First Project - Lesson 1: Objects
Objects are the most important things in VyScript. Most things are objects in some form, so it is crucial to understand what an object is.

In simplistic terms, an object is a container that holds named variables (you can give them any name you like) and each one points to some type of value. That value can be a number, a string, a boolean, an array, an object, a function, or other various values.

The most basic form of an object takes on the JSON (JavaScript Object Notation) format. When written, a JSON looks something like {"var1": 1, "var2": 2}, where var1 (a variable with a name represented by a string) has the value of 1 and var2 has the value of 2.

While basic objects have a JSON-like format, the object can come in many forms. Below are some examples of a few of those forms.

Note:Do not add any example code to your project unless specifically told to.

{var1: 1, var2: 2} {'var1': 1, 'var2': 2} {"var1": 1, "var2": 2}
Object Types
Basic objects are individual objects that have their own values and do not share any values or have any relationship to other objects. An Object is a special type of object that can be used as a blueprint to create new objects which have default values and share certain properties. An Object has a type in order to identify it. Below is some example code of how we can define our own Object type that is defined as MyObject and has two variables called myVar1 and myVar2 which equal 1 and 2.

MyObject var myVar1 = 1 var myVar2 = 2 Proper indentation is required in VyScript. In order to indent a line, simply insert a tab into the code with the tab key. Each indentation determines the ownership of the line of code. In the code above, both variables have one indentation to show they belong to the MyObject Object. MyObject is the parent of the variables.

Most Objects are allowed to have child types. Children will inherit the properties from all parent Object types. Children will override any property the parent has given them if it has the same one set. Below is some example code of how to create child Object types.

MyObject var myVar1 = 1 var myVar2 = 2 Child1 var myVar1 = 45 var myVar3 = 'child1' Child2 var myVar2 = 54 var myVar3 = 'child2' In the code above we define three Object types, with two of them inheriting properties from a parent. MyObject is the lowest level parent and it gives every child the myVar1 and myVar2 properties. MyObject/Child1 and MyObject/Child2 (Note:when writing Object types, each Object is separated by a forward slash) are the child Objects. MyObject/Child1 overrides its parent's myVar1 with 45 and defines its own myVar3 variable which is a string with the value 'child1'. MyObject/Child2 overrides its parent's myVar2 with 54 and defines its own myVar3 variable which is a string with the value 'child2'.

Note:Putting var  infront of a Object variable definition is optional as long as you provide a value, but it can be helpful to quickly and easily see what the line represents and know for sure that the variable is custom.

Default Object Types
VyScript has some Object types built-in to it to help developers work with the Vylocity engine.

The most important Object is the Diob, which stands for display object. Most engine features require a Diob, so in most cases we will be working with Objects that are or inherit from Diob.

We wont be going over all the different Object types that inherit from Diob in this tutorial, but below is a list of them.


While Diob is the most used, there are a few other built-in Object types. Here is a list of those Objects.


First Project
Now that we understand the basics of Object types, we can set a few properties of one of the built-in ones to make some changes to our project.

Note:If you did not do the first First Project tutorial, be sure to head back and do it first. The rest of this tutorial will assume that it has already been done.

The World Object is the game's main Object. Only one of them exists and the engine creates it for you automatically. It holds variables and functions which are needed to set game (the world) settings and access resources or Objects that exist in the world. One of those settings allows us to set the size of the game window, so that is what we will do first.

Open the main code file in our First Project project and enter the following code.

World gameWidth = 960 gameHeight = 540 This code sets the game's width to 960 pixels and the game's height to 540 pixels.

Note:Built-in Object variables do not have var  included in it's definition.

Because these values are the default sizes for the engine, they wont technically make any difference, so try a few other numbers and then build and run the project to see it in action for yourself. Once you are satisfied, change it back so that we're all on the same page moving forward.

Now we need something to look at other than a black screen. In the previous tutorial we created some icons, but now we need to define some Diobs in the code so we have something to assign our icons to and some things to place down on our map.

As we learned in the previous tutorial, a map is made up of a grid of Tiles. Each coordinate on the map has one Tile and each Tile is a container that holds overlapping Diobs in it's contents. The engine automatically gives each coordinate a Tile so that the developer does not have to (but they can be replaced with a custom Tile if desired). Because of this, we can simply change the default Tile type to give certain properties to every Tile on our map, so add the following code to the bottom of our main code file.

Tile atlasName = 'icons' iconName = 'tile' This code gives every Tile an atlasName of 'icons' and an iconName of 'tile'. We defined these two things when we created our icons icon atlas file. The atlasName is the icon atlas file we want to use and iconName is the name of the icon inside of that icon atlas.

So now we can build our project (Project->Build) and go to the map map file we created in the previous tutorial. Each Tile should now be using the icon we assigned it. If we run the project (Project->Run) we should now see the map using our icons and be able to move the screen around on the map by using the arrow keys or the WASD keys.

Every player that connects to the World is given a Client, and every Client has ownership and control over a player Mob, known as a playerMob. A Mob automatically inherits from Movable (and that automatically inherits from Diob) which allows the Mob to move around on the map and interact with things. If not specified otherwise, every new Client creates a new Mob to act as the playerMob.

Now that the map has a visual representation, let's also give our player a visual representation. Add the following code at the bottom of our main code file.

Mob atlasName = 'icons' iconName = 'player' xCoord = 5 yCoord = 5 This code gives every Mob an atlasName of 'icons', an iconName of 'player', an xCoord of 5, and a yCoord of 5. The xCoord is a Diob's x coordinate on the map and the yCoord is a Diob's y coordinate on the map, starting from the top-left of the map. So our player should be located at 5,5 when it is created, which is 5 Tiles from the top edge of the map and 5 Tiles from the left edge of the map.

Build and run the project and you should now see yourself moving around on the map.

Let's now create some child types.

Change your Mob type definition code to look something like the code below.

Mob atlasName = 'icons' Player iconName = 'player' xCoord = 5 yCoord = 5 Monster iconName = 'monster' Our project now has two new Object types called Mob/Player and Mob/Monster. We will use Mob/Player as our player character and Mob/Monster as a generic monster.

In order for the engine to know that we want the player character to be Mob/Player we will need to define it. This can be done by setting the mainMob variable under World. We simply point it to Mob/Player and every new Client that connects will have a playerMob using our new Mob/Player Object type.

Find your World definition and change it to look like the code below.

World gameWidth = 960 gameHeight = 540 mainMob = 'Mob/Player' Now that we have a monster Mob, we will want to put some Mob/Monster down on our map.

In order for the map editor to know about our new types, we have to build the project. So build the project and then open the map map file.

On the left side of the map editor is a box labeled Diob Types. This is a list of all the Object types that exist in our game that we can place down on our map.

Click on the + in the list that is next to the Mob label to show our two new types. Select Mob/Monster, which will just be labeled Monster, and then place a few of them on the map in the middle of the page by simply clicking.

Build and run the project and as we move around on the map, we should see our monsters, which we are unable to move through because they are dense/solid.

Every Diob has a density variable that determines if things collide with it or not. Any Diob that is a Mob or inherits from it will automatically have a density of 1, which makes it solid.

Mob is meant more for living things in the game, things that might have some sort of intelligence. But we also need things that are used for decoration or maybe just used for simple interactions.

Let's add some new types to our project that we can place on the map for decoration. Add the following code to the bottom of your main code file.

Diob atlasName = 'icons' Solid iconName = 'solid' density = 1 NotSolid iconName = 'not_solid' layer = 20 We now have two new types in our project called Diob/Solid and Diob/NotSolid. As the names indicate, Diob/Solid is solid and Diob/NotSolid is not, however Diob/NotSolid has layer set to 20. The layer variable determines the order of things being drawn onto the screen. Things with higher layers will be drawn after things with lower layers so they will appear above or closer to the viewer.

Mob has a default layer of 4 so our player will move under our Diob/NotSolid.

Build the project and add some of our new types to the map map file. Once done, build again and run the game and then run around the map to see how the engine handles everything.

Before we end this tutorial, let's add some new child types to our Tile definition so we can place down some Tiles that have different appearances.

Find your Tile definition in the main code file and make it look like the code below.

Tile atlasName = 'icons' iconName = 'tile' Grass iconName = 'grass' Dirt iconName = 'dirt' Build the project, open the map map file and place some of our new Tile/Grass and Tile/Dirt on the map. Then build the project again and run it to see the final results of this tutorial in action.

Note:As you place down Tiles you will notice that the one you placed down replaces the old one. This is because each coordinate is designed to have one single Tile which acts as a "floor" for the map visually. You can stack tiles by holding the Shift or Ctrl keys, but it is not recommended unless you only want to add an addition visual thing that is not interacted with.

If you followed everything in this tutorial, the source of your project should look something like this: https://vylocity.com/ide/Vylocity/FirstProject1/

References