knife slash effect?
Toobis
Posts: 990
in The Commons
I am wanting to do a knife slash effect on a shirt or pants but don't know how to go about doing this or know if it even can be done. I basically want there to be a longish circular thin hole where something has cut it where you could see the flesh under the top (the cut I will add in post work) but can this be done? please tell me how.
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Not that hard. Make an opacity (3DL) or cutout (IRay) map, using the outfit template as a guide. A flattened oval cut 'shape' where you want it, black and white -- black is where the clothing becomes transparent.
sorry I really need a guide with images.
This may help:
http://hubpages.com/art/How-to-Make-Custom-MATs-for-DAZ-Studio
As Will says, you will need to edit the Cutout Opacity instead if you are using iray.
Also - its possible that the item which you are editing wont have a transparency map. In that case, start with a white image and use the other imagesof the UV (Diffuse for example) as a guide to where to place the black that will make your cut transparent.
No I am sorry I am still very confused. Does anyone know a more step by step simple way of explaining how to do this? I am not using anything to do with Iray by the way. (sorry for the late reply)
I did what you're wanting to do a bit ago...I'll try to put together some pictures for you...
OK, I'll try to explain...
To start off, you need to understand what the different kinds of maps do. For my thing, I used Diffuse Maps (provides the picture), Opacity Maps (hides stuff), and normal Maps (gives depth and texture).
Knowing an image editor like Photoshop is also usefual.
Alright, The Battle Damaged picture is what you're aiming for in some way (pic 1)
The Regular outfit (pic 2) is what I started with.
The Regular outfit uses (from pic 3) the Diffuse map and the Regular Normal Map.
To make it battle damaged, I changed the Regular Normal Map to the Battle Damaged normal Map, and added the Opacity Map.
On the right side of Pic 3, you can see the outfit with JUST the battle damaged Normal Map, and not the Opacity Map.
I MADE THESE by setting up a multi layered Photoshop File (middle of Pic 3).
On a seperate layer, I drew (using various brushes) the tears in black. I saved those tears on a white backgroun to make the Opacity Map. I saved them against the normal map to make the Battle Damaged Normal Map.
(You'll see in the Photoshop Layers a folder titled "Wounds". I made various maps to apply to a Geoshell that puts bruises and welts on her skin where the rips are (pic 4))
Hope this gives you an idea..feel free to ask questions.
K thanks for the detailed guide but yes I have a few questions please excuse my slowness. All this is from where? I mean I assume I find these textures from inside the daz studio folder for this installed product. Basically I am trying to apply cuts to this top; https://www.renderosity.com/mod/bcs/?ViewProduct=106485 these are the textures I found in the texture file for this when I installed it (pictured) which ones out of these would I need to pick and modify I am not sure here what ones are the diffuse map or opacity map.
You need to load up the outfit and look in it's surfaces panel to see which file is used for which.
In the method I described, you don't need to change the diffuse (though if you were doing like a gun blast or burn or like a light saber slash, you might want to add scroching to the diffuse).
It's very possible there isn't an opacity map already...clothes only generaly have them if they have holes/cut outs/etc. You make one like I i instructed above...load the diffuse map, paint the slashes on a new layer, save that layer over a white background (opacity maps are shades of grey....white you see the outfit parts, black you don't, grey's vary the level of transparency.). You might have to do this a lot of times while you figure out the position you want it in/how it looks on the 3d outfit.
The steps for doing this are simple, but this isn't an easy thing to do..gonna take trial and error :)
Ok I am not up on all this you must understand I am not up on a lot of this stuff even considered basic by many. So I am going to have to do it step by step (sorry)
I loaded it up I don't get how you find which surface is which from this.
Hi Toobis,
I am at work and am on my phone so briefly to get you started.... I can't see your surfaces Panel so let's get that showing.
To the right of the Content icon/pictures (on the left of the screen) there are three tabs showing Scene, Environment and Content Library. Right click on the grey bit below that, and you should see a list of all the panels that you could slot in there. Click on 'Surfaces' and the new tab should be added.
Open it and keep the surface selected and you will see all of the parameters that define how the surface is displayed on a render. You should find amongst these the Diffuse and Opacity Map that has been referred to above.
If if you click on the little image on the left of the parameter (on the right there should be a colour selector) you will get a menu that mainly shows all the images in use in your scene. At the top there should be a Browse option. Select that on an item that has an image loaded and it will open a file open pane pointing at the folder the map is kept in. Copy the path from the top and use that to locate the maps in your file structure.
Hope that helps, as I say trying to type on my phone so apologies for any weird word substitutions.
Yes I was with you until that part. I think a picture would work best here you think you could do that when you are not busy? I would appreciate it a lot. Thanks so far.
If you don't want to muck around in materials and all that, why not render with and without the clothing, and do the rip in post as well as the cut? Put the clothed version on the top layer, and paint a mask that will reveal the skin underneath.
delete.
Images attached.
In the Surfaces pane you should see something like what I have in the Surface Parameters screen cap. This is a list of the various parameters that can be edited to alter the way a surface works.
The top item in the image is the Diffuse parameter. The red circle indicates a mini thumbnail for the image that is currently loaded into the diffuse channel. If you left click on this you should see a menu pop up as seen in the second image (Image Menu). Most of this lists the various image files you have attached to surfaces in the scene. The top four items are different, the top one is of interest here. Click on that one (Browse), it will open a file select menu starting in the folder where the current image is stored. If you copy the path out of the bar at the top and paste it into the path bar in a Windows Explorer window (or a MacOS Finder or whatever) it will take you to where the images are stored. From there you can open them in Photo Shop/GIMP/Paint/whatever and edit them.
Near the bottom of the Parameters image you will see the Opacity map. Note that in this case there is no image loaded into this channel, as indicated by the arrow symbol highlighted by the green circle. This will most likely be the case when you look at the item you are working with.
This means you will need to create an Opacity map. Create it in the same folder you found above. An Opacity map is a grayscale image where white will be opaque and black will be transparent. Start with a white image, then add black to make parts transparent You can use any of the existing maps as a guide as to where on the white image to put your transparent bits. ensure your Opacity map is the same size as the other maps the item uses or things can get confusing.
To use your new Opacity mp, in the surfaces pane, click on the down arrow/empty file marker on the Opacity attribute(as indicated by the green circle), select browse as above and select your new Opacity map.
A good way to create a new Opacity map would be to copy another map and use that as a base. To start make anything that is part of the garment white and the rest black. then editing is easy - just have a play with dotting diferent black shapes around it and see which bits of the garment end up transparent. Once ready, you can add the black crescent into the right spot.
Have Fun!
K before I get into this more ...which do you think is the best method? the postwork method you mentioned at a couple of posts ago or this method?
Either works.
It was TheKD who suggested it in fact. Some people prefer postwork, some prefer to do in in the render. I would suggest trying both and see what works best for you.
It might help if you give some info on what level of stuff you know.
The stuff I talked about involves knowing how to look at the Surfaces Panel. If it's not in your interface by default, then Bring it up under Window -> Panes (Tabs) -> Surfaces
Do you know how to use a multi layer image editor like Photoshop or Gimp?
K sorry I have not replied sooner on all this but have been busyier lately but yes I am trying to do this still and have not forgotten about it. Now I have to backtrack and find the enlargened images of the examples since the small server mishap. Ok Yes I am with you so far but I am a little confused at how to make an opacity map do you think you could make one for me in this example to show me exactly what you mean because learning from example is always better for me. Would you be able to make a quick one for me for the sexytop3 I am using? then I can see how its done a lot easier.
To answer Scavenger; yeh I basically use gimp.
I can't make a map for you because I don't have the product.
HERE is the best I can do.
Picture 1 is YOUR folder of the maps for your shirt. Look thru them and find the one that gives you the best template to work on....you want it to the outline of the shirt so you know where to draw your slashes. I chose the one I circled, it looks to be the best, but that's a guess. You will need to figure it out. The pictures called "color" are likely the diffuse maps. Some diffuse maps are just solid tiles like that, some show the shape (such as in my superhero costume above). Just find the one that will work the best.
Take that one and MAKE A COPY OF THE FILE. Best to work on a copy just to avoid messing up the original. Open that copy in photoshop/gimp.
You will then add two layers to the image. a Solid white one, and one you will leave empty. HIDE the white one so you see the background picture. Draw your cuts in black. UNHIDE the white layer, and merge the White Layer and the layer with the black marks and save it as a png or jpg. You'll have an image that looks like the "finished opacity map" in pic 2.
Load that in, Daz, into the opacity channel of the shirt. you should see the empty spot in the shirt. Do a quick render so you can see what it's looking like in rendered form.
Do this in a simple form, simple black marks, so you get the idea down. then get more complex, making the slash marks look better, using greys to vary the ammount of transparancy.
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WHAT I WOULD ACTUALLY RECOMEND is to NOT try to learn these concepts on the shirt.
Load a primative plane. Use pic 3 as the diffuse map for the plane. Then, start making different opacity maps to carve up the grid in different ways. .. play tic tac toe or something... so you understand how it works. Load pic 3 AS the opacity map on a plane WITHOUT a difuse map and just a color....see what happens. Once you understand how they work, it'll make the shirt cut easier.
delete
Ok I was with you until this bit. Remeber I am using GIMP I have done everything so far and have the image in there (pictured) do you use GIMP? could you guide me more through adding the layers in GIMP because I am confused there.
Sorry. I don't use Gimp.
I played with GimpShop..a Gimp version designed to be more like Photoshop ages ago, but I don't remember anything on it...
http://lmgtfy.com/?q=gimp+add+layers
Ok you mind if I get back to you once I sort this stuff out? I appreciate your help so far.
In GIMP, in the box in the upper right, the one that says Layers....right click in it and a box will pop up, one of the items is New Layer...and when you click that it will give several options...you can give each layer a name, what the base color is/transparent, etc
On the image of GIMP you posted, the Layers and brushes tab is on the right hand side. The box with the bump map image in it is your layers pane. Right click in that and select 'New Layer' to create each new layer. when you do, a dialog will pop up that allows you to select what colour the layer will be filled with when it is created. This includes an option for white and transparency - use the latter for the empty one.
If you need to reorder the layers just drag them up and down.
If you want to master this I suggest you Google 'GIMP layer Tutorials'. there are loads of tutorials that will help, and they dont take long.
Sure...like I said, though, experiment with the plane primative to understand the concepts...
figure out how I made the following..that's all you need to know to get going :)
If you're doing more than one picture making an opacity map of the item would be easier. If you aren't, a viable method would be to render twice - one with the shirt and one without, then use postwork to add the skin section to the one with the shirt, since you are going to do postwork anyway.
Can I ask what program you are using to do all the work you have done with this?
Ok do I have right right Layers up on the right in GIMP. I picked a transparent layer and white one. Is this correct? (sorry I am so slow with all this)
To answer diogenese I think I will try with the original method for now but thanks.
I use Photoshop.
For your gimp pic, yes, that looks good. Now, if you click the "eye" next to the white layer, it will hide it. Then draw on the transparent layer with black.
Then unhide the white layer and save or export it as a png or jpg.
Attached are the opacity maps I made for the picture above. Do you understand how they made the pictures above work?