I hope more people find your channel. You are the absolute best person on TH-cam. I use what I learn here to make my own dungeon crawler game. I know it's completely different, but things like loading maps still help with making my mini-map. The concepts you provide are useful for other types of games.
A hint if someone was struggling like me. The project was running fine until this video. After i finish it, I tried to run the project but it gave me an error, saying that it couldnt find the Main Class, when previously it always could. Ive search for it throughout the whole internet and tried everything, clean project, change libraries, everything. But nothing worked. When i created a new project and put everything in there, the error persisted. Finally, i found the solution. It was that simple... In the new versions of the libraries, you cannot create the package "object". It was giving me conflict and the project could not run. Change it to objects or obj, or whatever you want. Cheers
I took a break from this project for a bit to finish calc2 but im back, I wanna say again thank you so much for making this. I was curious what your background is, work and education? did you make this tutorial all off the top of your head, how much planning was involved how many iterations of this were there, were there other resources, consultations... I only say this bc it seems like an overwhelming feat for just one person to put this all together. thank you again RyiSnow!
I'm developing my own game (different kind of game, but from scratch in Java). My journey would've been much easier had I been watching these videos over the course of the past year. These videos are top notch. Keep up the good work!
found a hidden gems right here, this is exactly what i need when i tried to find some channels about creating games in java there's rarely seeing them uploading videos like this. Love it, best channel ever!
Thank you so much for all the time and energy you've invested into this series! I can't tell you how much this has helped guide me in making my own game. I always tried to code these features on my own first but when I didn't have a good method for getting things done, your in depth explanation was super helpful! Also, your videos are just really relaxing to watch, it makes coding a lot less stressful haha. Thanks from SF!
This is great, best series yet! I'm developing this for Android so getting everything successfully working up to this point with my knowledge and yours has helped a lot! I would have never thought to use the methods I'm using for game development in this type of gaming! I can't wait to continue, you are a great teacher!
Thank you again for tutorials ^^ When you try to explain something I just get it without any issues ^^ and that mean you are good teacher and you giving multiple ways how to write code I just love that and I rly appreciate!! Wish if everyone would explain stuff like you do!!! Question, do you have any plans to do some other languages like Javascript or PHP or maybe some other orr you explicitly doing Java ^^ ?
Nice tutorials! Keep up the work! It would be really nice to see something like fullscreen mode or changing the screen resolution... You don't have to make it fullscreen, even the new super nintendos have somewhat of an fullscreen where they put the game in the center. So that would work really great too (and give some retro feel)
just wanna say thank you once again for these videos. been following them with my own details here and there and managed to finally complete this one with the collision detection. just had to change a couple of values, and add a couple of classes to my liking and its looking good. thank you!
I'm really enjoying this series. I'm having trouble with the objects not appearing in game. I can only see the one key rendered in game, a second or third will not appear. I cannot see the chest or door objects either. I've been going over the code multiple times, but I can't find any mistakes. Please help!
AH! I love this series! I'm trying to make something out of your tutorials but adding and diverting a lot to make a different game! QUESTION! How do you make different objects of different sizes? Also, how do you layer the sprites so objects and characters can be in front or behind them in certain conditions? (I've only watched till the sound portion of your tutorial since I'm also still composing my own music)
You simply have to make a second modified draw method which can use the object's image size instead of the tileSize. For reference this line of code: graphics2D.drawImage(getObjectTexture(), screenX, screenY, gamePanel.getTILE_SIZE(), gamePanel.getTILE_SIZE(), null); takes 5 parameters (taken from the Graphics Class from java.awt): drawImage(Image img, int x, int y, int width, int height, ImageObserver observer) All you need to do is add a width and height parameter to the object's constructor let's use an example from my game: //======================= // INSTANTIATE VARIABLES //======================= private int width, height; //============= // CONSTRUCTOR //============= public OBJ_Item(String specification, int width, int height) { this.setName(specification); this.width = width; this.height = height; try { setObjectTexture(ImageIO.read(Objects.requireNonNull(getClass().getResourceAsStream("/assets/textures/object/item/" + specification + ".png")))); } catch (IOException e) { Main.LOGGER.error("File IO error: One of the errors couldn't be found due to either reason |" + " " + " 1. The image file name isn't spelled correctly" + " 2. There is a type in the file path, most likely a missing / in front of the assets path"); }//End of Try-Catch }//End of Constructor The logging thing is not required e.printStackTrace can be used, anyways now it's time to make a second version of the draw method overriding the one from your SuperObject inside of the OBJ_Item Class //============================================================================ // OVERRIDDEN METHOD TO DRAW THE OBJECT ON THE SCREEN USING THE OBJECT'S SIZE //============================================================================ @Override public void draw(Graphics2D graphics2D, GamePanel gamePanel) { int screenX = getWorldX() - gamePanel.getPlayer().getWorldX() + gamePanel.getPlayer().getScreenX(); int screenY = getWorldY() - gamePanel.getPlayer().getWorldY() + gamePanel.getPlayer().getScreenY(); //------------------------------------------------------------------------------- // THIS IF STATEMENT IMPROVES PERFORMANCE BY KEEPING OFF-SCREEN TILES NOT DRAWN //------------------------------------------------------------------------------- if (getWorldX() + gamePanel.getTILE_SIZE() > gamePanel.getPlayer().getWorldX() - gamePanel.getPlayer().getScreenX() && getWorldX() - gamePanel.getTILE_SIZE() < gamePanel.getPlayer().getWorldX() + gamePanel.getPlayer().getScreenX() && getWorldY() + gamePanel.getTILE_SIZE() > gamePanel.getPlayer().getWorldY() - gamePanel.getPlayer().getScreenY() && getWorldY() - gamePanel.getTILE_SIZE() < gamePanel.getPlayer().getWorldY() + gamePanel.getPlayer().getScreenY()) { graphics2D.drawImage(getObjectTexture(), screenX, screenY, this.width, this.height, null); }//End of If Statement }//End of Overridden Method }//End of Class Now when you instantiate the object in the AssetSetter class you simply pass in the dimensions of the item. Hope this helps anyone else looking to do this
Great tutorial as always, but I do have one question. I'm not sure if this will be covered later on so I'll just ask: When I want to add an object that is bigger than our tilesize (let's say a tree which is bigger than our player model so maybe 120x120px) how would I be able to do that? Do I need to create another SuperObject class for these objects? thanks for answering in advance and happy new year!~
You don't really need to create another SuperObject. Instead you can scale images to different sizes. I have introduced a different scaling method in Part 11 and scaling to different sizes will be covered in Part 23 that I will upload in a few days. So yes, it will be covered.
00:05 Preparing object images and creating object classes. 03:49 Implementing object key class and loading images in Java game 06:22 Optimally managing object placement in the game for performance improvement 09:01 Setting the object's world position and style 11:58 Drawing objects on the screen using the draw method 14:34 Drawing objects using the draw method in the super object class 17:19 Creating and placing objects in the game 19:54 Implementing object placement for keys, doors, and a chest in a 2D Java game. Crafted by Merlin AI.
I really enjoyed and enjoyed learning your series, but I was a little hesitant because I couldn't understand the logic of the game quickly. Were you like that before?
Amazing tutorials! I got a question though: How would I implement a multi-tile object? Let's say I would like to draw a table and put something on it. I order for the object ON the table to look realistic, the table needs to cover two tiles (let's say half of the lower tile and half of the upper one). An option that would be possible is to create an Object for every part of the table (f.e. OBJ_UpperTable and OBJ_LowerTable) but that seems pretty ugly to me. I've seen people work with multiple layers so the table is implemented on another layer that works half like the tile layer and half like the object layer, but I wouldn't know how to implement that either 🤓 Anyway, I'd love some input! And as I said before: Absolutely amazing content! Keep it up :)
I've never really tried it myself but I think you can draw multiple layered objects by creating another object array. Maybe something like this? // Bottom layer for(int i = 0; i < obj.length; i++) { if(obj[i] != null) { obj[i].draw(g2, this); } } // Second layer for(int i = 0; i < obj2.length; i++) { if(ob2j[i] != null) { ob2j[i].draw(g2, this); } } But if you increase the number of the objects, it might affect the game's performance. I'm not certain until I test it though. If you encounter some lags, drawing them as a background tile is probably better as most of the retro games do (such as A Link to the Past).
@@RyiSnowThanks a lot for replying so quickly! I'll give it a shot and let you know how it worked out :) On another note: I read through the comment section of most of your videos in this series and it's honestly amazing how much time, care and effort you put into helping everyone out! I've rarely seen anything like it and I (and many others) appreciate it so much! I've been subscribed anyway, but I've also shared your channel with friends that might be interested. You really deserve to get those viewers! Anyway, I hope you're doing great and ye, happy holidays (soon) :)
Thanks for the kind words! Replying to comments actually helps me to sort out/review my own knowledge. Also, I often get some nice ideas/suggestions from them so I think it's a win-win situation :) I hope your game will turn out nicely. Happy holidays to you too!
Please try to run the game in debugger and see if the image path and draw method are okay. If not ensure your setObject() method has both world X and worldY. i accidentally used worldX only i faced the same issue as you. Hope this helps. public void setObject() { gp.obj[0] = new OBJ_Key(); gp.obj[0].worldX = 23 * gp.tileSize; gp.obj[0].worldY = 7 * gp.tileSize;
Hello RyiSnow, I've been following your tutorial to create my final project, it's been very helpful but I've encountered a problem... The collisionchecker works fine but after trying to make the item disappear the code encounters an error
What do I do if I didn't want any camera scrolling? Instead of WorldX/Y and ScreenX/Y, I only have x and y, but I don't know how to initialize them for the draw method. My TileManager function basically looks like the one in video #4, not like the one in video #5. UPDATE: I fixed it, I just had to say public void draw(Graphics2D g, GamePanel gp) { int x = *this.x;* int y = *this.y;* g.drawImage(img, x, y, gp.tileSize, gp.tileSize, null); }
Great video as always! But I I've been having a problem, the key does not print, it doesn't give any errors, it's like the key is not there I already tried printing the object without the for loop but it's still not there, can someone help please?
I got some problem, i create an object and whenever i move character down and right , the object is suddenly dissapered.. I don't know how to solve this problem
use Random Class to generate values, in my case, i wanted to generate objects and random positions but the player must be able to reach them(tiles which doesn't have collision property), after the player fetches them that object must be replaced with new one just like in the snake game. so instead of writing gp.obj[0] = new Object_blueRock(); //thats my class name gp.obj[0].obj_x = 11*gp.tileSize; gp.obj[0].obj_y = 4*gp.tileSize; i modify it like this ----------------------------------------------------------------------------------------------------- boolean validPositionFound = false; do { int obj_x = (random.nextInt((int)(gp.screenWidth/gp.tileSize)))*gp.tileSize; int obj_y = (random.nextInt((int)(gp.screenHeight/gp.tileSize)))*gp.tileSize; // Check if the random position is on a tile with number 3 int randomTileNumX = gp.tile.mapT_Num[obj_x / gp.tileSize][obj_y / gp.tileSize]; int randomTileNumY = gp.tile.mapT_Num[obj_x / gp.tileSize][obj_y / gp.tileSize]; // Check the tile below as well if (randomTileNumX == 3 || randomTileNumY == 3) {
} while (!validPositionFound); ----------------------------------------------------------------------------------------------------- and to draw a new one again, inside the method that use to pickup object call the setObject method again : ------------------------------------------------------------------------------------------------------ public void pickupObject(int i) { if(i != 999) { String Object_Name = gp.obj[i].name; switch(Object_Name) { case "rock_lv1": Numrocks++; gp.obj[i] = null; om.setObject(); //newObject
Please try to run the game in debugger and see if the image path and draw method are okay. If not ensure your setObject() method has both world X and worldY. i accidentally used worldX only i faced the same issue as you. Hope this helps. public void setObject() { gp.obj[0] = new OBJ_Key(); gp.obj[0].worldX = 23 * gp.tileSize; gp.obj[0].worldY = 7 * gp.tileSize;
This is a great tutorial! I have 2 questions for trying to make my own code 1.) I want to make objects that can be broken, such as trees or rocks. If there are going to be a lot of these, should I make them tiles or objects? If tiles, how do i create interactions between the player and the tile? 2.) I want to randomize the placement of the trees, however im struggling with trying to get the mapTileNum variable from the TileManager class, so i can check for if it will spawn on water and stop it from happening. Can you help with importing the TileManager variables to the AssetSetter class?
1.) I would do with tiles. You can do that by replacing numbers in mapTileNum. Actually cutting trees will be featured in later part of this series so please stay tuned! 2.) You can access to mapTileNum from AssetSetter by typing gp.tileM.mapTileNum.
Hey I'm currently experiencing some issues on this aspect..the last key isn't coming up and the first key has removed the grass tile and is standing on the earth tile ...any ideas on how I go around this?
@@RyiSnow package Main; import entity.Player; import java.awt.Color; import java.awt.Dimension; import java.awt.Graphics; import java.awt.Graphics2D; import javax.swing.JPanel; import object.SuperObject; import tile.TileManager; public class GamePanel extends JPanel implements Runnable{ //SCREEN SETTNGS final int originalTileSize = 16; //16 x 16 tile final int scale =3; //remove final to make it flexible for ZOOMINOUT public final int tileSize = originalTileSize * scale ; // 48 x48 tile public final int maxScreenCol = 16; public final int maxScreenRow = 12; public final int screenWidth = tileSize * maxScreenCol; // 768 pixels public final int screenHeight = tileSize * maxScreenRow; //576 pixels
//WORLD SETTINGS public final int maxWorldCol = 50; public final int maxWorldRow = 50; public final int worldWidth = tileSize * maxWorldCol; public final int worldHeight = tileSize * maxWorldRow;
//FPS int FPS=60; TileManager tileM = new TileManager(this);
KeyHandler keyH = new KeyHandler();
Thread gameThread; public CollisionChecker cChecker = new CollisionChecker(this); public AssetSetter aSetter = new AssetSetter(this); public Player player= new Player(this,keyH);
Can someone help me? So when we did the KeyHandler I took out the 'elses' and with this I could make my player have free movements, like, I could go diagonally with my player, but now after making collision work my player "lost" the free movements, how can I make it work again?
Hi, do you know anyway of making the object to have an animation when not interacting with it? For example make the key spin. I've tried lots of things but none seem to work
Hi I know I'm very late but you could create multiple images for the key in different orientations and have them change every few frames in the game loop.
I like coding with you RyiSnow! I learn a lot and i try to implement my own stuff here and there as i like. One thing i thought of, regarding this episode. Would it be possible to do the same thing as you did for the tiles but with objects? Read a text file to know where to place the objects. In that way i dont have to go to my code just to change things about my objects! thanks!
Also one thing im trying to do is to change the game panel property "maxWorldCol" and "Row" by reading the file it is about to load and count the rows and colums and set the properties accordenly so i can draw more dynamic worlds in the text files without changin the value in the code
hey I mess something up and I have the following problem Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: Index 16 out of bounds for length 16 at tile.TileManager.loadMap(TileManager.java:119) at tile.TileManager.(TileManager.java:26) at main.GamePanel.(GamePanel.java:46) at main.Main.main(Main.java:16) can you help ; I am stack on this for some time :(
We will implement NPCs in the second half of this series. You can talk to them and get some hints. Also you can buy/sell items with them. I'm not sure what you meant by "make it harder for the gp" though. What kind of stuff is on your mind?
hello again, i wanna say that i have a problem with my collision, so the problem is whenever i pressed down arrow keys and when the character touched the tree, suddenly it got stuck and cannot go up ended by stuck near those trees. Can you help me with that?? Also when i try to send my code in the comment section it always got auto deleted by youtube
Hello, I am experiencing some issues after placing the key in the world. If you could help I would really appreciate and these videos are amazing by the way. So much learned from watching your videos. Thanks!!
Hey Ry, thanks again for all you have done for me on my coding journey as a beginner. Having you as a coach as kept me motivated to stick with Java. I wanted to ask a question. I can get one item to appear but it seems like the code doesn't let me make multiple items because I am unable to see more than one item. I changed the item from key to door to chest and etc. so it isn't the file in IOStream! Please help! -Cal
I made setObject() far better. basically it takes in the name of the object to be set, whether or not it takes collisions, and it's tileX and tileY (i have a function to calculate position in pixel via tileX/Y), then, the function gets the correct image for that object, then places it in the right position. very cool, huh?
gp.object[0] = new object_key(); gp.object[0].worldX = 4 * gp.tileSize; //worldX cannot be resolved??? gp.object[0].worldY = 25 * gp.tileSize; //worldY cannot be resolved?? both ints are public in the object class though & object class is public, with no errors instantiating in the gp, any idea where I went wrong?
I really enjoy your tutorial so far. I am wondering wouldn't it be better to make GameObject abstract, sicne we are repeating some code in Key and Door class. So we could for example have: package nl.xx1.horsebird.object; import lombok.Getter; import lombok.Setter; import nl.xx1.horsebird.GamePanel; import javax.imageio.ImageIO; import java.awt.*; import java.awt.image.BufferedImage; import java.io.IOException; import java.util.Objects; import static nl.xx1.horsebird.GamePanel.TILE_SIZE; @Getter @Setter public abstract class GameObject { private BufferedImage image; private String name; private boolean collision; private int worldX; private int worldY; public abstract String getName(); public GameObject() { try { BufferedImage image = ImageIO.read(Objects.requireNonNull(getClass().getResourceAsStream(String.format("/objects/%s.png", getName())))); setImage(image); } catch (IOException e) { throw new RuntimeException(e); } } public void draw(Graphics2D g2d) { int screenX = worldX - GamePanel.localPlayer.getWorldX() + GamePanel.localPlayer.getScreenX(); int screenY = worldY - GamePanel.localPlayer.getWorldY() + GamePanel.localPlayer.getScreenY(); g2d.drawImage(image, screenX, screenY, TILE_SIZE, TILE_SIZE, null); } } And then we could have a class: package nl.xx1.horsebird.object; import javax.imageio.ImageIO; import java.awt.image.BufferedImage; import java.io.IOException; import java.util.Objects; public class Key extends GameObject{ @Override public String getName() { return "key"; } }
I think we could also improve the code a bit to make some things static in GamePanel so we don't have to pass GamePanel down the road all the time. Let me know what you think about it. Anyway great series!
@@RyiSnow thank you so much for answering, i found the error, it was an old version of a water tile which i wasn't using and it was saved as .gif and not .png. It's my first time coding in java and i started 4 days ago thanks to you
you are the best, been following this tutorial and I feel more and more confident about coding. Thank you for taking out time to make this series.
That's great to hear! Thank you for the comment.
@@RyiSnow My screen is got black any idea
I hope more people find your channel. You are the absolute best person on TH-cam. I use what I learn here to make my own dungeon crawler game. I know it's completely different, but things like loading maps still help with making my mini-map. The concepts you provide are useful for other types of games.
A hint if someone was struggling like me. The project was running fine until this video. After i finish it, I tried to run the project but it gave me an error, saying that it couldnt find the Main Class, when previously it always could. Ive search for it throughout the whole internet and tried everything, clean project, change libraries, everything. But nothing worked. When i created a new project and put everything in there, the error persisted. Finally, i found the solution. It was that simple... In the new versions of the libraries, you cannot create the package "object". It was giving me conflict and the project could not run. Change it to objects or obj, or whatever you want. Cheers
bro you are the best.
saved my life
I took a break from this project for a bit to finish calc2 but im back, I wanna say again thank you so much for making this. I was curious what your background is, work and education? did you make this tutorial all off the top of your head, how much planning was involved how many iterations of this were there, were there other resources, consultations... I only say this bc it seems like an overwhelming feat for just one person to put this all together. thank you again RyiSnow!
I'm developing my own game (different kind of game, but from scratch in Java). My journey would've been much easier had I been watching these videos over the course of the past year. These videos are top notch. Keep up the good work!
found a hidden gems right here, this is exactly what i need when i tried to find some channels about creating games in java there's rarely seeing them uploading videos like this. Love it, best channel ever!
ahhhh why are my comments always got auto deleted by youtube, i just want to send my error codes
Thank you so much for all the time and energy you've invested into this series! I can't tell you how much this has helped guide me in making my own game. I always tried to code these features on my own first but when I didn't have a good method for getting things done, your in depth explanation was super helpful! Also, your videos are just really relaxing to watch, it makes coding a lot less stressful haha. Thanks from SF!
That's great to hear!😄
@@RyiSnow My screen is got black
素晴らしいチュートリアル。君の教えをありがとうございます。
どういたしまして :)
@@RyiSnow My screen is got black
This is great, best series yet! I'm developing this for Android so getting everything successfully working up to this point with my knowledge and yours has helped a lot! I would have never thought to use the methods I'm using for game development in this type of gaming! I can't wait to continue, you are a great teacher!
Thank you again for tutorials ^^
When you try to explain something I just get it without any issues ^^ and that mean you are good teacher and you giving multiple ways how to write code I just love that and I rly appreciate!! Wish if everyone would explain stuff like you do!!!
Question, do you have any plans to do some other languages like Javascript or PHP or maybe some other orr you explicitly doing Java ^^ ?
ty bro youre such a big help hahahahha ive been following the step and create my own condition after i finish your tutorial
Nice tutorials! Keep up the work! It would be really nice to see something like fullscreen mode or changing the screen resolution... You don't have to make it fullscreen, even the new super nintendos have somewhat of an fullscreen where they put the game in the center. So that would work really great too (and give some retro feel)
Yeah I'd love to try this in the full screen too. Maybe I will try that once the game is complete. Thanks for the suggestion.
@@RyiSnow My screen is got black
just wanna say thank you once again for these videos. been following them with my own details here and there and managed to finally complete this one with the collision detection. just had to change a couple of values, and add a couple of classes to my liking and its looking good. thank you!
I'm really enjoying this series. I'm having trouble with the objects not appearing in game. I can only see the one key rendered in game, a second or third will not appear. I cannot see the chest or door objects either. I've been going over the code multiple times, but I can't find any mistakes. Please help!
Very nice. I want to learn how to build something like this from scratch.
Thanks for your game tutorials man.
AH! I love this series! I'm trying to make something out of your tutorials but adding and diverting a lot to make a different game!
QUESTION! How do you make different objects of different sizes? Also, how do you layer the sprites so objects and characters can be in front or behind them in certain conditions? (I've only watched till the sound portion of your tutorial since I'm also still composing my own music)
You simply have to make a second modified draw method which can use the object's image size instead of the tileSize.
For reference this line of code:
graphics2D.drawImage(getObjectTexture(), screenX, screenY, gamePanel.getTILE_SIZE(), gamePanel.getTILE_SIZE(), null);
takes 5 parameters (taken from the Graphics Class from java.awt):
drawImage(Image img, int x, int y, int width, int height, ImageObserver observer)
All you need to do is add a width and height parameter to the object's constructor let's use an example from my game:
//=======================
// INSTANTIATE VARIABLES
//=======================
private int width, height;
//=============
// CONSTRUCTOR
//=============
public OBJ_Item(String specification, int width, int height) {
this.setName(specification);
this.width = width;
this.height = height;
try {
setObjectTexture(ImageIO.read(Objects.requireNonNull(getClass().getResourceAsStream("/assets/textures/object/item/" + specification + ".png"))));
} catch (IOException e) {
Main.LOGGER.error("File IO error: One of the errors couldn't be found due to either reason |" + "
" + "
1. The image file name isn't spelled correctly"
+ "
2. There is a type in the file path, most likely a missing / in front of the assets path");
}//End of Try-Catch
}//End of Constructor
The logging thing is not required e.printStackTrace can be used, anyways now it's time to make a second version of the draw method overriding the one from your SuperObject inside of the OBJ_Item Class
//============================================================================
// OVERRIDDEN METHOD TO DRAW THE OBJECT ON THE SCREEN USING THE OBJECT'S SIZE
//============================================================================
@Override
public void draw(Graphics2D graphics2D, GamePanel gamePanel) {
int screenX = getWorldX() - gamePanel.getPlayer().getWorldX() + gamePanel.getPlayer().getScreenX();
int screenY = getWorldY() - gamePanel.getPlayer().getWorldY() + gamePanel.getPlayer().getScreenY();
//-------------------------------------------------------------------------------
// THIS IF STATEMENT IMPROVES PERFORMANCE BY KEEPING OFF-SCREEN TILES NOT DRAWN
//-------------------------------------------------------------------------------
if (getWorldX() + gamePanel.getTILE_SIZE() > gamePanel.getPlayer().getWorldX() - gamePanel.getPlayer().getScreenX() &&
getWorldX() - gamePanel.getTILE_SIZE() < gamePanel.getPlayer().getWorldX() + gamePanel.getPlayer().getScreenX() &&
getWorldY() + gamePanel.getTILE_SIZE() > gamePanel.getPlayer().getWorldY() - gamePanel.getPlayer().getScreenY() &&
getWorldY() - gamePanel.getTILE_SIZE() < gamePanel.getPlayer().getWorldY() + gamePanel.getPlayer().getScreenY()) {
graphics2D.drawImage(getObjectTexture(), screenX, screenY, this.width, this.height, null);
}//End of If Statement
}//End of Overridden Method
}//End of Class
Now when you instantiate the object in the AssetSetter class you simply pass in the dimensions of the item. Hope this helps anyone else looking to do this
Great tutorial as always, but I do have one question. I'm not sure if this will be covered later on so I'll just ask: When I want to add an object that is bigger than our tilesize (let's say a tree which is bigger than our player model so maybe 120x120px) how would I be able to do that? Do I need to create another SuperObject class for these objects? thanks for answering in advance and happy new year!~
You don't really need to create another SuperObject. Instead you can scale images to different sizes. I have introduced a different scaling method in Part 11 and scaling to different sizes will be covered in Part 23 that I will upload in a few days. So yes, it will be covered.
00:05 Preparing object images and creating object classes.
03:49 Implementing object key class and loading images in Java game
06:22 Optimally managing object placement in the game for performance improvement
09:01 Setting the object's world position and style
11:58 Drawing objects on the screen using the draw method
14:34 Drawing objects using the draw method in the super object class
17:19 Creating and placing objects in the game
19:54 Implementing object placement for keys, doors, and a chest in a 2D Java game.
Crafted by Merlin AI.
I really enjoyed and enjoyed learning your series, but I was a little hesitant because I couldn't understand the logic of the game quickly. Were you like that before?
Amazing tutorials! I got a question though: How would I implement a multi-tile object? Let's say I would like to draw a table and put something on it. I order for the object ON the table to look realistic, the table needs to cover two tiles (let's say half of the lower tile and half of the upper one). An option that would be possible is to create an Object for every part of the table (f.e. OBJ_UpperTable and OBJ_LowerTable) but that seems pretty ugly to me.
I've seen people work with multiple layers so the table is implemented on another layer that works half like the tile layer and half like the object layer, but I wouldn't know how to implement that either 🤓 Anyway, I'd love some input! And as I said before: Absolutely amazing content! Keep it up :)
I've never really tried it myself but I think you can draw multiple layered objects by creating another object array.
Maybe something like this?
// Bottom layer
for(int i = 0; i < obj.length; i++) {
if(obj[i] != null) {
obj[i].draw(g2, this);
}
}
// Second layer
for(int i = 0; i < obj2.length; i++) {
if(ob2j[i] != null) {
ob2j[i].draw(g2, this);
}
}
But if you increase the number of the objects, it might affect the game's performance. I'm not certain until I test it though. If you encounter some lags, drawing them as a background tile is probably better as most of the retro games do (such as A Link to the Past).
@@RyiSnowThanks a lot for replying so quickly! I'll give it a shot and let you know how it worked out :)
On another note: I read through the comment section of most of your videos in this series and it's honestly amazing how much time, care and effort you put into helping everyone out! I've rarely seen anything like it and I (and many others) appreciate it so much! I've been subscribed anyway, but I've also shared your channel with friends that might be interested. You really deserve to get those viewers! Anyway, I hope you're doing great and ye, happy holidays (soon) :)
Thanks for the kind words! Replying to comments actually helps me to sort out/review my own knowledge. Also, I often get some nice ideas/suggestions from them so I think it's a win-win situation :)
I hope your game will turn out nicely. Happy holidays to you too!
how to randomize object placements minding collision with e.g. water?
I copied the tutorial exactly and am unsure why my objects aren't loading, and no errors are being thrown. Anyidea why that could be the case?
Please try to run the game in debugger and see if the image path and draw method are okay. If not ensure your setObject() method has both world X and worldY. i accidentally used worldX only i faced the same issue as you. Hope this helps.
public void setObject() {
gp.obj[0] = new OBJ_Key();
gp.obj[0].worldX = 23 * gp.tileSize;
gp.obj[0].worldY = 7 * gp.tileSize;
gp.obj[1] = new OBJ_Key();
gp.obj[1].worldX = 23 * gp.tileSize;
gp.obj[1].worldY = 40 * gp.tileSize;
}
Thanks you so much for this video!
why whit the zoom the objects move how can i fix it please?
great work, thanks our friend !
Hello RyiSnow, I've been following your tutorial to create my final project, it's been very helpful but I've encountered a problem... The collisionchecker works fine but after trying to make the item disappear the code encounters an error
What do I do if I didn't want any camera scrolling? Instead of WorldX/Y and ScreenX/Y, I only have x and y, but I don't know how to initialize them for the draw method.
My TileManager function basically looks like the one in video #4, not like the one in video #5.
UPDATE: I fixed it, I just had to say
public void draw(Graphics2D g, GamePanel gp) {
int x = *this.x;*
int y = *this.y;*
g.drawImage(img, x, y, gp.tileSize, gp.tileSize, null);
}
Very good. Hope you are well.
Great stuff thanks again
Tool for this : add obj to map(same tool create map), can you create ?
Great video as always! But I I've been having a problem, the key does not print, it doesn't give any errors, it's like the key is not there I already tried printing the object without the for loop but it's still not there, can someone help please?
The collisionOn variable is not updated
After doing this everything is fine except it looks like my player is running at 2x speed also I'm getting shown FPS 60 two times at a time
I got some problem, i create an object and whenever i move character down and right , the object is suddenly dissapered.. I don't know how to solve this problem
I dont any error but the object dont appear on the screen, how can i fix it
pls continue series:) tnx
Thank you very much for your video tutorials)))
Hello mr. Ryisnow can you teach me how to make the character to spawn in random location?
How do you randomize object placement?
use Random Class to generate values, in my case, i wanted to generate objects and random positions but the player must be able to reach them(tiles which doesn't have collision property), after the player fetches them that object must be replaced with new one just like in the snake game.
so instead of writing
gp.obj[0] = new Object_blueRock(); //thats my class name
gp.obj[0].obj_x = 11*gp.tileSize;
gp.obj[0].obj_y = 4*gp.tileSize;
i modify it like this
-----------------------------------------------------------------------------------------------------
boolean validPositionFound = false;
do {
int obj_x = (random.nextInt((int)(gp.screenWidth/gp.tileSize)))*gp.tileSize;
int obj_y = (random.nextInt((int)(gp.screenHeight/gp.tileSize)))*gp.tileSize;
// Check if the random position is on a tile with number 3
int randomTileNumX = gp.tile.mapT_Num[obj_x / gp.tileSize][obj_y / gp.tileSize];
int randomTileNumY = gp.tile.mapT_Num[obj_x / gp.tileSize][obj_y / gp.tileSize]; // Check the tile below as well
if (randomTileNumX == 3 || randomTileNumY == 3) {
gp.obj[0] = new Object_rock();
gp.obj[0].obj_x = obj_x;
gp.obj[0].obj_y = obj_y;
validPositionFound = true;
}
} while (!validPositionFound);
-----------------------------------------------------------------------------------------------------
and to draw a new one again, inside the method that use to pickup object call the setObject method again :
------------------------------------------------------------------------------------------------------
public void pickupObject(int i) {
if(i != 999) {
String Object_Name = gp.obj[i].name;
switch(Object_Name) {
case "rock_lv1":
Numrocks++;
gp.obj[i] = null;
om.setObject(); //newObject
break;
}
}
}
I hope it helps!
Amazing, thanks!
thank you very much, learning a lot :D
My code is the exact same, but doesn't draw the objects. Anyone got the code for this part so I can check against mine?
bru same
check if u put public key instead of public void key
Please try to run the game in debugger and see if the image path and draw method are okay. If not ensure your setObject() method has both world X and worldY. i accidentally used worldX only i faced the same issue as you. Hope this helps.
public void setObject() {
gp.obj[0] = new OBJ_Key();
gp.obj[0].worldX = 23 * gp.tileSize;
gp.obj[0].worldY = 7 * gp.tileSize;
gp.obj[1] = new OBJ_Key();
gp.obj[1].worldX = 23 * gp.tileSize;
gp.obj[1].worldY = 40 * gp.tileSize;
}
@@HABIBMUHD92 Thank you. I managed to figure it out.
Amazing! :D
What is the application u are using for drawing objects?
Gimp and Piskel
This is a great tutorial! I have 2 questions for trying to make my own code
1.) I want to make objects that can be broken, such as trees or rocks. If there are going to be a lot of these, should I make them tiles or objects? If tiles, how do i create interactions between the player and the tile?
2.) I want to randomize the placement of the trees, however im struggling with trying to get the mapTileNum variable from the TileManager class, so i can check for if it will spawn on water and stop it from happening. Can you help with importing the TileManager variables to the AssetSetter class?
1.) I would do with tiles. You can do that by replacing numbers in mapTileNum. Actually cutting trees will be featured in later part of this series so please stay tuned!
2.) You can access to mapTileNum from AssetSetter by typing gp.tileM.mapTileNum.
@@RyiSnow thank you so much! I'll make sure to look out for future tutorials, then.
Hey I'm currently experiencing some issues on this aspect..the last key isn't coming up and the first key has removed the grass tile and is standing on the earth tile ...any ideas on how I go around this?
May I see your Player class and CollisionChecker class?
@@RyiSnow any social media I can reach you on?
You can paste the code here!
@@RyiSnow package Main;
import entity.Player;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import javax.swing.JPanel;
import object.SuperObject;
import tile.TileManager;
public class GamePanel extends JPanel implements Runnable{
//SCREEN SETTNGS
final int originalTileSize = 16; //16 x 16 tile
final int scale =3;
//remove final to make it flexible for ZOOMINOUT
public final int tileSize = originalTileSize * scale ; // 48 x48 tile
public final int maxScreenCol = 16;
public final int maxScreenRow = 12;
public final int screenWidth = tileSize * maxScreenCol; // 768 pixels
public final int screenHeight = tileSize * maxScreenRow; //576 pixels
//WORLD SETTINGS
public final int maxWorldCol = 50;
public final int maxWorldRow = 50;
public final int worldWidth = tileSize * maxWorldCol;
public final int worldHeight = tileSize * maxWorldRow;
//FPS
int FPS=60;
TileManager tileM = new TileManager(this);
KeyHandler keyH = new KeyHandler();
Thread gameThread;
public CollisionChecker cChecker = new CollisionChecker(this);
public AssetSetter aSetter = new AssetSetter(this);
public Player player= new Player(this,keyH);
public SuperObject obj[]=new SuperObject[10];
public GamePanel(){
this.setPreferredSize(new Dimension(screenWidth, screenHeight));
this.setBackground(Color.black);
this.setDoubleBuffered(true);
this.addKeyListener(keyH);
this.setFocusable(true);
}
public void setupGame(){
aSetter.setObject();
}
public void startGameThread(){
gameThread = new Thread(this);
gameThread.start();
}
public void run(){
double drawInterval = 1000000000/FPS;
double delta= 0;
long lastTime =System.nanoTime();
long currentTime;
long timer = 0;
int drawCount = 0;
while (gameThread != null){
currentTime = System.nanoTime();
delta+= (currentTime - lastTime)/ drawInterval;
timer +=(currentTime - lastTime);
lastTime = currentTime;
if(delta >=1){
update();
repaint();
delta--;
drawCount++;
}
if(timer >= 1000000000){
System.out.println("FPS:" + drawCount);
drawCount = 0;
timer = 0;
}
}
}
public void update(){
player.update();
}
public void paintComponent(Graphics g){
super.paintComponent(g);
Graphics2D g2 = (Graphics2D)g;
//TILE
tileM.draw(g2);
//OBJECT
for(int i =0; i < obj.length;i++){
if(obj[i] != null){
obj[i].draw(g2, this);
}
}
//PLAYER
player.draw(g2);
g2.dispose();
}
}
That's GamePanel class.
Can someone help me? So when we did the KeyHandler I took out the 'elses' and with this I could make my player have free movements, like, I could go diagonally with my player, but now after making collision work my player "lost" the free movements, how can I make it work again?
you have to make collisions with your diaganal movements... do it like you did with the up down left and right movements..
Hi,
do you know anyway of making the object to have an animation when not interacting with it? For example make the key spin. I've tried lots of things but none seem to work
Hi I know I'm very late but you could create multiple images for the key in different orientations and have them change every few frames in the game loop.
I like coding with you RyiSnow! I learn a lot and i try to implement my own stuff here and there as i like. One thing i thought of, regarding this episode.
Would it be possible to do the same thing as you did for the tiles but with objects? Read a text file to know where to place the objects. In that way i dont have to go to my code just to change things about my objects!
thanks!
Also one thing im trying to do is to change the game panel property "maxWorldCol" and "Row" by reading the file it is about to load and count the rows and colums and set the properties accordenly so i can draw more dynamic worlds in the text files without changin the value in the code
Thanks!
hey I mess something up and I have the following problem
Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: Index 16 out of bounds for length 16
at tile.TileManager.loadMap(TileManager.java:119)
at tile.TileManager.(TileManager.java:26)
at main.GamePanel.(GamePanel.java:46)
at main.Main.main(Main.java:16)
can you help ; I am stack on this for some time :(
Did you expand the size of mapTileNum to maxWorldCol and maxWorldRow so it can contain the world map?
@@RyiSnow yes
@@RyiSnowI found the problem catch (IOException e) it was supposed to be catch (Exception e)
Hey im having an issue. Everytime i add gamePanel.setupGame();. my player does not move
probably when you created the "objects" package, you put "object" or something different from what you typed when searching for the image.
Thanks
Nice
Some ide from me
Could you make a guide to implant NPCs that could make it harder for the gp in their quest
We will implement NPCs in the second half of this series. You can talk to them and get some hints. Also you can buy/sell items with them. I'm not sure what you meant by "make it harder for the gp" though. What kind of stuff is on your mind?
@@RyiSnow yes it Was that, thanks for a good tutorial
@@RyiSnow My screen is got black
Why you multiplicate the position of object for "gp.tilseSize" ?
Because we need to get its x and y.
@@RyiSnow My screen is got black
For some reason I cannot place more than one object of a type.
can you also make a tutorial on how to make a 3d game
hello again, i wanna say that i have a problem with my collision, so the problem is whenever i pressed down arrow keys and when the character touched the tree, suddenly it got stuck and cannot go up ended by stuck near those trees. Can you help me with that?? Also when i try to send my code in the comment section it always got auto deleted by youtube
It happens only when you go down?
@@RyiSnow yes sir
Can I do this project on Intellij IDE?
of course
I'm getting this exception how do I deal with it?? Exception in thread "main" java.lang.IllegalArgumentException: input == null!
Hello, I am experiencing some issues after placing the key in the world. If you could help I would really appreciate and these videos are amazing by the way. So much learned from watching your videos. Thanks!!
did you find out how to solve it?
Cool Bro. I subscribed.
Hey Ry, thanks again for all you have done for me on my coding journey as a beginner. Having you as a coach as kept me motivated to stick with Java.
I wanted to ask a question. I can get one item to appear but it seems like the code doesn't let me make multiple items because I am unable to see more than one item. I changed the item from key to door to chest and etc. so it isn't the file in IOStream!
Please help!
-Cal
How to make the game multiplayer
online
no can do my guy....
bc idk how
Can you make a 3D game(or you can't do that)
You can checkout thinmatrix youtube channel for 3d game tutorial in Java
im on 18:31
I made setObject() far better.
basically it takes in the name of the object to be set, whether or not it takes collisions, and it's tileX and tileY (i have a function to calculate position in pixel via tileX/Y), then, the function gets the correct image for that object, then places it in the right position. very cool, huh?
you should call it ObjectKey or ObjKey instead of "OBJ_Key"
Why?
public void PlaceWorldObject() {
//add objects
gp.object[0] = new object_key();
gp.object[0].worldX = 4 * gp.tileSize; //worldX cannot be resolved???
gp.object[0].worldY = 25 * gp.tileSize; //worldY cannot be resolved??
both ints are public in the object class though & object class is public, with no errors instantiating in the gp, any idea where I went wrong?
UPDATE: was my bad, I should know better Object is already defined in Java.lang so i changed class to WorldObject and works!
I really enjoy your tutorial so far. I am wondering wouldn't it be better to make GameObject abstract, sicne we are repeating some code in Key and Door class.
So we could for example have:
package nl.xx1.horsebird.object;
import lombok.Getter;
import lombok.Setter;
import nl.xx1.horsebird.GamePanel;
import javax.imageio.ImageIO;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.util.Objects;
import static nl.xx1.horsebird.GamePanel.TILE_SIZE;
@Getter
@Setter
public abstract class GameObject {
private BufferedImage image;
private String name;
private boolean collision;
private int worldX;
private int worldY;
public abstract String getName();
public GameObject() {
try {
BufferedImage image = ImageIO.read(Objects.requireNonNull(getClass().getResourceAsStream(String.format("/objects/%s.png", getName()))));
setImage(image);
} catch (IOException e) {
throw new RuntimeException(e);
}
}
public void draw(Graphics2D g2d) {
int screenX = worldX - GamePanel.localPlayer.getWorldX() + GamePanel.localPlayer.getScreenX();
int screenY = worldY - GamePanel.localPlayer.getWorldY() + GamePanel.localPlayer.getScreenY();
g2d.drawImage(image, screenX, screenY, TILE_SIZE, TILE_SIZE, null);
}
}
And then we could have a class:
package nl.xx1.horsebird.object;
import javax.imageio.ImageIO;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.util.Objects;
public class Key extends GameObject{
@Override
public String getName() {
return "key";
}
}
I think we could also improve the code a bit to make some things static in GamePanel so we don't have to pass GamePanel down the road all the time. Let me know what you think about it. Anyway great series!
hello, these are great tutorials thank you so much.
The error indicates that your code is failing to read the image at line 44 in the TileManager. That's where you want to check.
@@RyiSnow thank you so much for answering, i found the error, it was an old version of a water tile which i wasn't using and it was saved as .gif and not .png.
It's my first time coding in java and i started 4 days ago thanks to you