5, 2007, 2:55pm
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jamesmc
Total Posts: 2566
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Picture is worth a thousand words imo.
They are both the same graphic. First is texture, second is a bump. |
Post by jamesmc // Feb 5, 2007, 3:01pm
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jamesmc
Total Posts: 2566
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And the same graphic texture on bump map. :D
I use Xara Xtreme, which has a bump map plug-in.
It can be done Photoshop, Gimp, Paint Shop Pro etc. |
Post by Steinie // Feb 5, 2007, 3:08pm
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Steinie
Total Posts: 3667
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Your first question "how do I make a bump map to correspond with this image"
If you keep the u repts, V repts, U offset and V offset numbers match for Color and Bump they will correspond with each other. The amp controls amplification. |
Post by Chester Desmond // Feb 6, 2007, 7:28am
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Chester Desmond
Total Posts: 323
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All of the things mentioned so far will work most of the time, but sometimes its not as simple as just turning the image into greyscale. Depending on the image and what you are trying to accomplish you'll often have to hand paint the bump map so the light and dark areas are in the places you want them.
ie:
in jamesmc's example the effect works, but what if you want each colour to be a different height?
Below is a rendered example of using jamesmc's bump map on the left, one I painted in photoshop in the middle and on the right is mine with a negative Amp (as 3dpdk mentioned) |
Post by chromedragon // Feb 14, 2007, 10:52am
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chromedragon
Total Posts: 33
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Ok, good information. Now. I have an object consisting of several objects. What advice do you have on applying texture(s) to the object(s)? |
Post by jamesmc // Feb 14, 2007, 11:39am
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jamesmc
Total Posts: 2566
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in jamesmc's example the effect works, but what if you want each colour to be a different height?
Below is a rendered example of using jamesmc's bump map on the left, one I painted in photoshop in the middle and on the right is mine with a negative Amp (as 3dpdk mentioned)
I still have quite a few options left as you can see from the graphic of the bump generator I use. :) |
Post by jamesmc // Feb 14, 2007, 12:40pm
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jamesmc
Total Posts: 2566
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Once you figure out what kind of bump texture you want, you can move the UV around and experiment. Also, when you render and add lighting the texture and bump will look at little different.
All of the objects in this picture have the same bump texture map I used in a previous post. The difference is I added a layer of color, or an effect from trueSpace such as plastic or metal look. I used the UV tool on the bottom panel to move the texture around (not in the painter.) |
Post by 3dpdk // Feb 14, 2007, 10:13pm
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3dpdk
Total Posts: 212
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Since your overall object is fairly detailed, you're not really going to need a lot of bumping. Usually, actual geometry will provide a lot more flexibility in the final render. You have a lot of geometry here.
Decide the material for each piece of the gun like gun-metal black, burnished steel, reflective steel, maybe a few plastic parts. You will find that it's the reflectance options of the editor that will have more effect in representing the material than texture images or bump maps. Play with the settings for the material you choose for each part until it looks the way you want.
Then upload the image and let us pick it apart from there! ;)
Paul |
Post by Chester Desmond // Feb 15, 2007, 4:43am
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Chester Desmond
Total Posts: 323
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I guess it really depends what kind of detail you want to put on it (and its end use). Like 3dpdk says, for this object you could probably use shaders to get most of the effect you want (ie metal etc). If there are areas where you need to put in hand-drawn details, you should unwrap the UV to get a template to draw on and then apply it as a texture map. |
Post by 3dpdk // Feb 15, 2007, 9:04am
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3dpdk
Total Posts: 212
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Yea I guess I should qualify my answer.
Ordinarily I first attempt to represent a material with procedural textures only, but sometimes this may not work to your satisfaction or if you intend to transport your objects to another program. Usually in that case the procedural textures must be converted to bit maps anyway.
If, lets say, you wanted your gun barrels to have particular scuff marks or something the procedural shaders just can't manage, you will have to hand paint something in an image editor (like Paint Shop Pro or similar ... even PC Paint can produce some pretty decent bit map images.) or use photo textures.
If you decide on the image textures, ask your questions, we'll help you get there. The key here though is not to try to texture the object as a whole. Apply your textures to each separate part (and similar parts) separately, ... and Chester Desmond's tip about using the UV editor can be a time saver. (but can be a little tricky to learn and understand what you are looking at with complex objects.) (but if you learn how to use it , you can be a texture wizard, too!) |
Post by chromedragon // Feb 15, 2007, 9:07am
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chromedragon
Total Posts: 33
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Chester, what do you mean by the following: you should unwrap the UV to get a template to draw on and then apply it as a texture map.?
Another question I have: When you apply a texture, and you apply lighting, will these affect whether the object will have more of a realistic look? I see many many renderings on this webpage, and I am simply in awe as to the realistic look alot of these renderings have. |
Post by chromedragon // Feb 15, 2007, 9:20am
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chromedragon
Total Posts: 33
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People, please forgive my constant questions as some of the combination of words are unknown to me.
3dpdk, what are procedural textures and procedural shaders? |
Post by jamesmc // Feb 15, 2007, 9:34am
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jamesmc
Total Posts: 2566
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People, please forgive my constant questions as some of the combination of words are unknown to me.
3dpdk, what are procedural textures and procedural shaders?
Procedural texture - an image, used as a texture map, generated "on the fly" by a procedure, or algorithm.
This can be some texture supplied by Caligari or one made yourself, but is applied with the procedures of the 3D authoring program.
This is different than applying textures post production. That is, you render the 3D object into an image like "pic.jpg" and then do some touch up in your paint program of choice.
Procedural Shaders I guess would be the same, although adding Shaders in another program that is not 3D, I wouldn't know about. :D |
Post by 3dpdk // Feb 15, 2007, 9:52am
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3dpdk
Total Posts: 212
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In reality there are three main parts to this art; modeling, texturing, and lighting for the final render. and barring the use of a lot of post production editing and effects, a LOT of the final look of your image will depend on the lighting setup.
There's just too many lighting options to say one is better than another; it all depends on the object, the scene and the overall look you want to present. For modeling, a good setup comes in the tS lights library under the name "texture". This is two, non shadowed, white, infinite lights; a strong one from above and one weak one from below. I usually turn on shadows for the strong one above and add one more for backlighting.
This is definitely something you will have to experiment with to get what you are looking for.
(for tips on realistic lighting search the old forums for posts originated by the user "Buzz". I don't know if he's still around but he is most definitely the trueSpace lighting wizard!( with Chris running a close second!!!))
The UV editor is this icon 4333 and here are some tutorials on it's use.
Clinton's texture notes (http://home.mindspring.com/~clintonr/MyTruespace/TS_TextureUVnotes.html)
and
tS6.6 UV Mapping Editor Tutorial (http://reinerstileset.4players.de/TS66_UV_Mapping_Editor_Tut_E.htm)
These may seem a bit daunting at first but stick with it. The trueSpace manual also covers this subject pretty thoroughly.
These are the tS stock procedural textures or shaders (means the same thing)
4334
Open the color window with a left click on the color slide icon (top left most icon); right click inside the color wheel in the "color" window; double click the procedural shader or texture you choose. Each shader will have settings sliders that will change it's overall appearance
... and jamesmc's description may be a bit confusing. A procedural texture is (as he said) a color or combination of colors applied by an algorithm or mathematical procedure. It is not however an image. A lot of these colors are applied using fractal mathematics.
The application of an image as texture is also not done in post production but by clicking on the purple Caligari sample about center in my image and then selecting the image you wish to apply. It will then be rendered with that image as it's surface.
Here's a good tutorial on how to do that (http://www.spacekdet.com/tutorials/ME/)
When I mentioned transporting to a different program I meant something like exporting an aircraft created in tS; when exported to MS Flight Simulator, all the textures and surface detail must be exported not as procedures but as *.dds bit maps. |
Post by Chester Desmond // Feb 15, 2007, 10:42am
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Chester Desmond
Total Posts: 323
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3dpdk's links are the best answer about the UV map question.
It seems that you may be having some confusion about all the terms involved here and some of them are interchangeable and used to mean the same thing.
Without going too in depth, a texture map usually indicates a 2d image painted on to an object whereas a shader is a mathematically calculated surface. A texture map of a brickwall will always look the same (you can repeat it but that is about as far as you can alter its appearance) but a brickwall shader will allow you to change the color and size of the bricks, the color and size of the mortar, the roughness of the bricks and the roughness of the mortar, change the bricks to be squares etcetc.. Both are loaded into the COLOR CHANNEL of the material editor, but have different options and uses. In the picture 3dpdk posted above, the brick wall you see is a color shader..load it into the COLOR CHANNEL and you can manipulate some of its attributes.
Same principle applies with bump maps vs displacement shaders. A bump map is one of many options to use in the displacement channel of the material editor.
Often the overall surface of an object is called it's TEXTURE and includes colour, bump, reflectance and transparency.. this is not the same as a texture map.
A "map" could be used in any program, whereas a "shader" is usually specialized to each program, as james mentioned. What he calls a "procedural texture" I would call a "procedural colour shader" to avoid confusion for myself. Neither one is more correct. |
Post by spacekdet // Feb 15, 2007, 11:36am
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spacekdet
Total Posts: 1360
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Often the overall surface of an object is called it's TEXTURE and includes colour, bump, reflectance and transparency.. this is not the same as a texture map.
I would agree with everything you wrote (and I'm glad you beat me to it) except that it's less confusing to call the overall combination of texture, displacement, and reflectance a 'Material' rather than a texture.
Procedurals are generated mathematically, rather than beginning as a 2D image(such as a jpg or tga file).
One of the great advantages to this is no matter how close your camera gets to a procedural surface, it never gets pixelated or 'falls apart' like a fixed resolution 2D image can.
The disadvantage is that a procedural can be slower to render, since there is more math going on behind the scenes. |
Post by spacekdet // Feb 15, 2007, 11:40am
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spacekdet
Total Posts: 1360
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By the way, here is an example of a procedural program that plugs into tS:
http://www.darksim.com/html/simbiontts.html |
Post by jamesmc // Feb 15, 2007, 12:58pm
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jamesmc
Total Posts: 2566
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good stuff...
It's hard to absorb all this stuff at the beginning. The value of forums and good tutorials are always necessary.
If you build it, they will come. :D |
Post by Chester Desmond // Feb 15, 2007, 4:31pm
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Chester Desmond
Total Posts: 323
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Simbiont is very very cool and FREE.......and if you go to the link for DarkTree itself (same site) there is a really good explanation of what we've been talking about in this thread. I hesitated to post it earlier because they call it "procedural texture" which totally screwed up what I was trying to say :) |
Post by TomG // Feb 16, 2007, 2:43am
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TomG
Total Posts: 3397
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To avoid confusion, a procedural texture / shader is not one that is applied in the 3D program compared to one applied in a 2D program.
A procedural texture or shader uses mathematical formula that take an input (which is the position of the point being shaded) and generate a color (or maybe transparency or bump or shininess etc) based on that input.
The opposite of a procedural texture is using a UV mapped image as a texture (or to control transparency or bump or shininess etc). With this approach, a 2D image is applied to the surface of the object to give it those effects.
Let's just stick with color for now.
The advantage of a procedural is you don't have to unwrap the UV and do all sorts of complex stuff. The "pattern" usually applied pretty automatically and uniformly over the object.
But it will be just a pattern. If you were texturing a shirt, you couldn't add a pocket in there for instance, or a tear, or a stain, or some other specific detail at a specific location. With a machine of some sort, you couldn't add rust or wear at seams and edges, or screw heads at precise places. Since it comes from mathematical formula, it is a repeating pattern and can't have these specific details added at specific points.
This is where UV Mapped textures have an advantage. Since you paint in 2D what goes where, you can indeed paint on a pocket on your shirt and exactly the right place, and you can indeed paint dirt or rust or wear or screw heads at exactly the right places.
BUT you then have to deal with UV Mapping, which is a whole other subject in itself and I would read a lot and search up on tutorials about that.
I will say that the most realistic effects come from using textures and not procedurals, for the very reason that the textures allow precise and unique detail on the surface. A combination can work well (eg layered shader with shiny metal on one layer and a procedural rust shader on the other, with an transparency for the layer using an image, so you can paint where the rust should show up).
So, both procedural and non-procedural textures are in fact calculated in your 3D program. One uses math to come up with the result, one reads from a 2D image to get the result.
HTH!
Tom |
Post by 8-bit // Feb 18, 2007, 12:31pm
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8-bit
Total Posts: 84
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Ive just used the UV Mapping editor to unwrap the object mesh and save it. I painted a texture on it using a paint program but how do I now import the textured mesh back onto the object? |
Post by 8-bit // Feb 18, 2007, 1:30pm
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8-bit
Total Posts: 84
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After much random button pressing etc I managed to both set up an external editor and adjust an object's texture map. Not exactly sure how I did so it would be nice if someone could point me in the direction of a tutorial. :) |
Post by spacekdet // Feb 18, 2007, 1:34pm
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spacekdet
Total Posts: 1360
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How about this one: Here. (http://reinerstileset.4players.de/TS66_UV_Mapping_Editor_Tut_E.htm) |
Post by 8-bit // Feb 19, 2007, 7:15am
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8-bit
Total Posts: 84
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Great, thanks. ;) |
Post by 8-bit // Feb 19, 2007, 10:55am
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8-bit
Total Posts: 84
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I've unwrapped the mesh of an object that I'd like to texture but the resulting mesh is a mess and I can't tell what end is what. Can it be 'unwrapped' in different ways? |
Post by Steinie // Feb 19, 2007, 12:12pm
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Steinie
Total Posts: 3667
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http://www.spacerat.at/tutorials/ts_uvmapping/ts_uvmapping.html
http://forums1.caligari.com/truespace/showthread.php?p=19390#post19390
http://www.render-lab.com/Render-Lab_UV_tut.htm
The first link is not in English but is very good (get the popcorn for the little movie).:) I'm trying to get Graysho to update it. Then there is another link with information about it. Finally there is UV Mapper which is free. They also have Tutorials at their site.
Your question wasn't clear, unwrap what different ways? Programs? Techniques? Unwrapping methods? Planner, Cylinder etc.....
This is one of the more difficult areas of 3D modeling so don't get too frustrated. There are lots of people here to help. Maybe show an object you need unwrapping for suggestions. |
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