Saturday, August 29, 2009

How To Draw Anime CG: Colouring 2

Now it's time for the biggest step: shading.

To start with, make a new layer to store your finished shading. You might want to make one per colour or one per area; however since you have the masks that you made in the previous step, I find it more convenient to just put all colours of shading onto one layer and use the mask to seperate them if I want to adjust colours.

When shading an area, the first step is to choose your shading colour. Grab the base colour and adjust it as you see fit; typically you'll be reducing both the saturation and brilliance, but it's often nice to change the hue a little as well. The hue changes due to the effects of ambient light; it's particularly affected by unusual lighting conditions too, such as moonlight or otherwise coloured light (go look at other art or photos).

Another case where hue is affected is skin colour; skin is slightly transparent, and so the red colour from capilliaries tints the shadows slightly red - ever tried shining a torch behind your hand? Here's a basic description; it gets kind of technical when applied to human skin, so try observing photos and so on, or just wing it.

Time to get started. Make a new layer, and throw a blob of colour on that is bigger than the shading you want. Use the mask to trim the unwanted bits, and manually trim anything that overlaps inside the mask where you don't want it to (its easier of the initial blob doesn't overlap, obviously).

Now, grab your eraser, set it to be a soft brush of appropriate size, and trim away parts of the blob to give a nice gradient edge. Use different sized brushes to give different gradients - here I used a 65px, 35px and 17px brush, with strokes as illustrated in the 2nd picture. This gives you a good amount of control over the shading - I find that its much easier to form smooth gradients by removing colour with the eraser brush rather than trying to add it with the colour brush.

I don't want to force my opinion of how to actually perform the shading, since I don't think I'm particularly good at it; still, basic advice would be to keep in mind the position of your light source, since you are effectively drawing shadows, and that when it comes to anime-style CGs, its generally both nicer-looking and faster to keep things simple.

Another odd rule is that it looks nice if you erase a little of the shading where it meets the lineart (as with the lowest 17px stroke above). I'm not sure why; something to do with ambient light and reflection? But you can see it a lot on professional drawings; it looks nice, especially with skin.

Once you are done with the blob, you can merge this layer back with the rest. If you are happy with it you can merge it back into the main shading layer; I tend to keep a main layer for the whole masked area that I'm currently working on so that I can touch it up before I merge it back to the main layer. Be careful that you don't accidentally merge layers badly and ruin your base colours or masks! Plus, be careful to apply the mask to the area before merging back into the main shading layer or you might end up ruining completed work - I haven't found any quick, practical way of preventing this, so you'll just have to be dilligent and keep a large undo stack...

Keep making layers, trimming blobs and merging back until you've completed each masked area. Since the brushes have a limited size, you can save some time by doing several blobs at a time, spaced apart enough that you can erase one without overlapping with the next one. For example, I painted half the fringes on one layer y doing every other spike, then the other half on a second layer, instead of making one layer for each spike.

And so, we have a shaded Miku. We're not done with the shading yet though...

Wednesday, August 26, 2009

How To Draw Anime CG: Colouring 1

The lineart is done; now it's time to start colouring!

The first thing I do is set a grey background. This is partially so I can see colour bleed more easily, but the main reason is to set the overall tone of the picture - white is very distracting when I'm trying to choose colours.
Since I want pale colours, I go for a fairly pale grey.

A quick note on choosing colours. If you're not used to colouring stuff then it might be a good idea to sample pictures that are similar to what you want, at least to see what colours are typically chosen - its somewhat hard to guess the RGB values of a colour just by looking at it, at least at first. Make sure you sample the base colour though, without any shading added to it.
If you sample colours from various galge CGs, you'll probably notice that whatever the hue you're choosing, the colour is always very saturated - towards the top and right sides of the colour picker. CGs always seem to use vibrant saturated colours - even when a grey is seen, it typically has a large amount of saturated colour in it (often blue or red). It's pretty rare to see a true grey (ie. no hue / saturation) used. This isn't a rule or a recommendation, just an observation.
The usual colour associations apply (blue for cool, red for passionate, etc) but you'll probably notice a lot of complementary or opposing colours being used.

Time for some colouring. The REALLY important thing here, rather than just colouring the areas, is to establish a mask for each area of colour. You could do that with layers and masks, or by using a layer per colour; the method I tend to use is to paint all the colours on one area using the pencil tool (which has no blending). This gives me a bunch of areas of solid colour that I can select. This mask allows you to adjust your colour scheme easily, and is also used extensively for shading.
Obviously, you can use the flood fill tool and your lineart to speed things up a little. You can also use the masks you have already completed to easily create the mask for neighbouring areas, since implicitly there won't be any overlaps.

Keep going until you fill in all the whitespace in your lineart. Once it's all masked, you can fiddle with the colours until you're happy that they work together.
Note that even though she is wearing grey, it's actually tinted blue - compare it to the background grey. I used blue to complement her green motif and skin colour. Or something.

Thats all we need for base colours and masks; next is the start of shading!

Sunday, August 23, 2009

How To Draw Anime CG: Lineart

I always wanted to do some kind of tutorial covering the stuff I've picked up from scattered other tutorials. And since I'm too lazy and uninspired to draw anything else I guess its a good time to put one of those together!

I'm not intending this to be a 'do this for good art' kind of thing, since I'm far from being an authority on either art or techniques; this is just going to be a summary of the basic stuff I go through to make a picture, in the hope that people who already draw and are exploring ways to make clean art find it useful.

Some general comments before I start:
I use PaintTool SAI for lineart - it has some really nice control settings for lineart, so you can do nice crisp thin lines - Photoshop has some settings for that but it isn't convenient for doing both lineart and colouring. SAI is god for painting, but I don't tend to do that, and I still prefer Photoshop for CG colouring.
I have a 1200 square canvas (so it's roughly screen-sized at 100% zoom), and draw the roughs at 100% and the final lineart at 150% - this is to speed things up without it looking crappy, and also so the lines are a good size on screen (a couple of inches on a tablet - this is more important for me than resolution). I have a layer with a block of colour on it that I use to crop a nice view of Miku before saving. I'm also using a hard 12 pixel brush, but due to pressure variance I'm probably usually drawing a 5-6 pixel line - for the resolution, even this is probably quite thick, but I tend to resize the image a little to hide minor faults. Its also easier to colour lineart that is at least 2-3 pixels thick. Uh, I can't think of anything else...

So! Lineart! As an arbitrary subject, I'm doing Hatsune Miku, since I wanted to draw her sometime, and I wanted a subject who lent themselves to fancy game CG-style shading. I was going to have her singing, but I dropped that and kept the pose simple since it's a tutorial...

I start off with a layout sketch for just about anything I do; it helps break habits, and also avoids problems later on with propertions. Only the silhouette is important, really; the eyes and some details are there but only to make sure they're positioned correctly but I'll be redrawing them when I'm 'inking' it.
If you're good at drawing on paper then you can scan the rough and skip to the inking. (If you're good at inking on paper then you should probably skip all of this...).

Since the hair is kind of complex and overlaps, I do the rough for it on a seperate layer. The previous rough gets set to 10% transparency so that I can still see the silhouette, but it doesn't interfere with the current work.

The clothes are next. They're also done on a new layer. Since they're based on the previous layout and I seem to be pulling it off ok, I skip the rough and just ink directly.
'Inking' is just a process of producing clean lines - I don't want to try to influence anyone too greatly since its an artistic choice, but at a technical level, this basically means doing each line as one stroke, or hiding the fact that it isn't if you have to break it unto two unnaturally. For me this means lots of undo-ing when I don't like a line, or using a temporary layer to clean up the line if I can't avoid overlapping other lineart (such as when two lines meet and I want a nice join). Beyond that, look at what your favourite artist does, or look at how people do particular areas - as example, a lot of people thicken lines on the chin or eyes in particular ways, or vary the thickness a lot on lines that are curved.
Here's a video of Gabe from Penny Arcade inking a picture, which demonstrates the 'single stroke' thing pretty well:

(Don't worry, it's running at 2x speed, he's only semi-superhuman.)

Skin parts and face. I did this on a new layer, then cleaned the overlapping parts and merged back into one layer since there are no overlapping parts. After this, I'm done with the body rough so I hide it.

Hair next. Since it overlaps the face it gets a new layer. I redrew a bunch of stuff from the rough - it's just a layout so I don't bother with details, but I also decided that the hair ornaments were a bit flimsy in the rough and beefed them up. This is a simple picture, but normally I do that a lot more.
Again, I turned the other lineart transparent while I was doing this so that it didn't distract me, then made it opaque again once I was done. The hair rough gets hidden now too.

Time for some greebles and fixes. After seeing it with the hairline, I didn't like the haughty expression, and since the face is a seperate layer I just fixed it without redoing her hair. I also noticed that I'd missed some details from the original design, and fixed her skinny arm - you can't meddle too easily once you start colouring, so it's now or never.
After this, hide all your roughs, and lock your lineart layer so you don't draw on it like a dumbass... You should also set the layer to 'multiply' if you have it on a white background, the white becomes transparent and the black remains.

Another thing you see a lot of is that, when people are posting lineart they intend to colour later, they touch it up a little. Just duplicate the lineart, do a light gaussian blur on one (2-5 say, depends on how thick your lines are), group them with a colour layer, and you're done.