----------------------------------- Tony Mon Apr 21, 2003 11:01 pm [source code] Modeling a wave ----------------------------------- Inspired by my physics class and waves unit, I've came up with a short procedure for modeling waves. I will probably be making some apps using this procedure in the future. procedure drawWave(wav,amp:real, move:int) %wav - wave length in pixels :real value %amp - wave amplitude in pixels :real value %move - displacement of wave in pixels horizontaly :int value for i:1 - move ..maxx -move drawline(i+move,round(cos(i/wav*6.3)*amp)+round(maxy/2),i+1+move,round(cos((i+1)/wav*6.3)*amp)+round(maxy/2),black) end for end drawWave In reality its just a cosine graph, modified to allow for accurate wave modeling. This in fact is how all graphs should be done in programming. If you're drawing dots for each X value, you'll have a lot of blank spaces unless your line is perfectly horizontal (or at 45 angle), so you have to draw a line instead. From current point to the next one. Parameters' explanations are commented inside the procedure. Here's a sample of how you call it drawWave(25,20,0) That will draw you a wave with 25 pixel wavelength and 20 pixel amplitude. It is in its original position (moved 0). To find frequency you need to know the time. The frequency is maxx/waveLength/time(in seconds). ----------------------------------- Catalyst Mon Apr 21, 2003 11:36 pm ----------------------------------- i modded your proc a bit so its friendlier with real numbers (i dont like ints) also add a couple more params and made a little prog View.Set ("graphics:640;640,position:300;300,offscreenonly,nobuttonbar") var clr : int for i : 1 .. 256 clr := RGB.AddColor (1, i / 256, 0) end for procedure drawWave (x, y : real, width : real, wav, amp : real, move : real) var count : real := (x - move) var Y : real loop count += 1 Y := round ((cos (count / wav * 6.3) * amp) + y) drawline (round (count + move), round ((cos (count / wav * 6.3) * amp) + y), round (count + 1 + move), round ((cos ((count + 1) / wav * 6.3) * amp) + y), round (((Y / maxy) * 255) + 255)) exit when count >= (x + width) end loop end drawWave var count : real := 10 loop count += 0.1 drawWave (0, maxy / 2, maxx, count / 100, count / 1, round (count)) View.Update drawfillbox (0, 0, maxx, maxy, 7) end loop ----------------------------------- Martin Tue Apr 22, 2003 8:33 pm ----------------------------------- Lookin good guys ----------------------------------- rizzix Sun May 25, 2003 7:57 pm ----------------------------------- heh, guys i've come up with an easier solution! you need to know how to use OO side of turing though... i use a simple convention (cuz i'm kinda limited by turing!!), used all caps for procedure, and all lower-case for functions take note of the equation: y = a(func(k(x - d))) + c where func = (sine, cos or tan) to set the amplitude u call wave_object->A(value) to get the amplitude u call something := wave_object->a to draw the wave u call wave_object->drawWave(border : int, colour : int) to change the scale of degree-to-pixel ratio (default is 1:1 i think) u call wave_object->SCALE(value : real) attached is the wave library file. have fun!!! o btw: dont use the Tangent Wave i haven't completed it yet! but if u insist u can (just remember it gets undefined at 90 degrees) ----------------------------------- rizzix Sun May 25, 2003 8:00 pm hmmm..... ----------------------------------- how do i know i attached the file? i'm new here! thanks.. ----------------------------------- Catalyst Sun May 25, 2003 8:06 pm ----------------------------------- u cant attach files in the source code area ----------------------------------- Catalyst Sun May 25, 2003 8:07 pm ----------------------------------- put it in submissions ----------------------------------- rizzix Sun May 25, 2003 8:09 pm ----------------------------------- ok thx but this should work right?... % y = a(func(k(x - d))) + c class TrigWave export a, A, k, K, d, D, c, C, ix, IX, iy, IY, x1, X1, x2, X2, drawWave, scale, SCALE, LEFT, RIGHT, UP, DOWN, lambda var _a, _k, _d, _c : real % a, k, d, c: of equation var _ix, _iy : int % initial: x and y var _x1, _x2 : int % range/period var _scale : real _scale := 1 _a := 10 _k := 1 _d := 0 _c := 0 _x1 := round (-180 * _scale) _x2 := round (180 * _scale) _ix := round (maxx / 2) _iy := round (maxy / 2) % set/get a fcn a : real result (_a / 10) / _scale end a proc A (_A : real) _a := (_A * 10) * _scale end A % set/get k fcn k : real result _k * _scale end k proc K (_K : real) _k := _K / _scale end K % set/get d fcn d : real result _d / _scale end d proc D (_D : real) _d := _D * _scale end D % set/get c fcn c : real result _c / _scale end c proc C (_C : real) _c := _C * _scale end C % set/get ix fcn ix : int result _ix end ix proc IX (_IX : int) _ix := _IX end IX % set/get iy fcn iy : int result _iy end iy proc IY (_IY : int) _iy := _IY end IY % set/get x1 fcn x1 : int result round (_x1 / _scale) end x1 proc X1 (_X1 : int) _x1 := round (_X1 * _scale) end X1 % set/get x2 fcn x2 : int result round (_x2 / _scale) end x2 proc X2 (_X2 : int) _x2 := round (_X2 * _scale) end X2 % get lambda fcn lambda : real result x2 - x1 end lambda %set/get scale fcn scale : real result _scale end scale proc SCALE (_SCALE : real) var old_scale : real := scale _scale := _SCALE A ((_a / 10) / old_scale) K (_k / old_scale) D (_d / old_scale) C (_c / old_scale) X1 (round (_x1 / old_scale)) X2 (round (_x2 / old_scale)) end SCALE % translate left x units proc LEFT (x : real) D (d - x) end LEFT % translate right x units proc RIGHT (x : real) D (d + x) end RIGHT % translate up x units proc UP (x : real) C (c + x) end UP % translate down x units proc DOWN (x : real) C (c - x) end DOWN % draw the wave deferred proc drawWave (border_width : real, colr : int) end TrigWave class SineWave inherit TrigWave body proc drawWave (border_width : real, colr : int) for x : _x1 .. _x2 drawline (x + ix, round (((_a - border_width) * sind (_k * (x - _d))) + _c) + iy, x + ix, round ((_a * sind (_k * (x - _d - 1))) + _c) + iy, colr) end for end drawWave end SineWave class CosineWave inherit TrigWave body proc drawWave (border_width : real, colr : int) for x : _x1 .. _x2 drawline (x + ix, round (((_a - border_width) * cosd (_k * (x - _d))) + _c) + iy, x + ix, round ((_a * cosd (_k * (x - _d - 1))) + _c) + iy, colr) end for end drawWave end CosineWave class TangentWave inherit TrigWave body proc drawWave (border_width : real, colr : int) for x : _x1 .. _x2 drawline (x + ix, round (((_a - border_width) * cosd (_k * (x - _d))) + _c) + iy, x + ix, round ((_a * cosd (_k * (x - _d - 1))) + _c) + iy, colr) end for end drawWave end TangentWave ----------------------------------- rizzix Sun May 25, 2003 8:14 pm ----------------------------------- here's an example using it! View.Set ("graphics:800;600,offscreenonly,nobuttonbar") var wave2 : ^SineWave new wave2 wave2 -> A(2) wave2 -> SCALE (2) var x : int := 1 loop drawGrid (20) wave2 -> drawWave (5, blue) wave2 -> K (150 - x) wave2 -> C (150 - x) x += 1 if x >= 360 then x := 0 end if delay (20) View.Update cls wave2 -> D (360 - x) put "Scale: ", "1 degree : ", wave2 -> scale, " pixel(s)" put "Range: ", wave2 -> x1, ", ", wave2 -> x2 put "Amplitude: ", wave2 -> a, " x 10" put "horizontal exp: ", wave2 -> k put "Phase Shift: ", wave2 -> d put "Vertical Shift: ", wave2 -> c put "Lambda: ", wave2 -> lambda end loop free wave2 ----------------------------------- rizzix Sun May 25, 2003 8:17 pm ----------------------------------- oh eh almost forgot! proc drawGrid (inc : int) for x : 0 .. maxx by inc drawline (x, 0, x, maxy, grey) end for for y : 0 .. maxy by inc drawline (0, y, maxx, y, grey) end for drawline (0, round (maxy / 2), maxx, round (maxy / 2), red) drawline (round (maxx / 2), 0, round (maxx / 2), maxy, red) end drawGrid to draw a grid ----------------------------------- Catalyst Sun May 25, 2003 10:18 pm ----------------------------------- cool :D ----------------------------------- Tony Sun May 25, 2003 11:16 pm ----------------------------------- looks awesome... just have attach wave parts together to make it solid :wink: ----------------------------------- PHP God Mon May 26, 2003 4:26 pm ----------------------------------- cool sine wave, how bout a sawtooth, or a square, or a sine-square. I'm into electronic music so this crap fascinates me. ----------------------------------- rizzix Mon May 26, 2003 4:53 pm ----------------------------------- oh! ok np simply subtract 1 from _d for y2 in the drawline proc ex: drawline (x + ix, round (((_a - border_width) * sind (_k * (x - _d))) + _c) + iy, x + ix, round ((_a * sind (_k * (x - _d - 1))) + _c) + iy, colr) i fixed the code above... ----------------------------------- rizzix Mon May 26, 2003 5:39 pm ----------------------------------- some additional info... The cool thing about this class is that it defines default values for everything so u can draw a wave by simply writing a few lines.. var wave : ^SineWave new wave wave -> drawWave(0, red) free wave By default: the wave is drawn at centre of screen but the default range is from -180 to 180 thus it technically begins drawing 180 pixels to the left of the middle the scale of the wave is 1:1 (degrees : pixels) setting the scale to 2 doubles the size, length etc, of the wave, yet display the correct values for a,k,d,c,lambda etc.. you can also set it to a value < 1, letting u to display a wave of a larger length. The amplitude of the wave is 10 pixels by default. So setting a to 2 results in an amplitude of 20 pixels you need to specify the thickness of the wave to be drawn, which by default fills the wave from the inside to the very edge. Setting a negative value results in the opposite. And yes the TangentWave is incomplete. Alas, i have no time, so if anyone is interested go ahead and extend the TrigWave class with a complete solution for the TangentWave. I'm currently working on a simple record-base DBMS solution for my ISP in school. Its a success, so far. I've eliminated all those gazillion bugs. It amazingly scalable and flexible. I'll post the complete system here (its not extremely huge, as i said it is quite simple), but only after the ISP. ----------------------------------- Tony Mon May 26, 2003 6:19 pm ----------------------------------- thats cool... And yeah, you should post your ISPs after you hand them in cuz some teachers think that everybody is stupid and just copies code of the net... and if its big, plz upload in file ----------------------------------- brazilian_princess Thu May 29, 2003 9:39 pm ----------------------------------- how do u run that??? *can u tell i suck at comps?* ----------------------------------- krishon Thu May 29, 2003 9:46 pm ----------------------------------- lol, funny avatar ----------------------------------- Homer_simpson Thu May 29, 2003 10:02 pm ----------------------------------- i think her avatar is really nice... ----------------------------------- rizzix Fri May 30, 2003 3:07 pm ----------------------------------- how do u run that??? *can u tell i suck at comps?* well copy all that code into a file... make sure the loop is pasted towards the end of the file the press F1