Pacman help

[sarah]

I was wondering if anyone could help me figure out how to make my pacman game run properly. I can't get the pacman to stop when he hits a wall, or get him to eat the dots. I've looked through quite a few tutorials and nothing seems to be helping. Any advice at all would really be appriciated.

Here is the code:

code:

View.Set ("graphics;offscreenonly") var x, y : int := 20 var rad : int var key : string (1) var dx, dy : int                % direction Pacman moves         dx := 2                         % Pacman will move to the right         dy := 0                         % Pacman will not be going up or down         x := 30         y := 30         rad := 20 var mouth : int := 1            % size of mouth var dir : int := 0              % mouth direction, 0=right, 90=up, etc. var timeRunning : int var pillx, pilly, pillrad : int pillrad := 5 pillx := 400 pilly := 300 %borders and pacman Draw.FillBox (0,0,10,480,magenta) Draw.FillBox (0,0,640,10,magenta) Draw.FillBox (640,480,0,390,magenta) Draw.FillBox (640,480,630,0, magenta) Draw.FillBox (310,480,330,250,magenta) Draw.FillBox (310,0,330,160,magenta) drawfillarc(x, y, rad, rad, mouth + dir, -mouth + dir, magenta) clock (timeRunning) loop         Draw.FillBox (0,0,10,480,magenta) Draw.FillBox (0,0,640,10,magenta) Draw.FillBox (640,480,0,390,magenta) Draw.FillBox (640,480,630,0, magenta) Draw.FillBox (310,480,330,250,magenta) Draw.FillBox (310,0,330,160,magenta)       drawfilloval (pillx, pilly, pillrad, pillrad, black)     delay (10)               mouth := mouth mod 45 + 1               % change size of the mouth          drawfillarc(x, y, rad, rad, mouth + dir, -mouth + dir, magenta)          delay(10)           x := x + dx                            y := y + dy         View.Update      cls if hasch then getch(key) put "key ", key     if ord(key) = 205 then                  %right arrow         if whatdotcolor (x+20, y+20) not = white then             dx := 0             dy := 0             dir := 0         elsif ord(key) = 205 then             dx := 4             dy := 0             dir := 0         end if     elsif ord(key) = 203  then                 %left arrow         if whatdotcolor (x, y) not = white then             dx := 0             dy := 0             dir := 180         elsif ord(key) = 203 then             dx := -4             dy := 0             dir := 180         end if     elsif ord(key) = 200 then                  %up arrow         if whatdotcolor (x, y) not = white then             dx := 0             dy := 0             dir := 90         elsif ord(key) = 200 then             dx := 0             dy := 4             dir := 90         end if     elsif ord(key) = 208 then                  %down arrow         if whatdotcolor (x, y-20) not = white then             dx := 0             dy := 0             dir := 270         elsif ord(key) = 208 then             dx := 0             dy := -4             dir := 270         end if                      end if           locate (1,1)         if Math.Distance (dx, dy, pillx, pilly) < rad + pillrad then             put "The pacman ate the pill"            else             put "Keep trying!"     end if               end if end loop put "It took you ", timeRunning, " milliseconds to complete the level"

[samuelkyl]

I just started turing, and need to get familiar with it to help your wall question, but for the pill, I could see the problem.

You put dx and dy in the Math.Distance function, change those to x and y, and also, put an exit statement after the "pacman ate the pill". Then move that whole block out of that if statement and right above the end of the loop statement.

Good job with the drawing of the picture, tho. Even though it could be improved, it's pretty creative.
Also check your co-ord +- for your whatdotcolours, some of them are erroneous..

[sarah]

thank you so much. The math.distance works great now

[richcash]

There is a different approach that works great for a game like pacman that is more simplistic. You can use it if you want to make life easier, or stay with your own.

Mentally split the screen up into squares (for example, 10 X 10). In each square, there will be something different. Either it will be a dot, pacman (or a piece of pacman), a piece of a wall, an enemy, or nothing at all. Basically, we can just have a 2 dimensional array represent each of these squares and assign the array elements with 0 for nothing, 1 for pacman, 2 for a dot, 3 for a piece of wall, 4 for an enemy, etc. This way, collision detection becomes so easy, because you can just check if the square pacman is about to move to has a dot, enemy, or wall and act accordingly.

Here is a quick example of what I mean.

Turing:

View.Set ("offscreenonly") var keys : array char of boolean %a 30 X 30 array. each element represents a 10 X 10 square on the screen %0 = nothing, 1 = pacman, 2 = dot, 3 = piece of a wall var grid : array 0 .. 30, 0 .. 30 of int %x, y, is the grid position of pacman var x, y, score := 0 %initialize all grid spaces to 0 for i : 0 .. 30     for j : 0 .. 30         grid (i, j) := 0     end for end for %put some walls in. walls are better hardcoded for n : 10 .. 18     grid (4, n) := 3     grid (5, n) := 3     grid (n + 10, 4) := 3     grid (n + 10, 5) := 3     grid (n, 20) := 3     grid (n, 21) := 3 end for %put some random dots in and make sure they aren't on top of an existing wall for i : 0 .. 30     for j : 0 .. 30         if Rand.Int (1, 100) > 90 and grid (i, j) = 0 then             grid (i, j) := 2         end if     end for end for colour (0) colourback (7) loop     Input.KeyDown (keys)     grid (x, y) := 0     %move pacman unless there's a wall there     if keys (chr (200)) and y < 30 and grid (x, y + 1) not= 3 then         y += 1     elsif keys (chr (208)) and y > 0 and grid (x, y - 1) not= 3 then         y -= 1     elsif keys (chr (205)) and x < 30 and grid (x + 1, y) not= 3 then         x += 1     elsif keys (chr (203)) and x > 0 and grid (x - 1, y) not= 3 then         x -= 1     else         grid (x, y) := 1     end if     %before we delete the dot from the grid array because pacman has got it, put the score up by 10     if grid (x, y) = 2 then         score += 10     end if     %now change delete the dot from the grid array (and replace it with pacman)     grid (x, y) := 1     cls     for i : 0 .. 30         for j : 0 .. 30             %draw depending on what's in the grid space             if grid (i, j) = 1 then                 Draw.FillOval (i * 10 + 5, j * 10 + 5, 5, 5, yellow)             elsif grid (i, j) = 2 then                 Draw.FillOval (i * 10 + 5, j * 10 + 5, 3, 3, white)             elsif grid (i, j) = 3 then                 Draw.FillBox (i * 10, j * 10, i * 10 + 10, j * 10 + 10, red)             end if         end for     end for     put score     View.Update     delay (50) end loop

[tenniscrazy]

I might use that idea for my pacman game im making thanks