Some questions Ive been needing to ask

Hello! I began trying to program on JMonkey some time ago. Ive been coding java for about one year…

I am 22, english is NOT my native language, but I will do my best to write a understandable english.



1 - When developing the game, should I save all the assets in a big ZIP file?

2 - What exactly is the .j3o format? And why should I use them instead of raw ogre files?

3 - Scenes

3.1 - In the town.zip example, the texture files are included. Can I create scenes by using external textures?

3.2 - Should all scene be saved in a zip file?

3.3 - Is it better to use scenes? Or I can simply make terrains (https://wiki.jmonkeyengine.org/legacy/doku.php/jme3:beginner:hello_terrain) and populate them by myself?



I really enjoyed the JMonkey engine, so a big thanks for any response :slight_smile:

  1. keep the assets in the Assets directory that is provided when you create a new project in the SDK. You can keep all files there and exclude the source files in the build script so your users do not end up with them


  2. j3o is JME’s format. It is easily and quickly read/written by JME and is by far the most desired format to use for performance. If you used ogre files, then each time you loaded a model it would have to convert from ogre, to j3o. Might as well skip that first, slow, step.



    3.1) Models have materials, and each material can have different and separate textures.

    3.2) it should be saved as a .j3o file. You can create a new scene in the SDK right-click → new → other → scene → empty jme3 scene

    3.3) a scene ends up being just a node (spatial), so you can import a scene into your game and also add terrain to it. Or you can create terrain in the editor and save that as a scene. You can combine it however you want and whatever works best for your requirements.
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  1. No, the SDK will package it efficiently for each platform https://wiki.jmonkeyengine.org/legacy/doku.php/sdk:application_deployment
  2. Because its the internal format and can save all options as opposed to the generic formats https://wiki.jmonkeyengine.org/legacy/doku.php/jme3:intermediate:multi-media_asset_pipeline
  3. You can use models from editors given they are created in a compatible way. The town example is not a very good example as it uses single textures and hence causes a lot of objects https://wiki.jmonkeyengine.org/legacy/doku.php/jme3:external:blender

    3.1) Huh? You can create heightmaps from images and import models with textures that you edited in a 3d editor. And combine both plus particle effects etc. in the scene composer

    3.2) See 1)

    3.3) You will always have a scene, I don’t exactly what you mean by that. A terrain with some models on it is a scene. The interior of a house, entirely created from models and parts would also be a scene.
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Thanks for the answers, they really clarified things for me. :slight_smile:

Just a small question, I’m implementing the physics from the last tutorial, but it seems the ball is created inside the Player, and that causes unwanted directions for the ball…

How would I create the ball at the player’s location + a little bit towards the cam’s direction?



ball_geo.setLocalTranslation(player.getPhysicsLocation());



It creates the ball inside the player, I need to translate it a bit further from the player, in the cam’s direction.

I tried multiplying the vectors, and some other things, but could’nt find out a solution :confused:

And thanks again :slight_smile:

https://wiki.jmonkeyengine.org/legacy/doku.php/jme3:math_for_dummies