Jumping, i've already looked elsewhere =(

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kkun

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Posted: 9th Apr 2010 03:28

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+ Code Snippet

if spacekey() = 1 and jump = 0
   jump =1
endif

if jump = 1
   y2 = y2 + 1
   position object 1, x2, y2, z2
   jump = 0
endif

if spacekey() = 0 and jump = 0
   y2 = y2 - 1
   position object 1, x2, y2, z2
endif


   position object 1, x2, y2, z2
sync
loop

That code there i have is certainly for jump, but when i hold down the spacekey it keeps rising, how do i change that so i cant hold down the key?

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Silvester

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Location: Netherlands

Posted: 9th Apr 2010 09:44 Edited at: 9th Apr 2010 09:45

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Add a trigger to the spacekey, e.g. SpaceKeyPressed.

Add this to the top of your code..

+ Code Snippet

Global SpaceKeyPressed = 0

And then do something like this.

+ Code Snippet

' Activates when the Spacekey is pressed, but we're not yet in Jumpmode.
if spacekey() = 1 and jump = 0
   jump =1
endif

' Activates when Jumpmode is active, but the SpaceKey hasn't been held down for an entire loop before.
if jump = 1 and SpaceKeyPressed = 0
   y2 = y2 + 1
   position object 1, x2, y2, z2
   jump = 0
   SpaceKeyPressed = 1
endif

' Runs when we're out of Jumpmode and the SpaceKey is being held down.
if SpaceKeyPressed = 1 and jump = 0
   y2 = y2 - 1
   position object 1, x2, y2, z2
   SpaceKeyPressed = 0
endif

Note that this method will only let the character jump up ONE coordinate! To let it do more you'll have to change some values and add to the SpaceKeyPressed variable.

EDP Map Editor[2D]

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Van B

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Location: Sunnyvale

Posted: 9th Apr 2010 10:32

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Most people use a Y speed for jumping, so if you imagine the vertical speed as a variable, if it's below 0 then the player is dropping, but with collision you end up with gravity basically.

The main thing is, you have a Y speed, decrease it every loop and add it to the player Y position. If the player collides with the floor, then set their Y speed to -0.1 or something slightly below zero and set their Y position to match the ground height. This is a basic player gravity system, and once it's in place it's very easy to add nice arched jumps - you only need to set the Y speed when the spacekey is pressed, and it sends the player into a jump.

Health, Ammo, and bacon and eggs!

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Hawkblood

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Posted: 9th Apr 2010 19:02

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I've had trouble using a Y speed variable in games before unless you have a constant down-speed. Time-based gravity has a problem when you have different computers having different frame rates and not all frames have the same "time between frames" even on the same computer with a static scene..... Kinda wierd.... I've found that using a parabolic formula or using a sin wave to do the "up" portion works the best.

As far as keeping your character from jumping while still in the air, use Silvester's method..... That's the same type of method I use.

The fastest code is the code never written.

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TheComet

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Posted: 9th Apr 2010 19:27 Edited at: 9th Apr 2010 19:28

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Please... Don't use that method for jumping... It makes the player go up in a linear path and then down in a linear path, and that looks horrible.

What you need is gravity based jumping. Here's an example (I haven't compiled it, so I don't know if it runs or not):

rem setup screen
sync on
sync rate 60
backdrop on
color backdrop 0
hide mouse

rem global variables
global x# as float
global y# as float
global z# as float
global grav# as float
global grav_strength# as float

rem set strength of gravity (play around with this to make it look right)
grav_strength#=0.1

rem set start positions of player
x#=0
y#=10
z#=0

rem make a player
make object cylinder 1,10
color object 1,rgb(0,0,255)
make object collision box 1,-5,-5,-5,5,5,5,0

rem make a ground object
make object box 2,100,5,100
color object 1,rgb(120,40,20)
make object collision box 2,-50,-2.5,-50,50,2.5,50,0

rem main loop
do

rem user info
   center text 320,20,"press space to jump"

rem input
   if spacekey()=1 and grav#=0.0 then grav#=2.0

rem control gravity
   dec grav#,grav_strength#
   inc y#,grav#

rem update positions of player for collision check
   position object 1,x#,y#,z#

rem check for collision with other objects
   if object collision(1,0)
      dec x#,get static collision x()
      dec y#,get static collision y()
      dec z#,get static collision z()
      grav#=0.0
   endif

rem update player positions
   position object 1,x#,y#,z#

rem control camera
   position camera 0,20,-50
   point camera x#,y#,z#

rem refresh screen
   sync

rem end of main loop
loop

rem end
end

+ Code Snippet

rem setup screen
sync on
sync rate 60
backdrop on
color backdrop 0
hide mouse

rem global variables
global x# as float
global y# as float
global z# as float
global grav# as float
global grav_strength# as float

rem set strength of gravity (play around with this to make it look right)
grav_strength#=0.1

rem set start positions of player
x#=0
y#=10
z#=0

rem make a player
make object cylinder 1,10
color object 1,rgb(0,0,255)
make object collision box 1,-5,-5,-5,5,5,5,0

rem make a ground object
make object box 2,100,5,100
color object 1,rgb(120,40,20)
make object collision box 2,-50,-2.5,-50,50,2.5,50,0

rem main loop
do

   rem user info
   center text 320,20,"press space to jump"

   rem input
   if spacekey()=1 and grav#=0.0 then grav#=2.0

   rem control gravity
   dec grav#,grav_strength#
   inc y#,grav#

   rem update positions of player for collision check
   position object 1,x#,y#,z#

   rem check for collision with other objects
   if object collision(1,0)
      dec x#,get static collision x()
      dec y#,get static collision y()
      dec z#,get static collision z()
      grav#=0.0
   endif

   rem update player positions
   position object 1,x#,y#,z#

   rem control camera
   position camera 0,20,-50
   point camera x#,y#,z#

   rem refresh screen
   sync

rem end of main loop
loop

rem end
end

TheComet

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Hawkblood

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Posted: 9th Apr 2010 19:44

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Quote: "It makes the player go up in a linear path and then down in a linear path, and that looks horrible."

It's only linear if you aren't moving....

The fastest code is the code never written.

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Sepnon

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Posted: 9th Apr 2010 19:55

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check if the player is on ground, if it is then jump

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