slowing down a loop?

Blitz3D Forums/Blitz3D Programming/slowing down a loop?

Sph!nx

(Posted 2008) [#1]

Hi, is there a way to slow down a FOR/NEXT loop? I've tried several things like timers, but the only outcome is that my whole game gets paused.

Anyway, I want it to set the gravity (falling speed) of the player starts at 0 and then count down to -100, yet at a rate I want. The LOOP is instantaneous.

Here is my code :

If Not EntityCollided(player,world_col) Then 

	For i=0 To -100 Step -1

		TranslateEntity player, 0,i, 0

	Next

EndIf

Thanks!

Edit : whoops, I saw I posted this in coding, while it is meant for the beginners area. my apologies...

KillerX

(Posted 2008) [#2]

Use Delay.

Naughty Alien

(Posted 2008) [#3]

you should use timer, and then timer value to decrease/increase falling/jump..on that way you will control motion/time at once..

KillerX

(Posted 2008) [#4]

Also change this to make it more understandable:

If Not EntityCollided(player,world_col) Then 

	For i=0 To 100

		TranslateEntity player, 0,-i, 0

	Next

EndIf

Stevie G

(Posted 2008) [#5]

You should NOT use delay in this situation or a loop. Something like this should work.

Set up a global VelocityY and const Gravity :

global VelocityY# = 0
const Gravity# = 1

Only apply gravity if player has not collided with world :

if entitycollided( player, world_col ) 
     VelocityY# = 0
else
     VelocityY = VelocityY - Gravity
     if VelocityY < -100 VelocityY = -100
endif
translateentity player, 0 , VelocityY, 0

andy_mc

(Posted 2008) [#6]

You run the whole loop as a loop inside the main game loop. Therefore it has to do the internal loop first (going from 0 to -100)
Instead of a for loop, just decrease the players y coord by 1 in each main game loop and check if they get to y=-100 yet to stop them.

Stevie G

(Posted 2008) [#7]

Instead of a for loop, just decrease the players y coord by 1 in each main game loop and check if they get to y=-100 yet to stop them.

Decreasing the players Y coord by 1 is going to simulate a constant downward velocity with no acceleration due to gravity. I don't think this is what he wants judging by his original code.

Ross C

(Posted 2008) [#8]

You could use COS/SIN for an acceleration curve. Then you can work with a linear value, by inputting an angle into SIN/COS and it will produce an increasing/decreasing gap from the last number. ie:

0.001,0.002,0.005,0.013,0.04,0.1,0.4 etc etc

Sph!nx

(Posted 2008) [#9]

Sounds interesting Ross, but still learning this and advanced maths is still a bit to much for me I think.

However, Stevie's suggestion was exactly what I needed! Much appreciated!

Thanks everybody!

andy_mc

(Posted 2008) [#10]

that has to be the most complex way of applying gravity I've ever heard of.

Why not simply watch my gravity tutorial on youtube:
http://www.youtube.com/amcadam26

I explain it in a simple way there.

[/shamless plug]

Sph!nx

(Posted 2008) [#11]

Excellent! I've bookmarked it!