I think I might be about to ask a dummy question, but I'm still new with Android programming, and I couldn't (despite all my efforts) find my answer on Google.
The thing is, I'm trying to develop a little game, with 2D Graphics. I want my "gaming board" to be at a specific position on my screen, so that I can display in-game informations above and below the box. But since there is beginning to be a lot of Android phones out there, I was thinking about getting "dynamic" values so that I can adapt my font size to every device.
My game is not in full screen (but it could be, it's no big deal), but in a window with no title bar.
I'm using an extension of the default SurfaceView class, implementing SurfaceHolder.Callback. I tried writing the following method :
public void getViewSize()
{
VIEW_WIDTH = this.getWidth();
VIEW_HEIGHT = this.getHeight();
}
but the values returned are zeroes.
Anyone got an idea (even if it means changing display strategy) ?
Thanks a lot.
You can do this:
public void onDraw(Canvas canvas) {
VIEW_WIDTH = canvas.getWidth();
VIEW_HEIGHT = canvas.getHeight();
}
Related
Am trying to understand the following piece of code. According to the author,
he is trying to reset the camera position based on the gutter width and height. By gutter, I take it the author means the black bars on the screen.
The problem is that I cant seem to find the methods
setViewport(int,int,boolean) and getGutterWidth() and getGutterHeight() on the Stage class. I think this code was written with an outdated Libgdx API. What am looking for is the equivalent code that will perform the same task as this outdated code:
private Stage stage;
public void resize(int width, int height){
stage.setViewport(MyGame.WIDTH, MyGame.HEIGHT, true);
stage.getCamera().translate(-stage.getGutterWidth(),
-stage.getGutterHeight(), 0);}
These black bars are now handled by the viewport classes, see https://github.com/libgdx/libgdx/wiki/Viewports for a overview and short description.
In our case I would suggest a FitViewport:
Viewport viewport = FitViewport(MyGame.WIDTH, MyGame.HEIGHT, camera);
Stage stage = new Stage(viewport);
I need to draw line graph with lakes of points in canvas rendering. I used following ways to optimize the performance,
Avoided to create object in onDraw method.
Using drawLines method in canvas rather than using path.moveTo and path.lineTo, since, my thought is path is always render using CPU not GPU.
Removed line anti-alias.
Not set alpha value for line color.
Set HardwareAcceleration to true.
Using some sampling algorithms.
This is what i actually doing after read some performance tips to get good performance, If you know to make even better please suggest to me.
Instead of drawLine you can use drawRect. And use SurfaceView. (Quite honestly, I don't like SurfaceView for some limitations it has and organise back buffers myself, but most of developers prefer it).
This is what comes to my mind (without testing and thinking much).
Suppose you have a table grpData[] of float data, each in range 0f to 1f. You also have a table of colours (not colour resource Ids) grpColours.
Them your code will look smth like this:
private Paint p = new Paint();
#Override
public void onDraw(Canvas canvas) {
super.onDraw(canvas); // Draws background
int width = getWidth();
int height = getHeight();
int count = grpData.length;
float xStep = (float) width / count;
float x=0f;
for (int i=0; i<count, i++) {
float nextX = x+xStep;
p.setColor(grpColours[i]);
canvas.drawRect(x, (1f-grpData[i])*height, nextX, height, p);
x = nextX;
}
}
PS. I am not sure that hardware acceleration really helps. On the contrary it may cause problems with some cheap devices.
I'm trying to make my app detect when two bitmaps intersect each other. This is the code I tried for collision:
//width and height of the two bitmaps
int width1 = bplay1.getWidth();
int height1 = bplay1.getHeight();
int width2 = bbrick1.getWidth();
int height2 = bbrick1.getHeight();
if (height1 < height2)
if ( width1 < width2)
{
currentscore.setText("collision detected");
}
However, the app crashes on start when I use getHeight() and getWidth(). Am I doing something wrong with it?
If it crashes, what output does it generate in the crash (in logcat)?
Assuming it crashes with null pointer exception (which to me seems most likely based on the very terse information you provided), you should make sure your bplay1 and/or bbrick1 objects are not null like so: bplay1 = new MyClass();
Summary: Whenever you post a S.O. question ask yourself this: If I found this post, what information would I be likely to need to solve it? In this specific case there is actually very little to go on.
i'm trying out libgdx as an opengl wrapper , and i have some issues with its graphical rendering :
for some reason , all images (textures) on android device look a little blurred using libgdx . this also includes text (font) .
for text , i thought that it's because i use bitmap-fonts , but i can't find an alternative- i've found out that there is a library called "gdx-stb-truetype" , but i can't find how to download it and use it .
for normal images , even when i show the entire image without any scaling , i expect it to look as sharp as i see it on a computer's screen , especially if i have such a good screen on the device (it's galaxy nexus) .
i've tried to set the anti-aliasing off , by using the next code :
final AndroidApplicationConfiguration androidApplicationConfiguration=new AndroidApplicationConfiguration();
androidApplicationConfiguration.numSamples=0; //tried the value of 1 too.
...
i've also tried to set the scaling method to various methods , but with no luck. example:
texture.setFilter(TextureFilter.Nearest,TextureFilter.Nearest);
as a test , i've found a sharp image that is exactly the same as the seen resolution on the device (720x1184 for galaxy nexus , because of the buttons bar) , and i've put it to be on the background of the libgdx app . of course , i had to add extra blank space in order for the texute to be loaded , so the final size of the image (which will include content and empty space) is still a power of 2 for both width and height (1024x2048 in this case) .
on the desktop app , it look ok . on the device , it looked blurred.
a weird thing that i've noticed is that when i change the device's orientation (horizontal <=> vertical) , for the very short time before the rotating animation starts , i see both the image and the text very well .
surely libgdx can handle this , since the opengl part of the api-tests project of android shows images just fine.
can anyone please help me?
#user1130529 : i do use spritebatch . also , here's what i do for setting the viewport . it occurs whether i choose to keep the aspect ratio or not.
public static final int VIRTUAL_WIDTH =720;
public static final int VIRTUAL_HEIGHT =1280-96;
private static final float ASPECT_RATIO =(float)VIRTUAL_WIDTH/(float)VIRTUAL_HEIGHT;
...
#Override
public void resize(final int width,final int height)
{
// calculate new viewport
if(!KEEP_ASPECT_RATIO)
{
_viewport=new Rectangle(0,0,Gdx.app.getGraphics().getWidth(),Gdx.app.getGraphics().getHeight());
Gdx.app.log("DEBUG","size:"+_viewport);
return;
}
final float currentAspectRatio=(float)width/(float)height;
float scale=1f;
final Vector2 crop=new Vector2(0f,0f);
if(currentAspectRatio>ASPECT_RATIO)
{
scale=(float)height/(float)VIRTUAL_HEIGHT;
crop.x=(width-VIRTUAL_WIDTH*scale)/2f;
}
else if(currentAspectRatio<ASPECT_RATIO)
{
scale=(float)width/(float)VIRTUAL_WIDTH;
crop.y=(height-VIRTUAL_HEIGHT*scale)/2f;
}
else scale=(float)width/(float)VIRTUAL_WIDTH;
final float w=VIRTUAL_WIDTH*scale;
final float h=VIRTUAL_HEIGHT*scale;
_viewport=new Rectangle(crop.x,crop.y,w,h);
Gdx.app.log("DEBUG","viewport:"+_viewport+" originalSize:"+VIRTUAL_WIDTH+","+VIRTUAL_HEIGHT+" aspectRatio:"+ASPECT_RATIO+" currentAspectRatio:"+currentAspectRatio);
}
Try this:
TextureRegion.getTexture().setFilter(TextureFilter.Linear, TextureFilter.Linear);
Try the following:
texture.setFilter(TextureFilter.Nearest, TextureFilter.Nearest);
There are several types of TextureFilters. I assume that the Linear one (is that default?) is blurring.
If you have the Chainfire 3D application or another which reduce textures or change it to 16bit, turn it off; that works for me, and I had the same problem.
I know this has been asked before and I went through all the answers and nope this ain't that, and yes I have the activity named in the manifest so it's not that.
Here's my problem:
I have a sprite moving across the screen and when in the window where you choose the livewallpaper, I have a preference that lets the user choose the height (so they can move the sprite up or down) the only problem is the sprite is constantly moving so when they use the seekbar to move the sprite up or down I get the old 'Window already focused, ignoring focus gain of" Now if I go out and come back in again of course this stop and restarts it and the new preference hight is already in their so it moves to the new height then but not in the live preview.
Here is the sprite code:
private void addShipOne() {
int heightPosition = (screenSized / 2) - (screenSized / /*this.bigShipHeight*/gettheFreakingHeight());
int widthPosition = 0;
Point startPoint = new Point(widthPosition, heightPosition);
this._shipone.add(new SpaceShipOne(this._context, this, startPoint, 125));
(sorry about the method name I was using to test a quick version I was a bit frustrated at that point) lol
It then goes into an OnDraw method then into the render to render it all.
public void render(){
Canvas canvas = null;
try{
canvas = this._surfaceHolder.lockCanvas(null);
synchronized (this._surfaceHolder) {
this.onDraw(canvas);
}
}finally{
if(canvas != null){
this._surfaceHolder.unlockCanvasAndPost(canvas);
}
}
}
I have another preference that allows the user to choose the frequency of the ships appearing it works fine but it goes from left to right and changes ships then so it updates the frequency then, but the height one doesn't work, I tested the log to make sure the height int goes through and it does so its not that, the only thing I can come up with is the maybe add this when the ship turns left or right, but it does not work while its moving by the looks of it.
this.bigShipHeight is where the new height value goes into ( I was just testing it another way with the gettheFreakingHeight() (I used an if else statement for that method that used the frquency preference instead which does work nicely.
Just to add the full code part.
In the onDraw(Canvas canvas)
I render the _shipone as such
for (Renderable renderable : this._shipone) {
renderable.render(canvas);
}
Any help would be appreciated.
Thanks in advance
Sam
Ok I should of looked into the my sprite class first, sorry about this I answered my own question once again and it was too obvious, that's what I get for looking at the code way to long, I should walk away then come back it always is clearer then.
Just in case others run into this issue I'll put the answer.
In my sprite class which SpaceShipOne runs from I just added this
this.getSprite().setYPos(this._blimp.gettheFreakingHeight());
This updates right away with no window already focused.
I don't know why I didn't see this last night because it is the only place it can be added and be updated right away, all I had to do was set the Y position to the preference instead.
It works like a charm.
Hope this helps someone else out
Sam