Monday, 2 January 2017

Adding 'universal background animals': kwals

The Book is over half done and is changing as it develops. I started by repainting existing oil paintings digitally, and by now most paintings with a pleasing design have been done. At first the paintings were merely cleaned up and details were added, but in the latest cases not a single pixel from the original painting survived: they were completely recreated from start. More importantly, the content changed: writing more elaborate texts forced many story elements and biological principles to be firmly defined for the first time. The painting 'arrival at Furaha' is a good example of this process (first post here, last one here): painting an internal  spaceship scene forced me to turn my previously rather vague ideas how they might work and in-world design aesthetics into written concepts and painted shapes that will guide things coming later.

The next big step will be finally defining hexapod legs: I will have to decide once and for all whether each of the three pairs of legs will start with zigzag pattern or with a zagzig pattern as well. It is the middle pair that causes headaches: its design should not simply mimic that of either the first or the third pair, so how do I make it work? My thoughts on that subject are slowly coalescing.

But meanwhile another thought came up. So far, the animals in the paintings are fairly big and conspicuous; but how about the 'small fry', all those little creatures that together make up much more of the animal biomass than big animals do? Shouldn't I give them some attention? But what of their shapes? Must they all have truly alien shapes, or should they simply look like they were taken from a textbook of Earth invertebrates? Currently, I think the latter probably applies, based on two considerations. The first is the enormous variety of invertebrate shapes on Earth; it is hard to come up with an original design when evolution produced many oddities that would be dismissed as impossible if they were presented as fictional animals. The second consideration is that some principles will apply universally; streamlining must be a universal solution for moving through a fluid at any speed.

The challenge, of course, is to push their design boundaries a bit. They may not always be possible: 'worms' are probably universal. I mean small boneless elongated burrowing animals with a round or flattened cross section. So The Book shall contain at least one spread on 'wurms', and I doubt that I can come up with designs that do not already exist on Earth. A second group to merit attention are arthropod analogues: insects, spiders and the like. I already designed some of those: spidrids and tetropters. But the concept of a small bilateral exoskeletal segmented animal seems so good that it is hard to avoid. I will name the Furahan reprentatives of this design the name 'wadudu'; this is one of the remnant Swahili words left by the spacefarers of the good ship 'Ngonjera'.
Click to enlarge; from http://fox.rwu.edu/jellies/
Earth's oceans are full of jellyfish for the last 500 million years. They are radial bell-shaped organisms without complex nervous systems that move in a simple cycle: the bell contracts, water is pumped  downwards and by reaction the animal moves upwards. Then the bell relaxes , becomes broader and lets in water again. This has always seemed a bit odd to me: when the bell relaxes, it flattens but also broadens, which must hinder its upward movement. Also, water has to flow upwards into the bell from below, which must because an equal but opposite reaction pulling the animal down a bit. That was my unconsidered opinion, but recent studies showed that jellyfish swimming is much more sophisticated that I thought. Some swim as I described, by jetting water downwards. Those tend to be bullet-0shaped. The flatter ones drive down a toroidal vortex of rotating water, and that actually pushes water back up underneath the bell, pushing the jellyfish up when the bell is relaxed. Here is a very nice website explaining these matters.

video

And the video above shows the toroidal vortices that provide propulsion even in the relaxed phase. The paper to which the video belongs was published in PNAS and is freely available.
 
I wondered whether there was room for creativity here. What if some water can flow downwards right through the jellyfish while it is moving passively in the relaxation phase? Making a hole in the bell will of course impair its propulsive upwards force when the bell contracts, so the hole should be open during the relaxed phase to prevent the animal being sucked down, but closed when it contracts? Valves should do the trick, shaped perhaps like those in the mammalian heart. The ones in the aorta are a useful example: they open when the ventricle pushes blood out, and close to prevent blood flowing back into the relaxed ventricle from the aorta. I decided to play with that idea a bit, and give Furahan jellyfish analogues a twist.

Click to enlarge; copyright Gert van Dijk
Here is such an animal in a rough sketch. The first image shows that there are three valves. Instead of one central bunch of tentacles, as in Earth jellyfish, there are three outlined here. I may make the body less perfectly circular to reflect this triune design. 


Click to enlarge; copyright Gert van Dijk

This cutaway shows a section just off centre of the animal, a bit near the camera. The cut goes through the two nearest valves and as you can see they are closed. This is what their position would be during the propulsion phase, when the bell contracts so pressure is high underneath the bell.   

Click to enlarge; copyright Gert van Dijk
And here is an open phase, with the valves apart from one another. I should have drawn the rest of the bell in a more relaxed shape, but thought this would be enough to convey the idea. 

So there we are: Furahan jellyfish analogues. I do not wish to simply call them 'jellyfish', so they needed a name that would in the Furahan story setting. In Furahan lore, settlers came mostly from a Western European background with a smattering of people from other parts of the world (the down-to-Earth reason for that is that I am only comfortable with a few Germanic and Romance languages). I looked up the word for jellyfish in various languages (here is a site to check some all at once for yourselves).  Many languages use variants of Medusa (the Greek monster woman whose hair takes the shape of snakes and whose regard turns you to stone). I like the Brazilian name 'agua-viva', or living water; very poetic. But I will go with the German and Dutch variants of 'Qualle' and 'kwal', words that evoke a soft flabby and unpleasant nature. I considered an anglicised version in the form of 'quall'. To be certain I checked, and found that 'quall' already has a meaning as yet completely unknown to me. Hm. I had better avoid that connotation. So, 'kwal' it will be, unless someone comes up with a better suggestion. Actually, the 'a' in the Gemran and Dutch versions sounds like the 'a' in 'father' or in British 'bath', but for Furahan purposes a pronunciation like an 'o' is the likelier one.  

Sunday, 23 October 2016

Arrival at Furaha V: done!

Here is the result of all the previous processes. Is the painting ready? Mostly, yes. There is always a possibility that I decide to change something one day. Sometimes, when finishing a painting, I feel certain that the way it is then is the way it will stay. In other cases I am much less certain, and the 'arrival' painting is one such. It will probably undergo some changes in the future.

Click to enlarge; copyright Gert van Dijk
But here it is, for better or worse. The original is 6000 by 4200 pixels, so what you see here is much reduced version. A problem of this design is that it was difficult to work out how much detail and colour there should be in the foreground. One extreme would be to paint the foreground as pure silhouettes, and the other would be to add strong lights in the spaceship so every detail in the foreground stands out. I decided on something in between, and the balance turned out to be tricky: with too much light on the walls these start to be disruptive, in particular in view of the array of colours I gave them, in an attempt to give them a brushed metal look. But it is easy to darken or lighten specific layers in a digital painting, so I can tweak the settings later. I will not look at it for a few months and then it should be obvious whether the balance needs to be changed.

Click to enlarge; copyright Gert van Dijk
Here are the protagonists, Giorgios Bruijningh and Souren Nyoroge. It is interesting that in close-up the colours are much more obvious than in the overall view, in which they are more or less swamped by the planet. The lettering on the window is an attempt to add a bit of futurism. The text is in Neolat, an adaptation of Latin that is very easy to learn for speakers of Romance and Germanic languages. That, at least, is the 'in universe' statement: on our world Neolat does not exist. It could do with another font, but I have not found something suitable yet.

Click to enlarge; copyright Gert van Dijk
And here is the ship's cat. This fragment also brings out the Art Nouveau decoration on the floor. I took this from the internet, reworked them a bit, deformed them to get the corrected perspective, and positioned them on the floor as a transparent layer.

So far, I had not painted the technology of this universe. I do not really want to, as it would detract from what it is all about, and also because I do not think I would be good at it. But Spugpow's remark regarding art Nouveau was right on the mark. I may write about that subject another time, but my preference for the aesthetic sensitivities of this future civilisation would be much closer to Art Nouveau and steampunk than to cool, sleek and empty designs. The 'bandes dessinées'  by Schuiten and Peeters come close. Their series on the 'cités obscures' are close to what I would like to see. Have a look at a Google image search of their work here, read the Wikipedia article, or go their own website. The books do not seem to be readily available in English for reasons I cannot fathom.

Click to enlarge; copyright Gert van Dijk
Finally, it struck me that the painting would serve well as a book cover, so here is the novel 'An unexpected friendship', by one Sigmund Nastrazzurro, a hack writer of little fame.

Thursday, 20 October 2016

Arrival at Furaha IV: progress


video
Well, here is the next video. It shows some further development of the characters. These were painted against a white background, and what you see in the video is that their silhouettes were then painted in a flat dark brown tone. The layer of the silhouettes is underneath the one with the shading of the characters. By setting that shading layer to 'multiply' the colours in that layer will interact with the layer underneath in a specific way. Generally, 'multiply' adds portions of the images that are dark in the shading layer as additional darkness to the silhouette layer, but any light portions will not lighten the silhouette layer.
  Afterwards, I flip on the 'walls' layer as well as the planet layer, that here is simply a render from my Furaha model in Vue. To get a more painterly effect I will later paint it completely anew; actually, at the time of writing I have already done so.
  In the meantime I also reworked the walls. I liked Spugpows remark that the walls had an art nouveau feeling, so I took that literally and decorated them and the floor with Art Nouveau patterns. I will probably show the result of that in more detail next weekend.       

Saturday, 8 October 2016

Painting Arrival at Furaha III: characters


video

In this video I am trying to get a feel for the characters. I added a cat for some mystery; if you have a very large roomy spaceship, you can have a ship's cat too, I thought. Besides, by having it look at the viewer the painting becomes more interesting.
  In the next stage the feeling will change completely: here, the canvas is very light, but the painting as a whole will be dark. It is just easier to sketch clothing this way. I decided that the temperature aboard ship is fairly high, so people wear loose clothing. 

Monday, 3 October 2016

Painting 'Arrival at Furaha' II: how thick is the terminator?

No, this is not about the waistline of an ageing time-travelling cyborg.

A 'terminator' is also the boundary line dividing the dark and sunlit areas of a planetary surface. The Apollo missions made it very obvious that the terminator, in the case of Earth, is not a thin sharp line but rather a blurred zone in which light fades from full sunlight to total darkness. In the case of the moon it is much sharper, suggesting that our atmosphere has a lot to do with blurring the terminator. Once I had asked myself how wide it should be, I felt it difficult to simply guess its width. I thought it would be easy to find on the internet, but to my surprise it was not. So I did some simple mathematics.
Click to enlarge; copyright Gert van Dijk


In the scheme above the circle at the left is a planet, and the one on the right is the sun. On a point on the day side of the planet a viewer can see the entire disc of the sun. But when the sun sets, part of the sun's disc drops beneath the horizon; in other words, some of the rays of light from the sun cannot reach the surface. So which is the area on the planet where only part of the sun's disc is visible? That area is the terminator.

Point A above is where a tangent line from the 'top' side of the sun just touches Earth, and point B is a similar point where a tangent line from the underside of the sun touches Earth. The zone from A to B is the terminator, and it is not difficult to express that in angles. But that is all without an atmosphere. I reasoned that the same tangent could travel on through the atmosphere, where it could scatter in the atmosphere, casting some light on the surface. So I also calculated point X as the furthest point where light might be scattered.

The trick then was to put in the proper values, in units of one thousand km. The radius of Earth becomes 6.371, that of the sun 693.7, the distance between the sun and Earth is 149600, and the thickness of the atmosphere is 0.1. Mind you, that latter value, 100 km, is the 'official' border of the atmosphere, but a more relevant value would be the height where light is scattered; I have no idea.

Click to enlarge; copyright Gert van Dijk
So here is a close up of Earth with the proper values put in. The thing to remember is how large space is: the distance between sun and Earth makes all the triangles extremely narrow. The angles of point A and B are 179.7 and 180.2 degrees (the angle starts counting at the top of the planet, so 180 degrees is pointing straight down). That is only 0.53 degrees! I thought the effects of the width of the sun's disc would be larger, but mathematics doesn't lie. The angle for point X is 190.3 degrees, so the angle from A to X is 10.6 degrees. That is closer to what space photographs suggest. But how correct is it?

Click to enlarge; copyright NASA

Above is an image from NASA, rotated. I put some orange dots on it, over Gabon, that to my mind define the width of the terminator. I compared that to a map of Africa, and estimate the width to be five degrees. So apparently I overestimated the height where light gets scattered. The lesson is clear: the width of the terminator depends almost entirely on the thickness of the atmosphere. Good; I can now plug in the values for Furaha and paint the terminator at the correct width. Well, a useful estimate, anyway.       

Next time I will show some timelapse video's of the painting as it progresses (as soon as I manage to upload them, that is).

Saturday, 24 September 2016

Painting 'Arrival at Furaha' I

I will try something new: I will document how I produce a painting, meant for The Book, as it develops. I always said I would not show new paintings, as that would probably ruin the chances of ever getting the book published. I decided to make an exception: the painting I have in mind is not a major one showing an animal or plant, but a minor one showing the human side of affairs. As you will see, digital painting uses a variety of digital techniques to help find a good composition, get the perspective correct, etc. I am not alone in this: If you read books on digital painting techniques, you will find that professional illustrators do this all the time. 

I needed a minor painting for the two-page spread introducing the chapter on the Nu Phoenicis solar system and the planetology of Furaha. These chapter introductions show a minor painting and a quote, usually from Souren Nyoroge, whose book 'Furaha and Earth: similar in their differences' elevated him from one from one of The First, to Furaha's foremost historical hero (I may slip from real life comments on the painting to 'in universe' remarks, so pay attention).

The quote was about Nyoroge, the scientist, and Bruyningh, the agitator, looking at the planet after arriving there and realising that from that point on it was not just a planet, but their World. That point in time seemed a good theme for a painting and I already had a scene in mind, with the two of them looking at the planet from their spaceship, silhouetted against the blue sphere of the planet. Over 20 years ago I photographed friends of mine in the Vancouver aquarium, silhouetted against the blue waiter of a large tank with beluga whales, with vertical window frames separating the worlds on either side of the glass. I would like to show that photograph here, but have no idea where it is. No matter: a Google search for 'Vancouver aquarium silhouette' will show you that many people took very similar photographs. However, there are no vertical window frames in the Vancouver aquarium, so I must have added the notion that there were any there to my memories at some time. Memory is  malleable.anyway, the mental image, with frames, looked better than the true view without frames, so I  went with frames. The design is simple: two silhouetted people, window frames, and a planet.

Click to enlarge; copyright Gert van Dijk
I have always illustrated the sizes of Furahan animals by adding the silhouette of a human, and these humans do not just stand there, but usually do something (I have seen others take up the habit of having 'scale-humans' do something, which I like). I either draw these silhouettes by hand or base them on a photograph of someone posing, which is them modified as much as it needs to be. Above are two such recent silhouettes. One was hand-drawn from the start and the other is based on a photograph; guess which is which...

For the 'arrival' painting I could have chosen the same route, but quite by chance I came across the free program 'MakeHuman' that looked like it could be useful. It starts with a generic 3D human of which the age, gender, height, weight etc. can be adapted easily. I made a slender character (Bruyningh) and a stockier one (Nyoroge). So far so good. But then I found that you cannot change postures in the program itself, but have to use Blender instead. Unfortunately, I cannot work with Blender; I find its interface incomprehensible (it is free so is certainly worth having a look). That's the end of MakeHuman for me, then. Luckily there were some example postures included, so I used those to export the two characters. These were not what I wanted, but I could easily redraw their anatomy and pose later; the 3D objects only serve as scaffolding for the drawing anyway.

Click to enlarge
The next job was to import these persons into Vue Infinite and to construct a spaceship. Luckily, all I needed of that spaceship was a floor and window frames. I wanted very large windows to give a luxurious feeling and allow the planet to be shown as a large object. I used 'cubes' to built the frames, imported the characters, hung up a big blue sphere and added some lighting. After that, I moved the 'camera' around to play with the composition. Above you see a view of the Vue programme showing the characters on their tiny section of spaceship.

Click to enlarge; copyright Gert van Dijk
And here are a few images of the results of this early stage. I decided to go along with something like the third one. At this point, I haven't started to paint yet, and I will keep that for the next instalment. But there are quite a few things to think about:

  • I have to change the blue sphere into a proper Furaha model (I already have one). I will have to work out where the 'terminator', the line dividing night and day on a planet, should run. It has to look attractive but also has to be correct. This also includes working out how wide the blurred part of the terminator should look. The mathematics of calculating that should be easy, but I will check astronomical sources anyway.
  • The window frames look fairly boring; perhaps I should change their shape
  • The humans should get clothing; what does one wear during protracted space travel? Is it hot on a spaceship?
There are other implications: the image tells a lot about the Furaha universe. If people stand on a floor in a spaceship, they either have shoes that stick to the floor, or they have artificial gravity. I'll go with the last choice. So do almost all science fiction movies, so I doubt many people will even notice. 
  I already had a concept in mind of how people get around on Furaha: they use large lumbering vehicles that float in the air much in the same way that bricks don't (yes, Douglas Adams said that). They use a gravity-repulsing mechanism as a reverse zeppelin. A true zeppelin uses a great volume with very little mass to lift a few kg of mass; well, the repulsor zeppelin also lifts just a few kg, but using a great mass. Don't ask for blueprints. Not yet, anyway. This 'Leyden Mass Repulsor Net' (TM) works for spaceships too. Quite well, in fact, as its efficacy increases more than linearly with its own mass (I just made that up). Basically, you wrap the Repulsor Net (TM) around some mass, such as rocks, lots of water or a concrete-filled submarine, apply energy to the net and there you are.
  So all this explains why there is artificial gravity on the spaceship, why spaceship designers do not care about saving weight (the opposite, in fact), and in turn it explains why they can have large windows.

Tuesday, 26 July 2016

What do Roman soldiers, trilobites and the Furahan Droodle have in common?


Click to enlarge; copyright Gert van Dijk
Before answering that, you are probably wondering what a Furahan 'droodle' is. Well, one description found in the 'Annals of IFB Field Expeditions' reads as follows: 'The droodle is a slow an silly creature, behaving in its snug little world like the Lord of Creation, notwithstanding its utter insignificance'. Apparently the Annals did not require any semblance of scientific impartiality before accepting contributions, but that is not the point. Further on the author continues: "It can behave this way because it is well protected because of its foul taste and because of the overlapping armoured plates covering nearly its entire body."

An early version of the droodle is shown above. And there we are: the droodle has an armour consisting of overlapping plates, and so did trilobites, and so did Roman soldiers. I came across the subject when I was preparing to paint the droodle anew for The Book. Most of my new paintings have very little to do with the old ones, but I like some old designs enough to go over them again, taking the opportunity to improve them in as many ways as I can. I started wondering how animals manage to move while covered with what seem like very stiff plates. How are these plates attached to one another? Obviously, in arthropod legs the exoskeleton of adjacent parts of the leg form joints that often have just one axis of movement, much like our own knees: we can bend it stretch a knee but it does not move sideways nor can we rotate the leg and foot backwards. I started thinking about whether that also applies to the plates covering the droodle.

Click to enlarge; copyright Gert van Dijk



Above you see the result of simple experiment: I wanted to form successive hoops curving around the animal's back while widening at the sides. I imagined a hinge between two hoops with the axis of rotation about halfway up the animal. Of course, such an axis of rotation would make sideways movement impossible, but so be it. I assumed that the plate in front would slide over the plate in back. I could imagine that in my mind's eye for half-circular hoops, but felt I needed some visual help with hoops that widened at the side: could they in fact slide over one another over their entire length, or would they intersect, making the movement impossible? So I made a rough shape like that in Vue, of which the top surface represents the plate. As you can see, at the centre one hoop can easily slide under the next one while it wants to move over it at the sides. This does depend on the site of the hinge and some other aspects, but it does show that you cannot assume any angle or shape to work. I could of course still paint it the intended way and no-one would be the wiser. But science has preference over art in such matters. So what was wrong?
 
Click to enlarge; Manton, The Arthropods 1977
I then thought of trilobites: their name indicates that their bodies had three lobes lengthwise, with a thick part in the middle and much narrower side flanges, much like the droodle. And trilobites could roll up their bodies, so they solved the problem how to slide one hoop under the other better than I had (weel, they had more time...). I obviously needed expert guidance, perhaps a book called 'Biomechanics of trilobite intertergite movement' (the hoops are called 'tergites', just so you know). I found something close: 'The Arthropoda' by S.M. Manton, 1977. I am not new to reading scientific papers, but this book is as intricate as it is condensed: the reader is assumed to be rather well-versed in arthropod classification and anatomy. The book contains sentences like 'There were no coxal endites or gnathobases.', in its own way as wonderful as 'It was a dark and stormy night'.

Click to enlarge; Manton, The Arthropods 1977
So here is Figures 1.5 from that book: have a good look at the top right in particular: the tergites are connected by a fold of skin, doubling back on itself. There is no hinge to be seen anywhere. If the tergites are indeed connected only by such a fold over their entire length, they would have much greater freedom of movement than if there were just one axis of rotation: this is a good idea.

I then wondered if his is how all armour segments are connected in arthopods, and browsed through the book. As you would expect, there are a myriad adaptations of tergite movement. In species that burrow, successive tergites are kept from sliding over one another and have a built in 'door stop', allowing the animal to push the soil out of its way. In other species there are additional small tergites normally hidden between larger ones. When the body is flexed, the gap that would otherwise appear between the large ones is filled by the small ones. In many cases tergites only cover the back of the beast. There may be other bits of hoops at the belly (sternites) or the sides (pleurites), all of which are connected to one another by the folds of skin.

Click to enlarge; from The Arthopods, SM Manton 1977
Here is an example of the intricacy of the internal anatomy of a millipede. The large top image shows the poor millipede cut lengthwise with its body flexed (the back is at the top). The lower left image is a horizontal section of the body rotated sideways. Complex, aren't they? The feature I would like to call your attention to is the folding of the skin between tergites: I found that in all such plates.

So I learned from all this that arthropod tergites can in fact be connected by 'hard points', but in many cases the skin folds allow flexibility and freedom of movement. So that was one problem solved, but all this did not answer the question how to ensure that the tergites do not 'intersect' while rotating, as they did in my simple model? Or how do you avoid having large gaps form when the animal moves? There may be several answers to these questions. Perhaps the tergites should be flexible.


video

( video does not seem to work; I will check later...)
Have a look at the YouTube video above, of a millipede flexing its body in all directions: the tergites do not show any gaps at all, and yet they slide over one another in at least two directions of rotation: they must be flexible. But would that work for a big animal, in which you would expect the tergites to be stiff? (but never brittle: the armour must be capable of withstanding blows, and allowing it to deform it a bit should absorb the energy of a blow). 

Another solution would be to forgo tergites that run from one side of the animal to the other; split them up in separate parts instead. These smaller plates could each be tough, and be connected with skin folds. At the top of this post you'll find a simple model I made to see what a droodle designed in this manner might look like. Mind you, this is not what the painting look like: the droodle has already evolved some more and no longer looks like this, but it does still have multiple overlapping tergites.

Click to enlarge; source here
So what about the Romans? Everyone who has ever seen a film with Roman soldiers in it, or who has read an Asterix book, knows that their armour consisted of metal hoops circling the soldier's body. This seemed very similar to the tergites of trilobites or other artropods, so I wondered how the legionnaire's hoops were connected, That was easy to find out: there are books describing actual archeological finds. The image above is from tha reconstruction based on such finds. The Latin word for this particular type of armour is 'lorica segmentata' ( I also leaned that all these films might be wrong: this plate armour type may not have been the standard type of armour; chain mail may well have been more common.) And here is how the loops are connected: not by hinges, but by leather straps on the inside of the hoops.

video
( video does not seem to work; I will check later...) 
The video above shows the Roman lorica in action (the inside is well visible two minutes into the video). The hoops could slide and rotate a bit with this arrangement, in exactly the same way that the tergites of trilobite could slide over one another thanks to being connected by folds of skin. Only the trilobites had their armour some 520 millions of years before the Romans invented their lorica.

So this is how the droodle came by its armour and by its scientific name of 'Lorica segmentata'. There is a long list of items the Romans did for us, to which I would humbly like to add that they can make you think how exoskeletons work. Not a bad thing at all.