LibGdX - modifying Sprites and Animating them

Engines, Libraries and Tools
#1

Hey guys I’m having trouble with running proper animations on my game.
I used texture packer to put all the animations of my ninjaboy character.

the images are saved as idle_001, idle_002 etc etc.

My problem is that when I apply changes to the sprite for example setScale(0.3f, 0.3f) it only works if I render this specific sprite, but when i render it through an animation the changes don’t take effect.

Here is my code


package com.haki.loh.entities;

import com.badlogic.gdx.Gdx;
import com.badlogic.gdx.graphics.Texture;
import com.badlogic.gdx.graphics.g2d.Animation;
import com.badlogic.gdx.graphics.g2d.Sprite;
import com.badlogic.gdx.graphics.g2d.TextureAtlas;
import com.badlogic.gdx.math.Vector2;
import com.badlogic.gdx.physics.box2d.BodyDef;
import com.badlogic.gdx.physics.box2d.BodyDef.BodyType;
import com.badlogic.gdx.physics.box2d.FixtureDef;
import com.badlogic.gdx.physics.box2d.PolygonShape;
import com.badlogic.gdx.utils.Array;
import com.haki.loh.gametates.GameState;

public class Player extends Entity {
	private TextureAtlas textureAtlas;
	private Array<Sprite> ninjaBoyIdle;
	private float time;
	private Animation animation;

	public Player(GameState state) {
		super(state);
		this.batch = state.getBatch();
		
		//load texture pack file
		textureAtlas = new TextureAtlas(
				Gdx.files.internal("images/ninjaboy/ninjaboy.txt"));
		
		//create Array of Sprties
		ninjaBoyIdle = textureAtlas.createSprites("idle_");
		
		//resize all sprites
		for (int i = 0; i < ninjaBoyIdle.size; i++) {
			ninjaBoyIdle.get(i).setScale(0.3f, 0.3f);
		}
		
		//create the animation
		animation = new Animation(1 / 12f, ninjaBoyIdle);

		world = state.getWorld();
		BodyDef bdef = new BodyDef();
		bdef.position.set(160 / PPM, 200 / PPM);
		bdef.type = BodyType.DynamicBody;
		body = world.createBody(bdef);
		PolygonShape shape = new PolygonShape();
		shape.setAsBox(14 / PPM, 14 / PPM);
		FixtureDef fdef = new FixtureDef();
		fdef.shape = shape;
		body.createFixture(fdef).setUserData(body);

		// create foot
		shape.setAsBox(4 / PPM, 4 / PPM, new Vector2(0, -14 / PPM), 0);
		bdef.position.set(160 / PPM, 100 / PPM);
		fdef.shape = shape;
		fdef.isSensor = true;
		body.createFixture(fdef);

	}

	@Override
	public void update(float dt) {

	}

	@Override
	public void render() {
		batch.begin();
		batch.draw(animation.getKeyFrame(time += 1 / 60f, true), 0, 0);
		batch.end();
	}

}

From the code above the animation is playing and everything is working except that I changed the scale of everything inside the SpriteArray before i loaded it into the Animation class. The changes did not take effect…

However if I change the render() to this


public void render() {
		batch.begin();
		ninjaBoyIdle.get(i).draw(batch);
		batch.end();
	}

The changes I made on the for loop will apply. If anybody could provide guidance it would be much appreciated.

#2

I don’t understand why batch.draw() don’t respect some sprite changes.

You can use this for now.

batch.draw(animation.getKeyFrame(time += 1 / 60f, true), 0, 0, someWidth, someHeight);

I think you can’t use setWidth ou setHeight on Sprite, only setRegionWidth and setRegionHeight. So you can use bounds(x, y, w, h).

float ninjaScale = 0.3f;

		for (int i = 0; i < ninjaBoyIdle.size; i++) {
	         ninjaBoyIdle.get(i).setBounds(
	        		 0,
	        		 0,
	        		 ninjaBoyIdle.get(i).getWidth()*ninjaScale,
	        		 ninjaBoyIdle.get(i).getHeight()*ninjaScale);
	      }
#3

hey Thanks I guess that can work but I also need to flip stuff. I might just not use the animation class or the batch.draw(). Anyway I’ll google a bit more.

#4

jsut an update sprite.setFlip(boolean x, boolean y); does work on the same for loop as the code above. I’ve tried setRotation() and setScale() and setAlpha() none of which seemed to work with batch.draw()

EDIT: Just did some further testing setRotation() setScale() and setAlpha() does work if i draw it like this.

ninjaBoyIdle.get(0).draw(batch);

but for batch.draw() only flip seems to work for me.

#5

Folks over at LibGdx said that it is expected behavior as Sprite extends TextureRegion. So the correct way of drawing is sprite.draw();

#6

Correct, from what I understand the SpriteBatch draw methods are only called when you want to draw just a texture. If you are working with the Sprite class, or any other class that has a draw method, you shouldn’t handle the drawing yourself.

#7

Yes, this make sense.

It’s funny because I just @Override some draw() methods from actors and totally forgot about this. :persecutioncomplex: