I an currently using Libgdx Animation class( com.badlogic.gdx.graphics.g2d.Animation) in a game. However I need the animation to grow in size on certain events. How do I accomplish this?
Animation is used to select the correct frame (TextureRegion) based on the time elapsed. It has nothing to do with how you render that frame. Therefor it is not different as how you render anything else.
You didn't provide enough information for that. But usually you'd render it something like this:
TextureRegion textureRegion = animation.getKeyFrame(time += delta);
spritebatch.draw(textureRegion, x, y, width, height);
So to change the size would be to change the width and height variables. You didn't provide enough information on how you'd like to do that. But you can do that for example using this:
width = 0.8f;
height = 1.9f;
Related
I've some problem for render Box2D Debug with Box2DDebugRenderer.
I've 2 OrthographicCamera, one for render the world (named Cam) and one for the HUD (healthBar, Armor, ...) (named hudCam).
I've tried to render :
b2dr.render(world, cam.combined); -> I can't see the Box2D
b2dr.render(world, cam.projection);
b2dr.render(world, hudCam.combined);
b2dr.render(world, hudCam.projection);
b2dr.render(world, new OrthographicCamera().combined); and b2dr.render(world, new OrthographicCamera().projection)
I can't find a way to render the Box2D exactly like cam, to see the edge of all bodies.
If somebody understand my problem, please help me !
Thx.
Unfortunately some tutorial out there suggest to use a meter-to-pixel-conversion when using Box2D. This is not neccessary (at least with Libgdx), as this conversion can be done by using a camera.
The problem in your case is, that you are using a meter-to-pixel-conversion when rendering the Sprites, while the Box2DDebugRenderer renders everything 1:1.
To solve this problem you have to get rid of the meter-to-pixel conversion and use the camera or the viewport to "scale" the things.
THis way, the Box2DDebugRenderer and your SpriteBatch can (and should) use the same camera to render.
For the camera/viewport:
The constructor has the params width and height. Those params are often set as Gdx.graphics.getWidth() and Gdx.graphics.getHeight(), which in my optinion is not right, the game should be resolution-independent.
You should instead select those values depending on how big your player (or any other visible entity) is in real life and how big it should be on screen.
Let's say you have a little characte, like in your game. It is 1m tall in real live and should take 1/13 of the screen height (more or less like in your first picture, where the screen is about 13 times as high as the character).
So your cameras height should be 13, your characters height (also it's Box2Ds Body height) should be 1m. Next you need to define the width. For that i like to think about my desired aspect ratio. Lets assume the game should focus on 16/9 devices, the width is then (13/9)*16=23.
Now your camera should be created like this:
camera = new OrthographicCamera(23, 13);
Basically my problem is simple - I have a ParticleEffect which looks nice on small screen but on my private phone (Samsung S4) it looks very small. My question is: How can I scale the effect?
I have already done something like this:
// Callback method
public void addEffect(Vector2 position, boolean special) {
// Callback Method for the particle effects
PooledEffect effect;
if (!special)
effect = (MathUtils.random(0, 1) == 0) ? yellow_star_pool.obtain()
: green_star_pool.obtain();
else
effect = special_star_pool.obtain();
effect.setPosition(position.x, position.y);
effect.scaleEffect(Values.Scalar_Width*1.3f);
effects.add(effect);
}
But the result is that the effect is scaling exponentially, something I don't want.
I just want the effect to be scaled so that it will look the same on all screens. How can I achieve that?
First, I want to explain why current approach doesn't work. Note that the method you use for scaling is named scaleEffect, not setScale. Every time you call it the effect will be scaled relative to its current state. When you use pooled particle effects you scale the effect as many times as the particle had been reused. That's why you see it scaling exponentially.
So, the solution is to scale only the particle effect that you use as a prototype for the pool. Something like:
prototypeEffect.scaleEffect(Values.Scalar_Width * 1.3f);
ParticleEffectPool yellow_star_pool = new ParticleEffectPool(prototypeEffect, 10, 100);
Then you didn't have to scale every particle effect you obtain.
I've included a zoom functionality similar to the one explained at this website:
http://www.flashandmath.com/howtos/zoom/
This works perfectly on my background image(a map, that is), but I want to keep the symbols on my map the same size while zooming in.
I probably could work this out by changing all the children's size when calling the zoom-function, but I am hoping there is some kind of easy code adapt in my children class to make the size of the instances unchangable. Is there?
Thanks!
One crude way, so you don't have to calculate the symbols scale, would be to remove the symbols from the mapDisplayObject so they're no longer a child and instead put symbol placeholders. Then match each symbol's x and y to each place holder, using localToGlobal...
If your children are not scaled or skewed or rotated you can iterate all of them and set transformation matrix to 1/parentScale. Something like:
for each (var child:DisplayObject in parent) {
var matrix:Matrix = child.transform.matrix;
matrix.a = 1/parentScale;
matrix.d = 1/parentScale;
child.transform.matrix = marix;
}
I'm brand new to AS3, trying to take a bitmap from the library and display it in the timeline with actionscript. Here's the code I'm using so far as per Adobe's site:
addChild(new Bitmap(new myBitmap(100, 100)));
and this works, but changing the dimensions in those brackets doesn't. How can I change the dimensions?
Also, how can I change the position of the bitmap? Right now it's at 0,0.
You first get a handler of that bitmap:
var theBitmap:Bitmap=new myBitmap();
Then, you can change its coordinates:
theBitmap.x=100;
theBitmap.y=100;
addChild(theBitmap);
In order to do scaling, you can also alter its scaleX and scaleY properties as with any other displayed object. In order to make a Bitmap object to be of certain size on screen, you have to scale it so that scaling parameter equals (new dimensions)/(old dimensions). But, if you want something else, you have to explain it further.
So I am super stoked to start using LibGDX for my first android title for OUYA and PC, but I am running into some snags with LibGDX. (All of my questions can be answered by looking at source, but I am really trying to understand the design choices as well).
To start with, the coordinate system. I created a project using the Project Setup jar, and it creates an OrthographicCamera like so
camera = new OrthographicCamera(1, h/w);
From my reading, I understand that LibGdx uses bottom left corner for 0,0 and yUp. Fine.
I see that it is pretty easy to change to y down if I want to, but I am not understanding the next bit of code that was created.
For the default sprite that gets created the position is set like so.
logoSprite.setOrigin(logoSprite.getWidth()/2, logoSprite.getHeight()/2);
logoSprite.setPosition(-logoSprite.getWidth()/2, -logoSprite.getHeight()/2);
When I run this basic program, I see the logo image I have added is centered on the screen. What I am trying to understand is why the values are negative in set position, and why is it using the sprite width and height instead of the graphics w and h of the view port? If I change to the screen width and height, then the image is drawn in some odd position in the lower right hand side of the screen.
My next question is sprite.setSize vs sprite.setScale. Why is the difference between the two? (They appear to do the same thing, except setScale leaves getWidth and getHeight unchanged).
Since my game will be using a 2D camera heavily for panning, zooming and rotation, I am trying to understand as much as I can about the libgdx framework before I start writing any code.
As a side note, I have a game development and math background and I have made several 2D and 3D games using XNA. I am finding LibGdx a bit frustrating as it does not abstract away OpenGL as much as I was expecting it to, and so far the 2D drawing I have been experimenting with seems to be more confusing than it should be!
I also wanted to note that I am planning to use spine for my animations. Should that change my choice to use y-up or y-down?
If you want to draw a sprite in center of screen, do this in your create method
logosprite.setposition(scrw/2-logosprite.getwidth()/2,scrh/2-logosprite.getheight/2);
here scrw is your viewport's width,
and scrh is your viewport's height,
this way your sprite will be in center of screen
sprite.setsize is used for setting size of the sprite and sprite.setscale is used when we scale a large/small texture so that its quality remains good in all devices(hdpi.mdpi,xhdpi,ldpi)..
no need to worry if you are using spine it works smoothly in libgdx..
You can use just this code if possible
logoSprite.setPosition(Gdx.graphics.getWidth()/2 - image.getWidth()/2,
Gdx.graphics.getHeight()/2 - image.getHeight()/2);
To center the sprite into the middle of the screen Where "image" is the Texture you have loaded/declared initially.
As for why it is coming in a odd position is due to the fact that you are using a camera.
Which changes the view a lot just go through the documentations of libgdx about camera here
In my case, I needed to set position of camera and then call update() method.
Then never forget camera's (0,0) is its center. Everything is being placed that way. My camera code:
private void cameralariUpdateEt() {
cameraGame.position.set(cameraGame.viewportWidth * 0.5f,
cameraGame.viewportHeight * 0.5f, 0);
cameraGame.update();
cameraScore.position.set(cameraScore.viewportWidth * 0.5f,
cameraScore.viewportHeight * 0.5f, 0);
cameraScore.update();
}
Call this method from inside render();
Step 1: Set the sprite origin to the position you would like it to rotate around.
// camera center point is (c.x, c.y)
logoSprite.setOrigin(c.x, c.y);
Step 2: make sure to set your sprite center to origin
logoSprite.setOriginCenter();
Step 3: Rotate your sprite
logoSprite.setRotation(Angle);
Step 4: Set the sprite position, [subtract half the sprites width and height to center the sprite]
logoSprite.setPosition(c.x - logoSprite.getWidth() / 2, c.y - logoSprite.getHeight() / 2)