The 2DIY script archive

Actionscript Tutorial No.2

Here's the second in my series of tutorials aimed at helping 2DIY users to use, and understand, actionscript within their creations.

This tutorial deals with creating 'monster' elements that will follow your horizontal position on screen, attempting to stop you passing.

Download 2DIY_tut2

Outline
In a 2DIY platform or maze game, you can make the challenge much harder by placing a monster element on a level that will attempt to stop you from passing by it. This is achieved by the monster following your movements with a slight delay. 

Code Explanation
If you right click on a monster element, you will see the options for how to make the monster element move (the second option). Within this option there is an ‘advanced’ (ADV) setting where you can enter ActionScript code, and here we can set a rule to make the monster follow the horizontal position of the main character (but follow with a slight delay allowing time to pass by).

Tutorial
Create several platforms on screen for a character to jump on and rise up the screen. Place a character at the bottom of the screen, and a monster on the second to top platform. (Each platform layer will need a gap within it for the character to jump up through from the previous layer).

Right click on the monster and look for the animation settings option (the second option). Choose the advanced (ADV) option and  click on the spanner icon* to open the Actionscript help editor. This editor allows you to select the code you need to use in blocks; 

Using the editor you can select the following pieces of code;

 _this (this tells the computer that it will be this element - the monster - to apply the changes to)

._x (this tells the computer the horizontal position along the screen to put the  monster element)

+= (this sets the rule of what the value of x will be)

_root.player._x  (this tells the computer to use the value of the horizontal position of your character) 

- _this._x (this subtracts any difference between the horizontal position of your character and the monster)

/ 16 ( this value can be altered and affects how long the delay is between the position of the character and the monster. The smaller the number, the less the delay in movement)

*If you do not see the spanner icon, you are using an early copy of 2DIY and you will have to type the code in by hand. In this case enter the following;

this._x+= (_root.player._x - this._x) / 16;

Now press the play button, and move your character. You will notice that the monster follows where your character goes, but there is a slight delay. 

What does this do?
You are telling the computer to constantly check the horizontal position of your character, and adjust the position of the monster accordingly to make it follow your characters horizontal position.

Task
Create a platform game with several layers. Each layer needs to have gaps within it to allow your character to leap up and onto the layer above.

Place your character at the bottom of the screen, and a monster on the second to top layer. You could also add additional monsters throughout other layers,  and you will need to add an ‘apple’ element to the top most layer. 

Notes
You could add a completely impassable monster within a game if you wished - maybe combined with the previous tutorial on teleporting - to confuse a player and make them think how solve the problem faced. To make an impassable monster, you would use the code

this._x=_root.player._x;

This tells the computer that whatever the horizontal position of your character (_root.player._x) is, make the monster’s horizontal position (this._x) the same.

You can find out more about this feature in this article

Actionscript Tutorial No.1

Here's the first in what is going to be a whole series of tutorials aimed at helping 2DIY users to use, and understand, actionscript within their creations.

This first tutorial deals with creating 'teleport' hotspots on screen that will make a character instantly jump to a new location.

Download 2DIY_tut1

Outline
In a 2DIY platform or maze game, you can create an interesting effect when your character collides with a monster. Instead of the character losing a life or losing points, you can make the character ‘jump’ to a new location. In this task you are going to make a character jump to a different part of the screen. 

Code Explanation
If you right click on a monster element, you will see the options for what to do during the ‘collision’ between the monster and character (the third option). Within this option there is an ‘advanced’ (ADV) setting where you can enter ActionScript code, and here we can set a rule to make the character move to a new location on the screen by setting the x (horizontal) and y (vertical) positions.

Tutorial
Place a character and a monster on the screen. Right click on the monster and look for the collision settings option (the third option). Choose the advanced (ADV) option and  click on the spanner icon* to open the Actionscript help editor. This editor allows you to select the code you need to use in blocks; 

Using the editor you can select the following pieces of code;

 _root.player (this tells the computer what is going to be affected)

._x or ._y (this tells the computer the position along / down the screen for the action)

= (this sets the rule of what the value of x or y will be)

The final block lets you set the position value of x or y using pixels (see the notes area below for an explanation of the values of both x and y)

*If you do not see the spanner icon, you are using an early copy of 2DIY and you will have to type the code in by hand. In this case enter the following;

_root.player._x=20;

_root.player._y=440;

Now press the play button, move the character onto the monster element and see what happens.

What does this code do?
You are telling the computer that when the character (_root.player) collides with the monster element, the x and y positions of the character are to be changed. This causes the character to jump to that new location instantly. It gives the effect of a ‘teleport’.

Task
Create a platform game with two separate areas on the screen. Place your character in one area, and an ‘apple’ element in the other area. The areas can be separated by using wall elements to block the characters route to an ‘apple’ element. 

You will need to add a monster element within the first area, and change the collision effect so that your character can use it to ‘teleport’ and reach the other side of the screen.

Notes
On the 2DIY screen, the x value is 0 on the left of the screen, and 640 on the right. The y value is 0 at the top of the screen and 480 at the bottom of the screen.

You can find out more about this feature in this article