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[Sean Raia]

Made this video this morning and then realized how randomly scattered the tips are.

Oh well, give it a watch, maybe you'll learn something new!

 

http://www.youtube.com/watch?v=iok4gK51KGo&feature=youtu.be

[Benearg]

I am total n00b with gamemaker and I appreciate these kinds of tutorials. Now, I don't quite get how to write my own movement scripts, since I learned through code to use vspeed, hspeed and direction, so if you could explain this further would be really useful. I am currently using if X or Y is collision free then jump to x or y (-x or -y). There's anything better than this?
Secondly, I don't get the "floored sprites" technique. Is to avoid bluring pixels?

Anyway, I enjoyed your 2 videos since they are good source for learning.

[Xion]

Benearg; you can define your own speed variables like:

Code:

xspeed = 0;
yspeed = 0;

and then when you want to increment them instead of going hspeed += 1 or whatever you'd go xspeed += 1.
when it comes time to actually move the object you'd just once in the step event do something like

Code:

if place_free(x+xspeed,y+yspeed) {
  x = x+xspeed;
  y = y+yspeed;
  }

That'd actually be a pretty buggy and imprecise way of doing it but the basic idea is present. And now you can make your own collision stuff that's way more accurate than the default gm stuff. You'd probly wanna do something more like

Code:

repeat(abs(xspeed) {
  if place_free(x+sign(xspeed),y)
    x += sign(xspeed);
  else
    xspeed = 0;
  }
repeat(abs(yspeed) {
  if place_free(x,y+sign(yspeed))
    y += sign(yspeed);
  else
    yspeed = 0;
  }

or something, maybe. I think that should work. Possibly.

[Sean Raia]

Im glad you liked the videos!

I was planning on doing a basic top down movement tutorial followed by a platformer movement tutorial this weekend.

[JigsawDisease]

You'd probly wanna do something more like

Code:

repeat(abs(xspeed) {
  if place_free(x+sign(xspeed),y)
    x += sign(xspeed);
  else
    xspeed = 0;
  }
repeat(abs(yspeed) {
  if place_free(x,y+sign(yspeed))
    y += sign(yspeed);
  else
    yspeed = 0;
  }

or something, maybe. I think that should work. Possibly.

wouldnt that code mean you would stop 5 pixels away from an object if you were going at 5 pixels per frame? im a code newbie.

[Rat Casket]

It shouldn't. Sign returns either 1 or -1 regardless of the number its actually looking at.

[JigsawDisease]

ah thanks a lot, i think i might use sign in my own collision detection

[RyanHuggins]

sign(number) is one of the best things I've discovered in GM. Haha. I used to have variables to determine what direction the player was in at any given time (left or right) and now I can just base it on the sign value of the movement.

the max() and min() functions are also super helpful for equilibrium (and setting a speed to its max value or returning it to 0 instead of using a bunch of if statements. These have really cleaned up and condensed my code recently.

As far as the code...

Code:

repeat(ceil(abs(xspeed)))
{
   if (!place_meeting(x + sign(xspeed), y, par_solid)
   {
      x += sign(xspeed);
   }
}

...this is a really functional way to deal with moving objects in a basic way and handling collisions without messy loops to move to contact (or GM's awful function), but some limitations I find is that it's hard/impossible to do movement speeds that aren't integers.

Luckily, gradual increases/decreases in movement still work pretty well, you just can't have an object that moves at 2.5 pixels a step (easily).