Well, I have spoken about this a lot around the forums, but because not everybody reads everything and for future reference, I have made a tutorial for the hull shading method I use, called the 45 degrees rule.
There is something that must be kept in mind first. Hull shading is something that was not in the original sb shading rules, and is something that is not and will never be mandatory. It is also not something that is meant to let ship drawings look good. There are only 2 reasons why you should use hull shading:
- Because the complex hull shape cannot be represented accurately otherwise (for example,
https://dl.dropboxusercontent.com/u/632 ... nguard.png)
- Because you have great references for a hull shape and thus can represent the hull accurately on your shipbucket drawing. (for example,
https://dl.dropboxusercontent.com/u/632 ... 47%202.png)
If you do not know what the underwater hull is shaped like, because you have no lineplan or no perfect pictures of the ship in drydock, don’t do this style of shading. We on shipbucket all have some kind of knowledge on ships, and if we see a ship that is not that far out of the ordinary, we can see how the hull is shaped. However, if you are just estimating something, you are kind of stating ‘this is what the ship looks like, and thus providing an inaccurate sb drawing.
It is not wrong to use an ‘estimate’ method for never build designs, and for own designs you can do whatever you want as long as it looks somewhat realistic, but for both you should look at real designs to get the ships shape within realistic margins.
The basics:
The 45 degrees shading rule is quite simple. Everything that is more horizontal then vertical gets shaded. So, where the hull is vertical (90 degrees angle with the waterline), it is unshaded, where it is horizontal (0 degrees with the waterline) it is shaded. The edge of the shaded area is exactly in between: 45 degrees with the waterline. Sounds confusing? Let me show it with a simple example:
The blue Line shows the waterline, the red line the 45 degrees angle. The black line is a hull shape that you can find on long keeled sail boats and sometimes in the stern of ships.
Between the green line and the yellow line it should be shaded, because this area is facing more than 45 degrees downward.
That is not that hard, is it? The problem is that you have to do this for as many cross sections as possible. Of course it is not expected of you that you check every single pixel, but try to do at least 5: shape of the stern, midship, bow, and a point in between. In shipbuilding, it is common to work with 20 ordinates, so more than 20 is never required of you. The ship’s hull is fluent in shape, so the edges of the shaded area should be fluent too over the ships length. If there are knuckles in the line, then there are bends in your ship.
I have made another example for what this ends up like. It is a very basic shape, similar to that of small multipurpose freighters here in Europe, but a bit simplified for this tutorial. It is thus not a representation of any real ship, and should not be treated as such.
The first image is an unshaded hull. The second has some cross sections drawn in. the cross section positions are red, cross sections green and the 45 degrees turning point is blue.
In the next 4 images it is shown how you get from these markings on the cross sections to the shaded drawing: first you move the 45 degrees points to the correct cross section, then you draw lines between the different points, then you make the line fluent and shade the area underneath/between them.
In addition to what is shown here, I also use 3 additional parts of the shading:
- Shade lighter the parts facing up (for example ducted propellers or torpedo belts). Here count the same rules, just facing the other way.
- Overhang shade under overhangs, even under water. (This is just the standard sb overhang shading, and I only use this when it is not clear otherwise there is an overhang. This is mostly the case in the stern when a skeg is used. It is NOT usable for shading under bilge keels)
- Above the waterline shading. It is best to stay consistent in the shading style from keel to main deck, as these parts run over into each other fluently.
Use this thread to ask questions, if things are not clear. If it is necessary, I will expand this post with more examples (different ship types) and I will try to incorporate the answers to questions asked below into the tutorial above when there are things that I forgot.
I hope you all have some use for this, and that with this I never have to fight anyone because their shading does not represent a correct ship