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Text File | 1991-10-28 | 32KB | 657 lines

LANDSCAPE (c) June 1990 A Fractal scenery generator. Programmed by Andrew Kreibich with AMOSv1.21 (C) 1990 Mandarin/Jawx and compiled with the AMOS compiler. Note: to quit at any time (without using the menu) press Ctrl-C. To save memory this programme closes the workbench while it is running. LANDSCAPE V1.11 docs This doc file applies to the full version. You may have the landscapeDEM version. The only difference between the two is that all saves have been disabled in the DEM version. You can save a lot of calculation time and time spent copying parameters as well as being able to save your pictures by registering. (see DISTRIBUTION, below) ##################### Memory requirements ##################### As it stands the programme probably needs 1 meg. I may work on a version which will run on a 512k machine if I get enough response BUT!:- This programme generates a 256X256 array of points to render the scenes with. The only way I can reduce the memory requirements is to reduce this to a 128X128 array, and this will reduce the maximum resolution of the pictures to resolution setting 2. Purpose: This programme generates Fractal scenery. There are already a few commercial programmes which do this but this is written in AMOS (and is unfortunately a bit slow, although the compiled version is a bit quicker.) It does this by generating a square array of random points and then converting these to heights before plotting them on the screen. I used the midpoint displacement algorithm on page 100 of "The science of fractal images" by Pietgen and Saupe Springer-Verlag 1988 to generate the array of points and the projection and illumination formulae on pages 126 to 128 of the same book to get me started, although all of the routines have been modified many times since I read the book. ################ DISTRIBUTION ################ THIS PROGRAMME IS SHAREWARE! This means that my ego and my wallet would appreciate a little feedback for all my efforts! You may distribute the LandscapeDEM programe to anyone providing you observe the following conditions. (a) You don't make any money from it (apart from a nominal copying fee) without my prior written permission. (b) You may not include it or any routines from it in any commercial release (including SHAREWARE or one of its variations) without my prior written permission. (c) You distribute this entire doc. file file with the programme. (d) You do not distribute the full version of LANDSCAPE to anyone (e) You write back and let me know what you think of it along with a shareware donation. (minimum $20 Australian) To Andrew Kreibich Box 333 Wantirna South Victoria Australia. 3152 When you register (In Australian dollars please, our banks charge a fortune to convert:- another benefit of deregulation?), you will receive the latest compiled version with all features enabled, together with details of other programmes I have written and the source code to this programme (in AMOS). Naturally if you think I have done a really fantastic job on this and you cannot help but show your appreciation by sending more money (Australian Dollars!) etc. then I will happily accept it! If you have the full version and have already registered: Thankyou If you have the full version and have not registered: Pleas do so and may the person who supplied it to you be renedered in the gobberwarts with a blurglecruncheon! USAGE ***** This programme is driven by the menus. There are two stages to drawing a picture. STAGE 1. Calculate the array of data points. Use "Data Points" menu. STAGE 2. Render the data as a picture. Use "Picture" menu. MENUS ***** PROJECT:- ABOUT: try it! LOAD IFF: Loads a picture from disk. I put this in so that you could see all of your creations without having to exit the programme. You can't actually do anything with the picture. This is inactive during CALCULATION and RENDER. SAVE IFF: Saves the current screen to disk. Make sure that none of the message windows are open or they will get saved too! This is inactive during CALCULATION. AND DISABLED IN THE DEM VERSION. ADVERT: Try it! IFSgen is an iterated function system generator. It allows you to generate (and save) IFS codes and produce pictures of self-similar objects (ferns, trees, Sierpinski triangles etc). Fully driven by mouse and menus. The mouse is used to define and manipulate the images. You can save IFS data and IFF picture files of your creations. Many example pictures and IFS code files are included IFSgenV2.0 is shareware and probably requires 1Meg. If you want a demo version of it, all you have to do is write and send me a disk and enough to cover the postage. or $20 for the full version (including source). QUIT: say bye-bye. DATA POINTS:- All items in this menu are to do with generating the array of data points (STAGE 1). (If you haven't got any points then you don't get much of a picture!) The data points are stored in bank 7, To fill this bank with data select CALCULATE from the DATA POINTS menu. This will generate a set of points using the data in the parameters table. A default set of parameters based on a random number seed of 42 is provided so that new users can easily generate a set of points to play with. PARAMETERS: This brings up a table of parameters which you can change to get different sets of data points. RESOLUTION: There are four calculation resolutions 1: Calculates every point in the 256X256 array 2: Calculates every second point. 4: Calculates every fourth point. 8: Calculates every eighth point. The more points you get, the better the resolution of final picture, but more points take longer. The following are typical calculation times when running from AMOS. The compiled version completes these routines about 3½ times as fast. Resolution Time Available plotting resolutions 1 5 min. 1, 2, 4, 8, 16 2 1 min. 15 sec. 2, 4, 8, 16 4 20 sec. 4, 8, 16 8 5 sec. 8, 16 EXTRA RANDOM: ON/OFF If this is on it adds an extra random value to every point after it has calculated the random midpoint displacement (see "The science of fractal images", above) When this is on it has one obvious effect (It takes about twice as long to generate the points) and one not so obvious effect (Without it you sometimes get rows of mountain peaks in a straight line across your picture. Turning it ON reduces the effect). The times above were calculated with this OFF. TO CHANGE VALUES IN THE DARK BROWN BOXES JUST CLICK ON THE BOX WITH THE MOUSE AND START TYPING. DUE TO A SLIGHT PROBLEM WITH THE ROUTINE WHICH HANDLES THE INPUT YOU MAY NOT ALWAYS GET EXACTLY WHAT YOU TYPED! MAKE SURE THAT THE STUFF IN THE BOX IS CORRECT, (YOU CAN USE THE LEFT AND RIGHT CURSORS AND THE DELETE BUTTON OR JUST TYPE OVER THE NUMBERS) AND THEN PRESS RETURN WHEN IT IS OK. FRACTAL PARAMETER: This changes the FRACTAL DIMENSION of the data. The fractal dimension is equal to 3 - fractal parameter. This controls the roughness of the surface. You should normally set this to BETWEEN 0.5 and 1, although any numbers BETWEEN 0 and 1 will do. For a smoother surface set this close to 1, for a rough surface set it a bit lower. Default is 0.85 which seems to work fairly well for most scenes. If you are not sure about this then try a few different values on resolution 1. SEED: This seeds the random number generator. Change this value to get different scenes. *************************** By the way, if you have been playing around with the AMOS random number generator and had trouble regenerating the same sequence of random numbers from the same seed, the following may be of interest. If you use Randomize 42 (or any number) you should (according to the manual) get the same set of random numbers each time. In fact you get a different set (at least with AMOS 1.21) every time, just as if you had used Randomize Timer. If you want the same set each time you must use a negative value for the Rnd function. eg. Rnd (-10) generates a random number between 0 and 10 and you will get the same series of numbers each time you randomize with the same seed. Rnd (10) will generate a random number between 0 and 10 but it will be (truly?) random and does not seem to depend on the seed value. I hope this is of some use, it had me stumped for a while! ************************** ALL DATA (3 buttons) DEFAULT: Returns all settings to their default setting. RESTORE: Returns all settings to what they were before you started fiddling around with them after you chose this menu item. QUIT: Accepts what is in the boxes and returns you to the main screen. LOAD DATA: Loads a bank of data points (and the data parameters) from disk. This is included to save you the trouble of waiting 5-10 minutes (on highest resolution) for the calculation, although with the compiled version you may prefer not to waste the disk space. All data files are suffixed with ".DATABK". SAVE DATA: Saves a bank of data points (and the data parameters) to disk. DISABLED IN THE DEM VERSION. CALCULATE: Calculates the data points using the parameters you specified. If you have not specified then the default values will be used. STOP CALC: Stops the calculation. This could leave you with a data bank which contains a mixture of two sets of data, so either recalculate or load another bank before you render it. Naturally you can only use this while you are CALCULATING and all other menu items will be disabled while you are calculating. PICTURE MENU: All items in this menu are to do with rendering the picture (STAGE 2) PARAMETERS: Brings up a screen of parameters which you can change. Most data is displayed in brown boxes which can be changed in the same way as the data points parameters. RESOLUTION: This is similar to resolution of Data Points, except that there is a 16 button which plots every 16th point. As before small numbers are high resolution. You cannot plot in a higher resolution than the resolution which the data was generated in. Eg. if you generated the data at resolution 4 you can only render in 4, 8 or 16. The other buttons (1 and 2) will be inactive. The main purpose of this is so that you can preview a scene quickly. Typical scene rendering times (using the default data and plotting parameters) and running from AMOS are shown below. The Compiled version takes about 60% of these times for the rendering. The speed improvement is not much because most of the time is taken in the graphics operations (drawing the polygons) and AMOS is already pretty quick at this. Resolution Time 1 35 min. 2 9 min. 4 2.5 min. 8 43 sec. 16 13 sec. VIEW: The 3 parameters in this box define the way the picture is viewed. Elev. Angle: angle of elevation which you view the scene from. Must be between 0 (low view) and 90 (viewed from directly overhead). The actual appearance also depends on the height scale used. Horizon: This is the level of the horizon in pixels measured down from the top of the screen, assuming you are looking at it from zero elevation. Higher elevation angles push the horizon higher up, and the perspective control has a small effect at high elevations as well. Change this to move the picture up and down the screen, the smaller the number the higher the picture. Making this larger can stop the picture finishing before it reaches the bottom of the screen. Perspective: As the picture is generated the points nearest the front are made larger (just like in real life). This parameter controls how much larger. The smaller the number the larger the effect. Typical values lie between 100 and 999. SCALING: The first 3 define the scaling factors used in each direction. Horizontal: Magnifies the picture horizontally. Any number less than about 1.3 will not fill the screen. Vertical: Magnifies the picture vertically. Make this a little bigger if the picture doesn't reach the bottom of the screen. Both Horizontal and Vertical should be above about 1.3 (or else you will get blank bits at the edges) but can get bigger. Height: changes the height of the mountains. Typically 50(low) - 300(high). This Actually determines the maximum THEORETICAL height which could be plotted. In most cases the highest height actually plotted will be less than this because your data points generated in stage 1 will often not reach the maximum possible level. Anyway if you want taller mountains make this bigger. Power: all heights are raised to this power (i.e. h^power) before plotting. This is used to simulate erosion by making the mountains steeper than the valleys. Higher numbers increase this effect. Power must be a whole number >=1, although numbers much bigger than 3 will result in some fairly steep mountains (depending on the height parameter). Usually you will leave this on 3. LEVEL BLEND: These define the level at which trees give way to rocks and rocks to snow and how smooth the transition is. LEVELS: Define the levels of the different colours used. These should be used in conjunction with the Height parameter. I.E. if height is 50 there is little point in setting the sea level at 100 because all of the points would be below sea level. Sea: Sets the sea level. Anything below this height will be plotted in blue, the shade depending on the depth of the water. If you don't want to see any sea then make this low. (i.e. close to zero) Tree: Sets the maximum possible tree level, any point above this will be rendered as rocks or snow. If you don't want trees then set this below sea level. If you want the trees to go right up to the snow then set this greater than or equal to the snow level. Snow: Sets the snow level, any point above this will be rendered as snow. If you don't want snow then make this bigger than height. BLEND: The two blend boxes to the right of the tree and snow level boxes define how quickly the tree and snow will change to rock. Numbers close to zero make the transition sharper (Zero will result in a horizontal line defining the snow and tree levels) while higher numbers (eg 4 or 5) will blend the change over a much larger range. If the tree level is above the snow level (so that there are no rocks) then snow will blend into trees, otherwise both snow and trees will blend into rocks. MAX. ANGLES: These parameters set the maximum steepness for sand, trees and snow. Any slope steeper than this will be rendered as a rock. This is to simulate the fact that snow, sand (and trees) don't stick to very steep surfaces. Each is an angle (between 0 and 90) which measures the maximum possible slope for SAND, TREES and SNOW. (Experiment for best effect) LIGHT SOURCE: These specify the position of the light source (i.e. the sun). Azim: Measures the azimuth (horizontal) angle of the sun (any number from 0 to 360). 0 is left. Some special cases:- 0 or 360 Light from left 90 Light from back 180 Light from right 270 light from front (Yes I know that this is backwards (anticlockwise), but if you knew that then you can probably work out why!) Elev: Measures the elevation of the sun in degrees between 0 (low) and 90 (high). DEFAULT, RESTORE AND QUIT BUTTONS work the same way as those in the data menu. LOAD DATA: loads all the Rendering Data (the stuff in the picture parameters), the Data points Data (seed, resolution Extra random) and the palette from disk. SAVE DATA: saves all the Rendering Data (the stuff in the picture parameters), and Data points data (seed, resolution Extra random) and the palette to disk. DISABLED IN THE DEM VERSION. All Rendering Data files are suffixed with .REND, these files are just sequential data files. RENDER 2D renders a 2 dimensional (contour map) picture of the data. Resolutions of 1 are plotted the same as resolutions of 2 because a full size resolution 1 picture will not quite fit on the screen and it takes ages! This is included so that you can get a rough idea of your scene before you render it. The view is from the middle of the lowest side looking towards the top. The 3D picture will not include the left and right edges of the front because of the perspective. If you want more of the front in then set the PERSPECTIVE PARAMETER to a higher number. Blue areas are below sea level, the darker blue represents deeper water. Areas above sea level are rendered in shades of green, brown and grey/white. Dark green is the lowest and white the highest. In V1.11 I have made no attempt to show tree and snow levels on the 2d plot. The flashing lines show approximately how much will be visible for the parameter settings you have chosen. RENDER 3D Renders a 3 dimensional image using the parameters set up in the picture parameter screen and the data that is currently in the memory. If you haven't generated any data (Stage 1) then you will not get much of a picture. STOP REND Stops the rendering (2D or 3D). Naturally this is inactive unless you are already rendering. You cannot use any of the other items in the picture menu (except PALETTE) or any of the items in the DATA POINTS menu or the LOAD IFF menu item while the picture is rendering. PALETTE Brings up a palette tool in case you don't like the default colours. This is a scaled down version of a general palette tool which I wrote (in AMOS), called Gumby's Palette V1.0. You will get the full procedure (which you can use in your own AMOS programmes) when you register (if you want it: please ask if you do). The landscape version of this procedure supports the following features. DRAGBAR: This is the message (Gumby's Palette) at the top of the screen. Hold left mouse button down while you are over this and drag the palette screen up and down your screen. ABOUT: Work this out for yourself! RGB sliders: These work in the usual way, just click on the slider with the left mouse button and drag it along, or just click on the spot you want it to go to. Up to 32 colours are displayed in little boxes on the right of the screen. You can select two of these at any time. Left mouse button selects the CURRENT colour. This will be changed by moving the slider bars. Right mouse button selects the TO colour. This is used by COPY, SPREAD and CYCLE, to copy, spread or cycle from the current colour to the TO colour, and also by SWAP to swap the current colour with the TO colour. The TO and CURRENT colours are outlined in different colours so that you can see them. It is possible that the colours used by these outlines are hard to see because they are the same or similar to the colour used for the background of the box. COLOUR Buttons: There are 5 of these COPY, SWAP, CYCLE, SPREAD and SKIP. These are selected with the left (and sometimes right) mouse button. COPY and SWAP are explained above. CYCLE. Press Left mouse button to cycle forward and right mouse button to cycle backwards. Cycles all colours between TO and FROM. SPREAD spreads the colour from the current colour to the TO colour and works in conjunction with the SKIP button. If SKIP is 1 then the spread will skip 1 colour in between each one it spreads. Best way is to try it! I put this in because I thought it might be useful in a Mandelbrot type programme. SKIP can be any number you like providing it is between 0 and 9. I don't think it would be a very good idea to set it to a number greater than the number of colours between the two colours you are spreading between. This could cause some unpredictable results. Usually you will leave this set to zero. PALLETE BUTTONS. There are three of these in the original procedure They are SPR, ICON, and DEF. (ICON is new in v1.1) SPR performs a Get Sprite Palette when you click it. The procedure checks to see if there is anything in the sprite bank (bank 1) and if you have no sprites then this button will be inactive. INACTIVE IN LANDSCAPE ICON performs a Get Icon Palette when you click it. The procedure checks to see if there is anything in the icon bank (bank 2) and will render this button inactive if the bank is empty. INACTIVE IN LANDSCAPE DEF Left mouse returns all colours to the programme's default colours. DEF right mouse Returns to the AMOS default colours (which are not much use in landscape!) Exit CANCEL cancels all changes and returns you to your programme. Exit ACCEPT keeps all changes and returns you to your programme. OTHER FEATURES OF LANDSCAPE *************************** DRAGBAR. If you are not rendering, then the entire screen can be dragged up and down by holding down the left mouse button. This feature is inactive during all other menu operations, and only works on the screen which shows the 2D and 3D plots. This has been included because some of the picture is often generated off the monitor screen (the actual screen used is 320 pixels high), and I wanted to see what I had generated without moving the horizon and regenerating the whole thing again. When you let go of the mouse it will return to its usual position. TROUBLESHOOTING *************** If you want to copy a palette from one scene to another then save the source scene as an IFF file and load it into your new scene, then regenerate. If your picture is all sea, then increase the height and/or lower the sea level. If this doesn't help it may be because you have been a silly sod and forgotten to generate any data points! If all of your mountains are very pointy then decrease the height and/or the POWER parameters. (You may also have to decrease the sea level to compensate.) If the sides of your mountains are very smooth and you want to make them rougher then regenerate the data points using a different Fractal Parameter. Make it smaller for rougher terrain. While you are trying to adjust everything for a scene set the resolution on 8 or 16 and render in 2D. When this looks as if it might make something interesting then try it on resolution 16 with 3D. This will allow you to adjust the horizon to get the scene to fill the screen. Use the dragbar to see what you are missing. When it all looks about right then try it on a finer resolution. Sometimes you will generate something which has very high mountains at the front which block out the rest of the picture. These should show up if you render in 2D first. At present the only way around this (assuming you don't like it) is to regenerate the data using a different seed. I hope to do something about this in a later version. ############ BUGS ############ None. (That I know of!) All Bug reports and/or suggestions should be sent to the above address. %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% I hope you find this programme and/or its procedures useful and that you bother to take the time to write back. If you have written anything that you would like to send me, please feel free to do so. BUT PLEASE DON'T SEND ANY SILLY SCROLLY DEMOS, MEGADEMOS, ULTRADEMOS, ULTRAMEGADEMOS, MEGAULTRADEMOS, ULTRACOSMICDEMOS, ALPHAGAMMAOMEGADEMOS, ZAPHODEFFINGBEEBLEBROXDEMOS OR ANYTHING ELSE VAGUELY RESEMBLING A DEMO! AMOS IS A BRILLIANT LANGUAGE SO HOW ABOUT USING IT TO WRITE SOMETHING REALLY USEFUL? Happy (real) programming. Andrew. %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% FUTURE VERSIONS I hope to add the facility to put in roads, lakes and rivers and also to make a few waves around the coastlines. Some clouds and haze if I can make them look good on a lowres screen, (which might be a bit easier in interlace now that I have the amos upgrade that handles it) if not I will try to adapt to hires but this will probably mean slower rendering times and certainly less colours. (Unless I get really ambitious and try a HAM version!) Some other possibilities include: * Rotating the map so that you can view the scene from a different position. (Maybe even the facility to view from any position.) * Flipping the map so that the highest points become low points and the low points high points. * Mouse control of the perspective by changing it on the 2D map. * Interlace option. * Better interface for controlling the parameters. At least one scenery programme that I have heard of generates music while it is rendering. I am not quite sure what the point is but if anyone would like it let me know and I will see what I can do. You tell me, if I have enough time and memory I will do it.