Wall Collision

[Mr. T]

The commented part of code is that which I wish to be helped with. Using whatdotcolour (preferably ), how could I determine if the expanding bars have collided with the outer boundaries that I have drawn. TheOneTrueGod suggested using grid collision, but I wanted to know if there is a whatdotcolour solution.

code:

View.Set ("offscreenonly,nobuttonbar") proc drawBar (barX, barY, a, b : int)     Draw.FillBox (barX, barY, barX + a, barY + 10, red)     Draw.FillBox (barX, barY, barX - b, barY + 10, green) end drawBar var x, y, button, left, middle, right : int := 0 var barX, barY, a, b : int := 0 var boolMoveRed, boolMoveGreen := false loop     View.Update     delay (10)     cls     %Mouse Controls     Mouse.ButtonChoose ("multibutton")     Mouse.Where (x, y, button)     left := button mod 10      % left = 0 or 1     middle := (button - left) mod 100      % middle = 0 or 10     right := button - middle - left      % right = 0 or 100     %Wall Movement Collision     %if %COLLISION WITH RIGHT SIDE OF THE SCREEN then     %   boolMoveRed := false     %end if     %if %COLLISION WITH LEFT SIDE OF THE SCREEN then     %   boolMoveGreen := false     %end if     %Wall Movement Flags     if left = 1 then         barX := x         barY := y         boolMoveRed := true         boolMoveGreen := true     end if     if boolMoveRed = true then         a += 10         drawBar (barX, barY, a, b)     end if     if boolMoveGreen = true then         b += 10         drawBar (barX, barY, a, b)     end if     %Draw Border     Draw.Box (10, 10, maxx - 10, maxy - 10, black) end loop

[Mr. T]

Ok, I managed to solve that problem on my own, but I have a new one. I know it's impossible to pass a flexible array into a procedure through a parameter, so how would I convert my code so that I can draw an increasing # of walls after the first one is complete. I have already gotten a few suggestions from TheOneTrueGod, but I'm still a little bit confused as to how I would implement it in my code.

[Mr. T]

^Read the post above, then look at the code below:

code:

View.Set ("offscreenonly,nobuttonbar") proc drawBar (barX, barY, a, b, colRight, colLeft : int)     Draw.FillBox (barX, barY, barX + a, barY + 10, colRight)     Draw.FillBox (barX, barY, barX - b, barY + 10, colLeft) end drawBar const RADIUS : int := 5 type ballData :     record         x : int         y : int         dx : int         dy : int     end record var ballMovement : flexible array 1 .. 2 of ballData for i : 1 .. upper (ballMovement)     ballMovement (i).x := Rand.Int (RADIUS + 10, maxx - RADIUS - 10)     ballMovement (i).y := Rand.Int (RADIUS + 10, maxy - RADIUS - 10)     ballMovement (i).dx := Rand.Int (-5, 5)     ballMovement (i).dy := Rand.Int (-5, 5) end for var clickX, clickY, button, left, middle, right : int := 0 var barX, barY, a, b, barStoreA, barStoreB : int := 0 var boolMoveRed, boolMoveGreen := false var boolClick := true var topCounter, bottomCounter := 0 loop     View.Update     delay (10)     cls     %Draw Border     Draw.Box (10, 10, maxx - 10, maxy - 10, black)     Draw.Fill (5, 5, black, black)     %Mouse Controls     Mouse.ButtonChoose ("multibutton")     Mouse.Where (clickX, clickY, button)     left := button mod 10      % left = 0 or 1     middle := (button - left) mod 100      % middle = 0 or 10     right := button - middle - left      % right = 0 or 100     %Wall Movement Flags     if left = 1 and boolClick = true and whatdotcolour (clickX, clickY) not= black and whatdotcolour (clickX, clickY) not= blue then         barX := clickX         barY := clickY         boolMoveRed := true         boolMoveGreen := true         boolClick := false     end if     if boolMoveRed = true then         a += 5         barStoreA := barX + a         drawBar (barX, barY, a, b, red, green)     end if     if boolMoveGreen = true then         b += 5         barStoreB := barX - b         drawBar (barX, barY, a, b, red, green)     end if     %Wall Movement Collision     if whatdotcolour (barStoreA + 1, barY) = 7 then         boolMoveRed := false         if boolMoveGreen = false then             drawBar (barX, barY, a, b, blue, blue)         elsif boolMoveGreen = true then             drawBar (barX, barY, a, b, blue, green)         end if     end if     if whatdotcolour (barStoreB - 1, barY) = 7 then         boolMoveGreen := false         if boolMoveRed = false then             drawBar (barX, barY, a, b, blue, blue)         elsif boolMoveRed = true then             drawBar (barX, barY, a, b, red, blue)         end if     end if     %Wall Completion     if whatdotcolour (barStoreA + 1, barY) = 7 and whatdotcolour (barStoreB - 1, barY) = 7 then         %Box Creation Counter (above, below, or none)         for i : 1 .. upper (ballMovement)             if ballMovement (i).y > barY then          %Balls above wall                 topCounter += 1             elsif ballMovement (i).y < barY then      %Balls below wall                 bottomCounter += 1             end if             %Drawing Completed Wall             if topCounter not= 0 and bottomCounter not= 0 then %balls are located ABOVE and BELOW the bar                 %No change             elsif topCounter not= 0 then                %balls are located ABOVE the bar                 Draw.FillBox (10, 10, maxx - 10, barY, blue)             elsif bottomCounter not= 0 then %balls are located BELOW the bar                 Draw.FillBox (10, barY, maxx - 10, maxy - 10, blue)             end if         end for     end if     %Various Ball Collisions     for i : 1 .. upper (ballMovement)         %Balls to Bar Collision (for balls BELOW the bar)         if ballMovement (i).y + RADIUS >= barY and whatdotcolour (ballMovement (i).x, ballMovement (i).y + RADIUS) = blue then             ballMovement (i).dy := -ballMovement (i).dy         end if         %Balls to Bar Collision (for balls ABOVE the bar)         if ballMovement (i).y - RADIUS >= barY and whatdotcolour (ballMovement (i).x, ballMovement (i).y - RADIUS) = blue then             ballMovement (i).dy := -ballMovement (i).dy         end if         %Outer Boundary Collision for Balls         if ballMovement (i).x + ballMovement (i).dx - 10 < RADIUS or                 ballMovement (i).x + ballMovement (i).dx > maxx - 10 - RADIUS then             ballMovement (i).dx := -ballMovement (i).dx         end if         if ballMovement (i).y + ballMovement (i).dy - 10 < RADIUS or                 ballMovement (i).y + ballMovement (i).dy > maxy - 10 - RADIUS then             ballMovement (i).dy := -ballMovement (i).dy         end if         %Change Direction of Balls         ballMovement (i).x := ballMovement (i).x + ballMovement (i).dx         ballMovement (i).y := ballMovement (i).y + ballMovement (i).dy         %Draw Balls         Draw.FillOval (ballMovement (i).x, ballMovement (i).y, RADIUS, RADIUS, black)     end for end loop

[zylum]

you can pass a flexible array to a procedure but you cant change its dimension once in the procedure..

ie:

code:

var arr : flexible array 1 .. 5 of int for i : 1 .. upper (arr)     arr (i) := Rand.Int (1, 9) end for proc printArray (a : array 1 .. * of int)     for i : 1 .. upper (a)         put a (i), " " ..     end for end printArray printArray (arr)

if that doesnt help, can you explain a little further what you need this for?

[Mr. T]

I know...so how would you work around this problem? I will need to update the flexible array.

[Tony]

you could pass a reference to the array using a pointer

[Mr. T]

I didn't understand a single thing you just said. Care to link me to the necessary tutorials?

[Tony]

pointers

part of the Turing Walkthrough actually

[Mr. T]

I read over the tutorial, but I'm still not sure how pointers will allow me to update a flexible array that has been passed into a procedure through a paramater...?