{"id":95,"date":"2015-07-23T17:50:00","date_gmt":"2015-07-23T17:50:00","guid":{"rendered":"https:\/\/therenaissanceraven.com\/?p=95"},"modified":"2015-07-23T17:50:00","modified_gmt":"2015-07-23T17:50:00","slug":"libgdx-camera-work-and-writing-text","status":"publish","type":"post","link":"https:\/\/therenaissanceraven.com\/?p=95","title":{"rendered":"*libGDX* Camera work and Writing Text"},"content":{"rendered":"

In this post we are going to be focusing on creating a camera to view our screen and a very simple act of writing text to appear on screen when touched. First if you are following from the previous post there is something that you will need to change in the main game class:
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    \/\/Public void create() is ran when the program is started.<\/span>
 public<\/span> void<\/span> create<\/span> ()<\/span> {<\/span>
        \/\/Creates the SpriteBatch for gameBatch to use<\/span>
  gameBatch =<\/span> new<\/span> SpriteBatch();<\/span>
        \/\/Creates the font, which is the default font for LIBgdx.<\/span>
  gameFont =<\/span> new<\/span> BitmapFont();<\/span>
        \/\/this will set the screen to our next class \"MainMenuScreen\"<\/span>
        this<\/span>.<\/span>setScreen<\/span>(<\/span>new<\/span> MainMenuScreen(<\/span>this<\/span>));<\/span>
 }<\/span>
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This change is needed so that we may “pass” the SpriteBatch and Font that we made into our game screen so that we can use them. Next in the MainGameScreen Class creating a placeholder to “hold” the game was passed so that we can access it, and creating a camera to view the screen with.
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    \/\/creates a placeholder for the game we are passing (Switch AdlermacGame to name of your Game Class!)<\/span>
    private<\/span> AdlermacGame game;<\/span>

    \/\/Defining the camera to be used<\/span>
    private<\/span> OrthographicCamera camera;<\/span>

    \/\/called upon bein set as a screen (Switch AdlermacGame to name of your Game Class!)<\/span>
    public<\/span> MainMenuScreen<\/span>(<\/span>AdlermacGame game){<\/span>
        \/\/assigns the game we passed to the placeholder<\/span>
        this<\/span>.<\/span>game<\/span>=<\/span>game;<\/span>
        \/\/creates the camera<\/span>
        camera =<\/span> new<\/span> OrthographicCamera();<\/span>
        \/\/Sets the screen to be 800 width by 480 height<\/span>
        camera.<\/span>setToOrtho<\/span>(<\/span>false<\/span>,<\/span>800<\/span>,<\/span>480<\/span>);<\/span>
    }<\/span>
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Next we will be editing the Render method in the MainScreenClass for two reasons, creating a colored background and adding some text. The code is shown and explained below: 
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\/\/this is called every time the game is rendered<\/span>
    @Override<\/span>
    public<\/span> void<\/span> render<\/span>(<\/span>float<\/span> deltaTime){<\/span>
        \/\/Sets the color to be applied after clearing the screen (R,G,B,A)<\/span>
        Gdx.<\/span>gl<\/span>.<\/span>glClearColor<\/span>(<\/span>0<\/span>,<\/span>0<\/span>,<\/span>255<\/span>,<\/span>1<\/span>);<\/span>
        \/\/Clears the screen<\/span>
        Gdx.<\/span>gl<\/span>.<\/span>glClear<\/span>(<\/span>GL20.<\/span>GL_COLOR_BUFFER_BIT<\/span>);<\/span>

        \/\/updates camera view<\/span>
        camera.<\/span>update<\/span>();<\/span>
        \/\/initiates the SpriteBatch from the main Game class<\/span>
        game.<\/span>gameBatch<\/span>.<\/span>begin<\/span>();<\/span>
        \/\/draws the following text with the default font(our batch, text, x, y)<\/span>
        game.<\/span>gameFont<\/span>.<\/span>draw<\/span>(<\/span>game.<\/span>gameBatch<\/span>,<\/span> \"Hey! I'm Text\"<\/span>,<\/span>200<\/span>,<\/span>200<\/span>);<\/span>

        \/\/Code snippet that displays when touched<\/span>
        if<\/span>(<\/span>Gdx.<\/span>input<\/span>.<\/span>isTouched<\/span>()){<\/span>
            game.<\/span>gameFont<\/span>.<\/span>draw<\/span>(<\/span>game.<\/span>gameBatch<\/span>,<\/span> \"and I'm Touched!\"<\/span>,<\/span>500<\/span>,<\/span>200<\/span>);<\/span>
        }<\/span>

        \/\/ends the SpriteBatch<\/span>
        game.<\/span>gameBatch<\/span>.<\/span>end<\/span>();<\/span>

        \/\/displays the deltaTime<\/span>
        System.<\/span>out<\/span>.<\/span>println<\/span>(<\/span>\"deltaTime: \"<\/span> +<\/span> deltaTime);<\/span>
        \/\/shows what the Frames Per Second is<\/span>
        System.<\/span>out<\/span>.<\/span>println<\/span>(<\/span>\"FPS: \"<\/span> +<\/span> 1<\/span>f\/<\/span>deltaTime);<\/span>
    }<\/span>
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This code should display “and im touched!” only when the screen is touched (clicked), upon running you should acheive the following results:<\/p>\n
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  Thus we have now created a way to show text when you desire and also change the background color. This is the end of this tutorial, and for the double checkers or people wanting the hole file, here it is. The final look of the MainMenuScreen:
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package<\/span> com.<\/span>mygdx<\/span>.<\/span>adlermac<\/span>;<\/span>

import<\/span> com.badlogic.gdx.Gdx<\/span>;<\/span>
import<\/span> com.badlogic.gdx.Screen<\/span>;<\/span>
import<\/span> com.badlogic.gdx.graphics.GL20<\/span>;<\/span>
import<\/span> com.badlogic.gdx.graphics.OrthographicCamera<\/span>;<\/span>

public<\/span> class<\/span> MainMenuScreen<\/span> implements<\/span> Screen {<\/span>

    \/\/creates a placeholder for the game we are passing (Switch AdlermacGame to name of your Game Class!)<\/span>
    private<\/span> AdlermacGame game;<\/span>

    \/\/Defining the camera to be used<\/span>
    private<\/span> OrthographicCamera camera;<\/span>

    \/\/called upon bein set as a screen (Switch AdlermacGame to name of your Game Class!)<\/span>
    public<\/span> MainMenuScreen<\/span>(<\/span>AdlermacGame game){<\/span>
        \/\/assigns the game we passed to the placeholder<\/span>
        this<\/span>.<\/span>game<\/span>=<\/span>game;<\/span>
        \/\/creates the camera<\/span>
        camera =<\/span> new<\/span> OrthographicCamera();<\/span>
        \/\/Sets the screen to be 800 width by 480 height<\/span>
        camera.<\/span>setToOrtho<\/span>(<\/span>false<\/span>,<\/span>800<\/span>,<\/span>480<\/span>);<\/span>
    }<\/span>

    \/\/this is called every time the game is rendered<\/span>
    @Override<\/span>
    public<\/span> void<\/span> render<\/span>(<\/span>float<\/span> deltaTime){<\/span>
        \/\/Sets the color to be applied after clearing the screen (R,G,B,A)<\/span>
        Gdx.<\/span>gl<\/span>.<\/span>glClearColor<\/span>(<\/span>0<\/span>,<\/span>0<\/span>,<\/span>255<\/span>,<\/span>1<\/span>);<\/span>
        \/\/Clears the screen<\/span>
        Gdx.<\/span>gl<\/span>.<\/span>glClear<\/span>(<\/span>GL20.<\/span>GL_COLOR_BUFFER_BIT<\/span>);<\/span>

        \/\/updates camera view<\/span>
        camera.<\/span>update<\/span>();<\/span>
        \/\/initiates the SpriteBatch from the main Game class<\/span>
        game.<\/span>gameBatch<\/span>.<\/span>begin<\/span>();<\/span>
        \/\/draws the following text with the default font(our batch, text, x, y)<\/span>
        game.<\/span>gameFont<\/span>.<\/span>draw<\/span>(<\/span>game.<\/span>gameBatch<\/span>,<\/span> \"Hey! I'm Text\"<\/span>,<\/span>200<\/span>,<\/span>200<\/span>);<\/span>

        \/\/Code snippet that displays when touched<\/span>
        if<\/span>(<\/span>Gdx.<\/span>input<\/span>.<\/span>isTouched<\/span>()){<\/span>
            game.<\/span>gameFont<\/span>.<\/span>draw<\/span>(<\/span>game.<\/span>gameBatch<\/span>,<\/span> \"and I'm Touched!\"<\/span>,<\/span>500<\/span>,<\/span>200<\/span>);<\/span>
        }<\/span>

        \/\/ends the SpriteBatch<\/span>
        game.<\/span>gameBatch<\/span>.<\/span>end<\/span>();<\/span>

        \/\/displays the deltaTime<\/span>
        System.<\/span>out<\/span>.<\/span>println<\/span>(<\/span>\"deltaTime: \"<\/span> +<\/span> deltaTime);<\/span>
        \/\/shows what the Frames Per Second is<\/span>
        System.<\/span>out<\/span>.<\/span>println<\/span>(<\/span>\"FPS: \"<\/span> +<\/span> 1<\/span>f\/<\/span>deltaTime);<\/span>
    }<\/span>

    @Override<\/span>
    public<\/span> void<\/span> resize<\/span>(<\/span>int<\/span> width,<\/span> int<\/span> height){<\/span>

    }<\/span>

    @Override<\/span>
    public<\/span> void<\/span> show<\/span>(){<\/span>

    }<\/span>

    @Override<\/span>
    public<\/span> void<\/span> hide<\/span>(){<\/span>

    }<\/span>

    @Override<\/span>
    public<\/span> void<\/span> pause<\/span>(){<\/span>

    }<\/span>

    @Override<\/span>
    public<\/span> void<\/span> resume<\/span>(){<\/span>

    }<\/span>

    @Override<\/span>
    public<\/span> void<\/span> dispose<\/span>(){<\/span>

    }<\/span>
}<\/span>
<\/pre>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n
<\/p>\n","protected":false},"excerpt":{"rendered":"
In this post we are going to be focusing on creating a camera to view our screen and a very simple act of writing text to appear on screen when touched. First if you are following from the previous post there is something that you will need to change in the main game class: 123456789…<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7],"tags":[],"class_list":["post-95","post","type-post","status-publish","format-standard","hentry","category-programming"],"_links":{"self":[{"href":"https:\/\/therenaissanceraven.com\/index.php?rest_route=\/wp\/v2\/posts\/95","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/therenaissanceraven.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/therenaissanceraven.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/therenaissanceraven.com\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/therenaissanceraven.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=95"}],"version-history":[{"count":0,"href":"https:\/\/therenaissanceraven.com\/index.php?rest_route=\/wp\/v2\/posts\/95\/revisions"}],"wp:attachment":[{"href":"https:\/\/therenaissanceraven.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=95"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/therenaissanceraven.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=95"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/therenaissanceraven.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=95"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}