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[AriesT]

Hello dear Game Maker pros,
I bought Game Maker 8 recently and now I'm figuring out how to create Jump n Run game elements. With big help by Alex May, I could set gravity and the controls for a simple square in a small room. I use it like my test room before making a real stage.

Now I have some trouble to shoot for the wall objects, which consist of a simple vertical sprite.



1. When I'm jumping on a free wall element, like you see it in the picture, the square gets stuck. - I guess this has something to do with the gravity but I'm not sure.
2. When I jump next to a wall and holding the arrow key for walking towards it, the square can do kind of a double jump which is not to be intended.
3. The square always stops like 1 or 2 pixels away from the wall and does not touch it directly.

If it helps, here is the STEP events code:

Code:

// Gravity 
// check if in air, step event
if(place_free(x,y+1))
{
    gravity = 0.3; // turn on the gravity
}

if (vspeed >= 12)
{
    vspeed = 12;
}


 // Controls 
  
 if (keyboard_check(vk_left)) 
 { 
     x -= 5; 
 } 
 else if (keyboard_check(vk_right)) 
 { 
     x += 5; 
 } 
  
if (keyboard_check_pressed(vk_space) and !place_free(x,y+1))
{
    vspeed = -8;
}

and the code when colliding with the wall object:

Code:

x += 0;

I hope you pros can help me a bit. I'd appreciate that.

Cheers,
Aries

[AriesT]

Maybe the gmk file helps a lot:

*Click me, I'm jnr.gmk*

[nikki]

not too sure about GM but whats the point of this ? :

x += 0;

[Wizard]

Try this code for size - you are really close to having it cracked but there were a few minor bugs and comments i'd like to make:

1 > You should always put jump before direction, or you get a nasty bug that makes you run off the edge of platforms, and it isn't pretty.
2 > Your wall objects should be solid, or it causes collision bugs.
3 > Your code is looking pretty solid, good work :D

Code:

if place_free(x,y+1) // is there something below me?
{
    gravity = 0.3; // if there's nothing below, gravity on
}else{
    gravity = 0; // if there is something below, gravity off
}

if (vspeed >= 12) // if we're going too fast
{
    vspeed = 12; // let's not go so fast
}

if (keyboard_check_pressed(vk_space) and !place_free(x,y-8))
{
    vspeed = -8;
}

if (keyboard_check(vk_left) and place_free(x-5,y)) // keyboard left, check if there's anything in the way first
{ 
    x -= 5; 
} 
else if (keyboard_check(vk_right) and place_free(x+5,y))  // keyboard right, check if there's anything in the way first
{ 
    x += 5; 
}

And for colliding with walls:-

Code:

y=ceil(y); // makes sure your y co-ord is an integer
move_contact_all(direction,12); // moves the player so it's actually touching the ground
speed = 0; // kills all speed

[AriesT]

Thank you for the quick help.

Now my figure does not jump anymore, when I'm adding your code. If I remove the "!place_free(x,y-8)" part from the jump command, it works but has some flaws touching the wall and the !-boxes (it kind of flickers and does not move straight through it).
I'd like you to have a look at the _real_ gmk (I know I put the .exe in the rar file... )

Maybe you can kill this last bug.

Now I'm a .gmk file!

[Wizard]

Here's a fixed GMK file with a couple tweaks - Your buttons shouldn't be solid or your character won't collide with them properly.

You also don't need to have separate collision events for solid objects, create a solid object then set o_floor_PARENT as it's parent, and the rest is done automagically.

I fixed the jump problem, a big typo by me, sorry!

Download :
http://www.wizardslair.co.uk/dev/jnr.gmk

[AriesT]

It works!
Thanks a lot. Now I can do further research.
E.G. only activating triggers when dodging the buttons from below (like in a Mario game).

Would it bother you if I could be your little padavan as long as I'm learning GM8 and coding basics in general?

[Wizard]

Yeah, sure why not. Add me on MSN(look in my profile) and i'll help where I can.