Math.Distance/Moving on an Arc Problem

[StarGateSG-1]

This require a diagram: see attachment!

A: That is how the line moves along right now.

B: Is how I want to to move, That trouble is I am not sure how, and it has boggled my brain for like 3 days now.

Here is the whole code

code:

% Sets the Screen View.Set ("graphics:640;480,nobuttonbar,offscreenonly") % Declaration of Variables, var x, y, xRadius, yRadius, initialAngle, finalAngle : int := 0 % Values for Trajectory var xAngle, yAngle : int := 0 % Line values var windspeed, Power : int := 0 % Windspeed and power Values var MoveArrow : array char of boolean % Value for when a key has been pressed var Adjust : int % Declaration of Procedures, forward procedure Main forward procedure Trajectory forward procedure MoveTurret % Variable Values, xAngle := maxx - 20 yAngle := 20 % This is the arc distance that needs to be maintain while the % Line moves up and down, var Distance : int := Math.Distance (maxx, 0, yAngle,xAngle) % This is the main procedure which controls the whole program, % Main Program, body procedure Main     % Main loop     loop         % Slows the program down so you have more control over were you palce the turret         delay (50)         % Gets Movemnet from turret         MoveTurret         View.Update         cls     end loop end Main body procedure Trajectory     % Draws the trajectory line     drawarc (x, y, xRadius, yRadius, initialAngle, finalAngle, black) end Trajectory body procedure MoveTurret     % Draws the Turret         drawfilloval (maxx, 0, 20, 20, 7)     drawline (maxx, 0, xAngle, yAngle, black)     % Checks if Up,Down or Enter was pressed     Input.KeyDown (MoveArrow)     % What happens when Up key is pressed     if MoveArrow (KEY_UP_ARROW) then         % If the line is at a 90 then stop it         if xAngle >= 0 and yAngle >= 40 then             xAngle := xAngle             yAngle := yAngle             % Otherwise continue         else             xAngle := xAngle + +1             yAngle := yAngle - -1             % This is for making the line move along a arc pattern             if Math.Distance (maxx, 0, xAngle, yAngle) >= Distance then                 Adjust := Math.Distance (maxx, 0, xAngle, yAngle) - Distance                 yAngle := yAngle - Adjust             else             end if         end if         % What happens when Down key is pressed     elsif MoveArrow (KEY_DOWN_ARROW) then         % If line is at 180 then stop it         if xAngle <= maxx and yAngle <= 0 then             xAngle := xAngle             yAngle := yAngle             % Otherwise continue         else             xAngle := xAngle + -1             yAngle := yAngle - +1             % This is for making the line move along a arc pattern             if Math.Distance (maxx, 0, xAngle, yAngle) >= Distance then             else             end if         end if         % What happens if Enter key is pressed     elsif MoveArrow (KEY_ENTER) then         Trajectory     end if end MoveTurret Main

I could really use some help with this any ideas welcome.

[Cervantes]

You should fix the errors in your code before you post it.

To do this, you need some simple trig, my friend.


Here you go. Study hard.

Turing:

View.Set ("offscreenonly") var timeLast := Time.Elapsed var barrel :     record         angle : real         rotationSpeed : real         length_ : real         endX, endY : real         power : real     end record barrel.angle := 45 barrel.rotationSpeed := 0.2 barrel.length_ := 40 barrel.endX := cosd (barrel.angle) * barrel.length_ barrel.endY := sind (barrel.angle) * barrel.length_ barrel.power := 2 var proj : flexible array 1 .. 0 of     record         x, y, vx, vy : real     end record const gravity := 0.015 var keys : array char of boolean function cooldown (timeDelay : int) : boolean     if Time.Elapsed - timeLast >= timeDelay then         timeLast := Time.Elapsed         result true     end if     result false end cooldown loop     Input.KeyDown (keys)     if keys (KEY_UP_ARROW) then         barrel.angle += barrel.rotationSpeed         barrel.endX := cosd (barrel.angle) * barrel.length_         barrel.endY := sind (barrel.angle) * barrel.length_     end if     if keys (KEY_DOWN_ARROW) then         barrel.angle -= barrel.rotationSpeed         barrel.endX := cosd (barrel.angle) * barrel.length_         barrel.endY := sind (barrel.angle) * barrel.length_     end if     if keys (KEY_ENTER) then         if cooldown (200) then             new proj, upper (proj) + 1             proj (upper (proj)).x := barrel.endX             proj (upper (proj)).y := barrel.endY             proj (upper (proj)).vx := cosd (barrel.angle) * barrel.power             proj (upper (proj)).vy := sind (barrel.angle) * barrel.power         end if     end if     for i : 1 .. upper (proj)         proj (i).vy -= gravity         proj (i).x += proj (i).vx         proj (i).y += proj (i).vy     end for     for i : 1 .. upper (proj)         if proj (i).x > maxx or proj (i).y < 0 or proj (i).x < 0 then             proj (i) := proj (upper (proj))             new proj, upper (proj) - 1             exit         end if     end for     cls     Draw.FillOval (0, 0, 30, 30, black)     Draw.Line (0, 0, round (barrel.endX), round (barrel.endY), black)     for i : 1 .. upper (proj)         Draw.FillOval (round (proj (i).x), round (proj (i).y), 4, 4, black)     end for     View.Update     Time.DelaySinceLast (5) end loop

[StarGateSG-1]

Thank you I will study, its not errors I just forgot to comment.

Edit:

Thank you so much it was right in fornt of me the whole time, I was looking at arc's in the help file, when you search they come up to. I got it working and making mine better by adding more keys and also creating editable factors, gravity and power, you can do kool things with them.