WhatDotColour : MathDistancePointLine

[Guest]

I decided to make a program to test whatdotcolour's collision detection. But I hear people bashing whatdotcolour sometimes and saying learn Math.DistancePointLine (kinda like the main loops and processes). But I looked in the Turing help menu, and that always confuses me. I usually learn by looking at others code and figuring out how it works on my own. Will someone convert this using Math.DistancePointLine. I did look at the Tutorial, but I dont really understand it. Besides, I want a direct comparison between my program and Math.DistancePointLine.

code:

View.Set ("graphics,offscreenonly") Mouse.ButtonChoose ("multibutton") var xMouse, yMouse, button : int var lifter, yLine, x, y := 1 var xBall, yBall := 200 var rad := 10 var line : array 1 .. 2 of int := init (yellow, white) loop     Mouse.Where (xMouse, yMouse, button)     if (rad = 3) then         rad += 1     end if     if (button = 1) then         rad += 1     elsif (button = 10) then         xBall := xMouse         yBall := yMouse     elsif (button = 100) then         rad -= 1     end if     if whatdotcolour (xBall + rad, yBall + rad) = line (1) or             whatdotcolour (xBall + rad, yBall + rad) = line (2) or             whatdotcolour (xBall + rad, yBall - rad) = line (2) or             whatdotcolour (xBall + rad, yBall - rad) = line (2) then         x := -x         y := -y     end if     drawfillbox (0, 0, maxx, maxy, black)     drawline (0, 200, maxx, lifter, line (1))     drawline (maxx, 200, 0, lifter, line (2))     drawfilloval (xBall, yBall, rad, rad, white)     View.Update     lifter += yLine     xBall += x     yBall += y     if (lifter = maxy) then         yLine := -yLine     elsif (lifter = 0) then         yLine := -yLine     end if     if (xBall + rad = maxx) then         x := -x     elsif (xBall - rad = 0) then         x := -x     end if     if (yBall + rad = maxy) then         y := -y     elsif (yBall - rad = 0) then         y := -y     end if end loop

[TheOneTrueGod]

Turing F10 wrote:

Math.DistancePointLine (xp, yp, x1, y1, x2, y2 : real) : real

(xp,yp) is the point that you are checking (Math.DistancePointLine

(x1,y1) is the first point of the line

(x2,y2) is the second point of the line

Now, as it should be obvious, if you have one point, and one line, there are infinitely many ways that you can measure the distance between those two. (Unless the line isn't a line, and is just a point. But then it isn't a line ) So, what mathematicians sp? decided, was that you should try and find the shortest distance between the line and the point. Now, just look at the source code that the Turing F10 gave you (explicitly for your purposes)

code:

% The "Math.DistancePointLine" program. var xp, yp, x1, y1, x2, y2 : int loop     const RADIUS : int := 100     xp := Rand.Int (RADIUS, maxx - RADIUS)     yp := Rand.Int (RADIUS, maxy - RADIUS)     x1 := Rand.Int (0, maxx)     y1 := Rand.Int (0, maxy)     x2 := Rand.Int (0, maxx)     y2 := Rand.Int (0, maxy)     cls     Draw.FillOval (xp, yp, RADIUS, RADIUS, brightred)     Draw.Line (x1, y1, x2, y2, blue)     if Math.DistancePointLine (xp, yp, x1, y1, x2, y2) < RADIUS then         put "The circle touches the line"     else         put "The circle does not touch the line"     end if     delay (2000)     exit when hasch end loop

^^^^^^^^^^^^^^^^^
That is copied directly from the F10 help menu. If you ever do not understand how a command works, just look at the F10 menu. It gives you basically anything you need, from source code to how to use the command written out in words.