★ APPLICATIONS ★ CREATION GRAPHIQUE ★ The Landscape Creator|Amstrad Computer User) ★ |
| The Landscape Creator | Applications Creation Graphique |
This type of exercise helps to demonstrate the sheer power and versatility of the Amstrad. These pictures were produced by the Landscape Creator, a machine-code program which uses mathematical methods to create detailed coloured landscape views, quickly and spontaneously. The program was designed specially to take full advantage of the excellent graphics on the AMSTRAD machines. I set out to simulate the idea of artistic creativity; the program makes its own decisions about all the variables relating to the sky, mountains, vegetation, lakes, islands, buildings, and then draws the picture. The sheer number of variables chosen by the program means that the resulting scene gives endless, unexpected, surprises with a wide range of possible colour schemes. Generally speaking, very little “Computer Art” is actually generated by a computer. In nearly all cases the computer is used as a new medium for drawing, with the computer not actually contributing to the creative process. There are nice graphics packages which make it much easier for the operator to control the results on the screen, but the process is still quite time consuming. This new approach, which has been a very interesting challenge, is for the program to create its own pictures, using mathematical methods to create the shapes, textures, and arrangements. The program requires a “knowledge” of the subject to be portrayed, i.e. a set of rules about what is a reasonable range for every variable. Not just that, but sets of probabilities for each decision the program might make. You will have seen excellent colour graphics in many Amstrad games. Usually these graphics make extensive use of “user defined” characters, which are rectangular elements (usually 8x8 pixels) used as building blocks. In contrast to this, the use of mathematical functions and probability theory allows us much greater flexibility, enabling the spontaneous creation of different shapes, giving endless surprises, even to the programmer. The simplest form of spontaneous art might rearrange a number of graphic shapes - say to rearrange the positions of a man, a dog, a house, and a tree. But this would soon get boring. To simulate the illusion of “creativity”, we have to use a whole hierarchy of subroutines, which build up the scene from the smallest possible elements, with computer decisions at every level of organisation. In this way a colossal number of arrangements is possible. The possible variations can provide visual effects which will give lasting pleasure, and every time the program is run, a different series of pictures is created. My objective in the Landscape Creator was to have the maximum variety of pictures without contradicting some fundamental facts about landscape structure. The number of calculations involved is astronomical. Just doing a single pixel involves over 50 machine code instructions. Amstrad Basic is very comprehensive and quite fast, but the Landscape Creator has so many calculations to do that machine code is essential. The Amstrad Firmware manual gives the addresses of in-built machine-code routines for plotting. These are easy to use and nicely crashproofed, but the Landscape Creator has its own, even faster plotting routines. Also the arithmetic routines were designed for compactness and speed. The Amstrad has an excellent set of colours for landscapes. Sixteen colours at one time on the screen - chosen from a magnificent 27. Distant hills might be a mysterious grey or light blue, while the foreground might have much brighter colours with yellow or red flowers. Foliage can be a dark green or a bright green. Water can be a mixture of colours reflecting the hills and sky beyond. A white castle looks very smart against rough green forests or black rocks. The precise formulation of the fundamental rules of a landscape is a subjective process depending on the geographical area (or planet) and also depending on the eye of the beholder. This is where the human element comes in -and the inspiration for this task came from the Highlands of Scotland and also the English Lake District. A tremendous advantage of Amstrad graphics is that any pixel can be any colour. You can have 16 colours on screen in Mode 0, with a resolution of 160 pixels horizontally by 200 vertically. For better resolution, Mode 1 gives you 320 horizontally , but only 4 colours. I chose Mode 0 with its much greater range of colours. When I want better resolution horizontally than vertically, I turn the monitor on its side, and swap the x and y axes. Whatever mode you select, any pixel can be any of the available colours. This gives enormous freedom compared with most home computers. When foreground features are drawn they have no interfering effect at all on the background colours. The real beauty of the idea is that you can sit down and relax and enjoy this kaleido-strad of scenes as the Landscape Creator takes you on a voyage of visual delights. For a change you don't need to push any buttons at all. It is an exciting, hi-tech art form which doesn't interfere with conversation like the telly does. And, every time you run the program you see a new set of pictures. If you take a photograph of a particularly striking view, the probability of someone else getting that same view is incredibly small -1 in 1000 million - so in practice, your picture is unique. I am producing the Amstrad Landscape Creator doubly recorded on cassette, or a disc version (for either 464 or 664). Send £5 for the cassette version, or £9 for the disc version, to: G. Brian James, 21 Lamond Place, Aberdeen AB2 3UT, Scotland.
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