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Posted: **Sat Aug 09, 2014 1:56 am**

..........

Posted: **Sat Aug 09, 2014 7:01 am**

OK Back, sorry I took so long but there was an interesting Android problem.

So, sticky... I get it.
Here's the deal, once an object (Player) has intersected another object (Wall) it has an overlap of say 1 pixel, I'm sure that isn't accurate but for the sake of imagining the situation lets say it has. No matter which way you want the Player to go the first thing it notices is that it's already intersecting Wall, so... it's first instruction is "If I touch Wall Stop Moving" and it does that and it is shown by the "sticking".

Hermann's Ctrl+ArrowKey is an instruction to ignore intersect all together and the result is no sticking.

Bouncing. This entails that when Player intersects Wall it immediately heads in the opposite direction (note not Stop Moving). If the arrowKey is up and the Player hits a Wall above it then the Player would move down regardless of the arrowKey. The effect if you keep pressing the arrowKey up is Player will "bounce".

chaucer345,
I have no idea what to do with the last code you posted, I made a stack with 4 images and 10 rectangles all named correctly, this line;

Code: Select all

 set the top of line x of characterSprites to the top of line x of characterSprites - playerSpeed

is completely whacked out.
You must use Object Type and Name, the line only has Name.
Craig mentioned this to you already.

Simon

Posted: **Sun Aug 10, 2014 8:34 pm**

Here's the code with improved syntax:

Code: Select all

local myWalls
local characterSprites
local numberOfWalls
local intersectsTop
local intersectsBottom
local intersectsLeft
local intersectsRight
local playerSpeed

on preOpenCard
setUpVariables
end preOpenCard

command setUpVariables
   --set the player looking to the right at startup
   show image "pUp"
   show image "pDown"
   show image "pLeft"
   show image "pRight"
   
   put "pUp" into line 1 of characterSprites
   put "pDown" into line 2 of characterSprites
   put "pLeft" into line 3 of characterSprites
   put "pRight" into line 4 of characterSprites
   
   put 5 into playerSpeed
   
   put 10 into numberOfWalls
   repeat with x = 1 to numberOfWalls
      put "rectangle" & x into line x of myWalls
   end repeat
end setUpVariables

on arrowKey k
   if k = "up" then
      handleWallCollisions
      if intersectsTop = "false" then
      repeat with x = 1 to 4
         set the top of img line x of characterSprites to the top of img line x of characterSprites - playerSpeed
      end repeat
   end if
   else if k = "down" then
      handleWallCollisions
      if intersectsBottom = "false" then
         repeat with x = 1 to 4
            set the bottom of img line x of characterSprites to the bottom of img line x of characterSprites + playerSpeed
         end repeat
         end if
      else if k = "left" then
         handleWallCollisions
         if intersectsLeft = "false" then
            repeat with x = 1 to 4
               set the left of img line x of characterSprites to the left of img line x of characterSprites - playerSpeed
            end repeat
            end if
else if k = "right" then
   handleWallCollisions
   if intersectsRight = "false" then
      repeat with x = 1 to 4
         set the right of img line x of characterSprites to the right of img line x of characterSprites + playerSpeed
      end repeat
      end if
   end if

--reset the collision detection
put false into intersectsBottom
put false into intersectsTop
put false into intersectsLeft
put false into intersectsRight
end arrowKey

--notes where the player has intersected to negate the motion of the player into the wall it will be important to start with all intersections set to false
command handleWallCollisions
   --for every sprite image
   repeat with x = 1 to 4
      --for every wall
      repeat with y = 1 to numberOfWalls
         if intersect (img line x of characterSprites,graphic line y of myWalls, 255) then
            repeat with b = 1 to 4
               if the bottom of img line b of characterSprites > the top of graphic line y of myWalls then 
                  put "true" into intersectsBottom
               end if 
                  if the top of img line b of characterSprites < the bottom of graphic line y of myWalls then
                  put "true" into intersectsTop
               end if
               if the left of img line b of characterSprites  < the right of graphic line y of myWalls then
                  put "true" into intersectsLeft
               end if
               if the right of img line b of characterSprites > the left of graphic line y of myWalls then
                  put "true" into intersectsRight
               end if
               end repeat
            end if
               end repeat
            end repeat
end handleWallCollisions

What the script is supposed to do is first detect whether there's an intersect, then find out whether the right of the sprite intersects it or the left of the sprite intersects it, or the top or the bottom and then only stop the sprite's movement in the direction of the intersection... Though thinking about it I can see part of the problem, that being that this way would make only one direction available to the player.

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Syntax problem, how is then missing in this statement

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Re: Syntax problem, how is then missing in this statement

Re: Syntax problem, how is then missing in this statement