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Is there a way to draw Strings in libgdx without BitmapFonts?

I want to draw Strings in my Libgdx game but i cant use BitMap Fonts because the scale of my game is to smal to use them.

It sounds like you mean the scale of your viewport is too small to show fonts correctly. There are two solutions. The first is better for legibility while the second is quick and dirty.
One is to use a second viewport for the UI that has an appropriate scale for text. You would first call gameViewport.apply(), draw the game, and end the batch. Then use uiViewport.apply() and then draw the UI. The downside with this method would be if you want to draw text that aligns with moving objects in the game, you would have to use the two viewports to convert coordinates. Otherwise, this is the ideal method to get a crisp looking UI. Ideally you would use a ScreenViewport and select a font size at runtime based on the screen dimensions, either by shipping your game with multiple versions of the font at different scales, or by using FreeTypeFontGenerator.
The second method is to scale down all your text. First call bitmapFont.setUseIntegerPositions(false) do it won't round off positions to integers. Then call bitmapFont.setScale() with however much you want to shrink it to fit in your game viewport.

There is a gdx-freetype project:
https://www.badlogicgames.com/wordpress/?p=2300
and it uses TrueType fonts as source to generate bitmap font on the fly.
Not sure how stable this is - didn't use it.

Using world coordinates

I am currently using pixels as units for placing objects within my world, however this can get tedious because I only ever place objects every 16 pixels. For example, I would like to be able to place an object at position 2 and have the object rendered at the pixel position 32.
I was wondering if the best way to do this is simply having a pixel-to-unit variable and multiplying/dividing based on what I need to be doing with pixels or if there is a better way.

You shouldn't use constant a pixel-to-unit conversion, as this would lead to different behavior on different screen sizes/resolutions.
Also don't forget about different aspect ratios, you also need to take care about them.
The way you should solve this problem is using Viewports.
Some of them support virtual screen sizes, which are what you are looking for. You can calculate everything in your virtual space, and Libgdx converts those things to pixels for you.
They also take care about different aspect ratios in different ways.
The FitViewport for example shows black borders, if the aspect ratio is not the same as the virtual one.
The StretchViewport instead of showing black borders stretches the image to fit the screen.

Java 3D API - Prevent small texture blurriness

I have rendered this scene using the Java 3D API. At the bottom of the image, where the ground is closer to the viewer, there is a blurriness surrounding the black lines on the image. I would like to prevent this blurriness entirely. Here is the image I am using as the texture:
As you can see, it is quite small but making the image larger is not an option. Are there any scaling methods I can change the type of such as a "nearest-neighbour" option for Java 3D texturing?
Thanks!

As Banthar suggested, I used:
texture.setMagFilter(Texture.BASE_LEVEL_POINT‌​);
and it works perfectly with no blurriness.

Render string to texture in Android and OpenGL ES

I've googled around everywhere, but cannot find much for rendering strings to textures and then displaying that texture on a quad on the screen. Can someone provide a run-down on the process or provide good resources that describe how? Is rendering strings to textures even the best method for displaying text in an Android OpenGL ES app?
EDIT:
Okay, so LabelMaker interferes with alpha blending, the texture (created from a PNG with a transparent background) now has a solid black background, rather than a transparent background. If I comment out all the LabelMaker-related code, it works fine.
UPDATE:
Nevermind. I took a look at the code to find that LabelMaker was disabling blending after drawing the labels.

I think this is what you are looking for.

If you don't want to use GL extensions you need to create the font as a bitmap and then create a class to convert that string into quads that you can draw.
I use this method with the 2 fonts in my game. I have a class that takes a wide texture with all the letters evenly spaced, and a string that matches the image, then uses lookups on the letters to find out how far in the bitmap it should go.
Your other option is to render your text to a offscreen bitmap using android, and then bind the text as a texture. This will let you use androids built-in font processing and rendering to create texture-based fonts.
The second method I have not used yet, but I have rendered google maps to a offscreen canvas and then bound the bitmap as a GL texture, so doing it for text should be much simpler.
If you are planning to have modifying string data in a gl loop you need to really worry about StringBuilder too, because it causes GC and performance issues. I hardcode all my strings so it doesn't allocate, and all my rapidly numbers are done through a second draw function dedicated to drawing changing numbers without using string-builder.

What's the best way of reading a sprite sheet in Java?

I'm writing a basic sprite engine for my own amusement and to get better aquainted with Java's 2d API. Currently I am making use of large numbers of separate .png files with transparent backgrounds to represent the various sprites and different frames of animation that I need. Most 'real world' game development projects seem to make use of 'sprite sheets' which contain multiple sprites or frames of animation within a single file. Also, rather than making use of native image transparency support, people often nominate an arbitrary colour that does not appear in the sprite pallette to be the transparent colour. How does one manage a file like this programatically?
how do you know where one sprite
starts and the next begins
how do you deal with transparency
There may be other factors that I've not thought of here, so I may add to the list above as I think of things or as people make suggestions (please do so in the comments).

I currently use XML files generated by a simple sprite editor that store the sprite as a collection of (optionally animated) poses, which are in turn a collection of frames or cells. Frames store per-frame information like the x and y offset of the frame in sheet, cell width and height, and any transformation (resize/rotation/hue/etc.). Poses store individual frames and animation information (speed, for example), and a pose name to easily identify them in the program (hero.pose = sprite.pose["standing_right"]). Sprites serve as a document root to hold several poses, such as a pose for each facing direction.
A less flexible alternative I used earlier was to specify fixed sizes for cells and sheets and calculate frame offsets and sizes based on these values (e.g. width is always 32 pixels, so third sprite is at 32 * 2). Later I started specifying these dimensions in the file name (e.g. sprite_name_32x64.png) for sprites that don't fit the fixed cell dimensions. I like the new approach more, especially with a simplistic editor that fills most values for me and allows me to use sprites as templates for other sprites.
I use the alpha and transparency information stored in PNG images directly so I don't need to worry about storing it elsewhere, although other approaches would be to pick a fixed value per sprite and store somewhere, use the leftmost pixel in the pose if you know it's always empty, use a specific palette entry if you're using those, sprite masks, or what have you.

Not about java but generally you can make your all sprites in the same size. Thus, you will be able to generate your sprites in your game (or app) with a simple for loops.
But for different sized sprites there may be problem for spritesheet size (it can be larger than expected). So you must define an xml or json file for your spritesheet to find your sprite images in your code. You can use sprite sheet editors (there are plenty of them, I'm using Sprite Master) for quick and easy way to generate sprite sheet and coordinate datas.

Make your sprite sheet knowing the size and number of each sequence.
Grab a buffered image of your sheet and use something like this:
currentframe=spritesheet.getSubimage(x, y, w, h);
Your x and y will change based on the frame you are on. Keep the width and height the same to make things easy on yourself.
Forget trying to keep the entire game on one sheet. It's nuts and hard to manage. Use a new png for each animation sequence. If you are anal about saving space only create moving right animations and just flip the buffered image real time to move left.
Java will read png files with the alpha so don't worry about the transparency colour. Draw everything in pngs. Use Photoshop or Gimp.
Search google for java image TYPE_INT_ARGB

Well, since most of them are custom, those details are up to the implementor.
You'd generally have the file start with header information that contains the details of height/width and encoding, transparency, etc.
A lot of the time things are in one file because it is very expensive to open/read multiple files compared to open/read one file. Many game engines use zip or "ziplike" files with 0 compression to treat a single file as a filesystem.