Java & LibGDX: Limit Rendering Range of a Sprite

Question

Recently I switched from using an array of integers as my screen in Java to using a library. The library I'm using is LibGDX, and the conversion for me is quite different. Most things I have already started to get the hang of, and I'm still writing a bit of the code myself.

At this point, I'm curious if I can limit the rendering range of Sprites and any other factor of drawing, such as if a sprite stuck half-way out of a box, it wouldn't render the part that was sticking out (as so:)

Is there a way to render in a specific range, and if it is partially out of the range, it doesn't render what is out of the range, or will I have to do that myself?

Answer 1

You can do simple "clipping" to a rectangle with the LibGDX ScissorStack.

Because OpenGL is stateful and many of the LibGDX drawing APIs cache, be sure to "flush" or "end" your batches within the range of the scissors. See libgdx ScissorStack not working as expected and libgdx Cutting an image

Answer 2

If i did not missunderstand you, you are looking for camera.
The camera lets you define a Viewport (size) and you only see things inside this Viewport.
You can also move it arroung to see other parts of the world.

For example:

OrthographicCamera cam = new OrthographicCamera(80, 45);

This defines a camera, which showes you 80 units in x and 45 units in y. It P(0/0) by default is in the middle of the screen, so this camera shows objects from -40 to +40 in x and -22.5 to + 22.5 in y.
You can move it, so that the P(0/0) is in the left lower corner:

camera.position.x = -40;
camera.position.y = -22.5;
camera.update();

This should move the camera to the left by 40 units and down by 22.5 units, so that the P(0/0) is the left lower corner. Don't forget to call update() as this recalculates the projection and view matrix.

Finally, to draw with this camera, you need to set the SptieBatchs projectionMatrix to the one of the camera:

spriteBatch.setProjectionMatrix(camera.combined);

Now you can use this SpriteBatch to draw.
You should also consider to se ViewFrustum-Culling, which means, that you don't draw things out of the camera, because they will never appear on screen, but the draw call costs some performance.