Multiplatform collision and shorter code.

[Gooie]

I decided a few days ago that It would be a lot easier to make a platformer system right now, and just add to it, rather than reinventing the wheel every time I need a nice movement system. So, I started, I learned about velocity and gravity, also I figured out how to add in a variable friction. I also had a nice plan done for having multiple platforms, to jump on. But, I hit a snag, I have it so that all of the platforms made automatically add their positions to an array of a record to check with when the sprites are figuring out gravity, and collision.

The problem is that if I put the check for ground to disable gravity in a for loop, it allows it through because it only checks one value at a time, I need it to meet all the values at once, for every step of movement. There is probably something obvious here. But I lack the experience to say.

P.S. I realize there are some unfinished systems, and that I do need to check the X values for that platform as well. I just want the Y working first before I move on.

I also wouldn't mind getting ideas for shortening the code. If you have any idea's not matter how fragmented, I'd like to hear them.

Thanks in advanced, any help I get that attributes to a working system I will divide all of my bits amongst all the helpers.

P.P.S. The Sprite can be an AI character of a human, the four players were just a test.

Turing:

var window : int :=     Window.Open ("nobuttonbar, graphics:500;500, offscreenonly") var Key : array char of boolean % These varibales are used to check all Platform X, Y values % with the character X, Y values for gravity collision, and run % collision. var PlatformRecord : flexible array 1 .. 0 of     record         BottomX, TopX, BottomY, TopY : int     end record var SpriteRecord : flexible array 1 .. 0 of     record         Height, Width, PositionX, PositionY : int     end record const GRAVITY := 1 const FRICTION := 1 const AIRRESISTANCE := 3 % Sprite Template class NewSprite     % I/O for class     import Draw, Key, PlatformRecord, GRAVITY, FRICTION, SpriteRecord     export Initialize, Control, Apply, OutputVisual     % Variable Declarations     var PositionX, PositionY, VelocityX, VelocityY,         Height, Width, Density, Mass, Color, Shape,         MovementType, RunSpeed, Acceleration, JumpForce : int := 0     % This should not be called in a loop.     procedure Initialize (PositionX_, PositionY_, Height_, Width_, Color_,             Density_, Shape_, MovementType_, RunSpeed_, JumpForce_ : int)         % Set Values For Class         new SpriteRecord, upper (SpriteRecord) + 1         SpriteRecord (upper (SpriteRecord)).Height := Height_         SpriteRecord (upper (SpriteRecord)).Width := Width_         SpriteRecord (upper (SpriteRecord)).PositionX := PositionX_         SpriteRecord (upper (PlatformRecord)).PositionY := PositionY_         MovementType := MovementType_         Mass := Height_ * Width_         PositionX := PositionX_         PositionY := PositionY_         Density := Density_         Height := Height_         Width := Width_         Color := Color_         Shape := Shape_         RunSpeed := RunSpeed_         JumpForce := JumpForce_     end Initialize     % Based on MovementType entered, each type will be initiated.     procedure Control         /* Movement Types:          0 - Player Controlled (WASD)          1 - Player Controlled (TFGH)          2 - Player Controlled (IJKL)          3 - Player Controlled (Arrow Keys)          */         case MovementType of             label 0 :                 if Key ('d') then                     for i : 1 .. RunSpeed                         VelocityX += 1                     end for                 elsif Key ('a') then                     for i : 1 .. RunSpeed                         VelocityX -= 1                     end for                 end if                 if Key ('w') and                         PlatformRecord (1).TopY = PositionY then                     VelocityY += JumpForce                 end if             label 1 :                 if Key ('h') then                     for i : 1 .. RunSpeed                         VelocityX += 1                     end for                 elsif Key ('f') then                     for i : 1 .. RunSpeed                         VelocityX -= 1                     end for                 end if                 if Key ('t') and                         PlatformRecord (1).TopY = PositionY then                     VelocityY += JumpForce                 end if             label 2 :                 if Key ('l') then                     for i : 1 .. RunSpeed                         VelocityX += 1                     end for                 elsif Key ('j') then                     for i : 1 .. RunSpeed                         VelocityX -= 1                     end for                 end if                 if Key ('i') and                         PlatformRecord (1).TopY = PositionY then                     VelocityY += JumpForce                 end if             label 3 :                 if Key (KEY_RIGHT_ARROW) then                     for i : 1 .. RunSpeed                         VelocityX += 1                     end for                 elsif Key (KEY_LEFT_ARROW) then                     for i : 1 .. RunSpeed                         VelocityX -= 1                     end for                 end if                 if Key (KEY_UP_ARROW) and                         PlatformRecord (1).TopY = PositionY then                     VelocityY += JumpForce                 end if         end case     end Control     % Apply Physics, and Collision to forces and objects.     procedure Apply         if PlatformRecord (1).TopY not= PositionY then             VelocityY -= GRAVITY         end if         for i : 1 .. -VelocityY             if PlatformRecord (1).TopY not= PositionY then                 PositionY -= 1                 if PlatformRecord (1).TopY = PositionY then                     VelocityY := 0                 end if             end if         end for         if VelocityY > 0 then             for i : 1 .. VelocityY                 PositionY += 1             end for         end if         if VelocityX > 0 then             VelocityX -= FRICTION         elsif VelocityX < 0 then             VelocityX += FRICTION         end if         PositionX += VelocityX     end Apply     % Draw Character     procedure OutputVisual         /* Shapes :          0 - Square          1 - Circle          2 - Star          3 - Maple Leaf          4 - Picture (R&D) */         case Shape of             label 0 :                 Draw.FillBox (PositionX - round (Width / 2),                     PositionY, PositionX + round (Width / 2),                     PositionY + Height, Color)             label 1 :                 Draw.FillOval (PositionX, PositionY + round (Height / 2),                     round (Width / 2), round (Height / 2), Color)             label 2 :                 Draw.FillStar (PositionX - round (Width / 2),                     PositionY, PositionX + round (Width / 2),                     PositionY + Height, Color)             label 3 :                 Draw.FillMapleLeaf (PositionX - round (Width / 2),                     PositionY, PositionX + round (Width / 2),                     PositionY + Height, Color)         end case     end OutputVisual end NewSprite % Plateform Template class NewPlatform     % I/O for class     import Draw, PlatformRecord     export Initialize, DrawPlatform     % Variable Declarations     var BottomX, BottomY, TopX, TopY, Color : int     % This should not be called in a loop.     procedure Initialize (BottomX_, BottomY_, TopX_, TopY_, Color_ : int)         new PlatformRecord, upper (PlatformRecord) + 1         PlatformRecord (upper (PlatformRecord)).TopY := TopY_         PlatformRecord (upper (PlatformRecord)).TopX := TopX_         PlatformRecord (upper (PlatformRecord)).BottomX := BottomX_         PlatformRecord (upper (PlatformRecord)).BottomY := BottomY_         TopX := TopX_         TopY := TopY_         BottomX := BottomX_         BottomY := BottomY_         Color := Color_     end Initialize     % This should be called in a loop.     procedure DrawPlatform         Draw.Box (BottomX, BottomY, TopX, TopY, Color)     end DrawPlatform end NewPlatform var Ground : ^NewPlatform new Ground Ground -> Initialize (0, 0, maxx, 100, green) % Create Sprites var Player1, Player2, Player3, Player4 : ^NewSprite new Player1 new Player2 new Player3 new Player4 Player1 -> Initialize (100, 500, 10, 10, red, 4, 2, 0, 4, 15) Player2 -> Initialize (200, 500, 10, 10, blue, 4, 1, 1, 2, 30) Player3 -> Initialize (300, 500, 2, 2, green, 4, 1, 2, 2, 20) Player4 -> Initialize (400, 500, 30, 30, yellow, 4, 1, 3, 2, 15) loop     Input.KeyDown (Key)     Player1 -> Control     Player1 -> Apply     Player1 -> OutputVisual     Player2 -> Control     Player2 -> Apply     Player2 -> OutputVisual     Player3 -> Control     Player3 -> Apply     Player3 -> OutputVisual     Player4 -> Control     Player4 -> Apply     Player4 -> OutputVisual     Ground -> DrawPlatform     View.Update     Draw.Cls     delay (30) end loop

[Clayton]

What should we be using when we have x variables all with the same name, but different numbers at the end of their name?

[Gooie]

Ok, I have been toiling over a hot keyboard for 4 days. Still I have no idea how I'm going to do this. The problem is how I check for collision, I step through the Y Velocity and add 1 or subtract 1 from the Y Position. This is to avoid snapping up when the Velocity is too great and it passes the line. It's like an absolute stop. Here is the code I have a problem with:

Turing:

%GRAVITY         for i : 1 .. upper (PlatformRecord)             if PositionY not= PlatformRecord (i).PositionY then                 OnGround := false                 VelocityY -= 1             else                 OnGround := true             end if         end for         % HANDLES VERTICLE MOVEMENT         for i : 1 .. abs (VelocityY)             if VelocityY > 0 then                 PositionY += 1             elsif VelocityY < 0 then                 PositionY -= 1             end if         end for

How can I check for the values of more than one platform. If it's already in a for loop. I need to combine these sections into one. But, if in that case I would check one at a time. Allowing him to fall for the millisecond its checking another record. But if I keep them separate and use an OnGround Boolean. Then I can't check every position.