Just make sure you have a texture saved in that folder as moonTutorial.png or your code will error. You can copy any of the planet textures from Galacticraft, or make your own.
setBodyIcon is the icon used to draw the moon on the Celestial Screen, it is a 48 pixel by 48 pixel png located in forge/src/main/resources/assets/tutorialMoon/textures/gui/celestial. The setTier is used to define what tier rocket you need to access the planet. The next three set methods called are used to draw the object on the Celestial Screen, play around with them until they look right. We are setting it's parent to be the overworld: in essence this is a second moon for the overworld. The string passed to the constructor is the unlocalized name of your moon, you need it for your lang files. tDimensionInfo(3, TutorialWorldProvider.class) Breaking it down, the first part is simply declaring a new object. tRelativeOrbitTime(100F).setTierRequired(1).setBodyIcon(new ResourceLocation(this.ASSETPREFIX, "textures/gui/celestial/moonTutorial.png")) MoonTutorial = (Moon) new Moon("Tutorial").setParentPlanet(GalacticraftCore.overworld).setRelativeSize(0.0017F).setRelativeDistanceFromCenter(new CelestialBody.ScalableDistance(8F, 8F)) The first is defining the moon object, seen here: Now if you have any experience with Forge modding, most of this should look familiar. What I am going to do is show you all the code then explain bits and pieces of it. Like any mod, you want to create your file first. With setup out of the way, lets move on to the hard part: the code. (Thanks to Radfast for telling me how to do this) After that command is run, you should be able to launch Galacticraft from your IDE. This time the command is gradlew clean setupDecompWorkspace -refreshDependencies.
Put both of those files in /src/main/resources, then you need to run gradle again. The next two files you need to grab are access transformers, they will tell forge to make certain minecraft methods visible. Boot up your IDE and add those three jars to the java build path. Anyways, with the legal stuff out of the way, you then want to drop those three jars into a new folder in your forge directory titled libs. To be clear, I do NOT own these files, I just did this as a convenience for myself and am sharing it with you. Those files are distributed under the same license that the main mod files are, the LGPL. You will want to grab the UNOFFICIAL jar files from my jenkins, located here. Once you have that done, you need to grab some files. You then want to follow the install directions, accessible here. It would be best if you also used that version when making your addon. The first thing you need to do is download forge source from here. But with Forge's switch to Gradle, it has gotten a little tricky. Like any forge mod, the first step is to set up your development environment. You have a little bit of experience with Forge modding, or you are at least comfortable googling what you do not know.You have an IDE installed, such as Eclipse (recommended) or Netbeans.I wont answer questions when the answer is "Go learn Java" Disclaimer aside, lets get to some modding! I will do my best to keep this tutorial up-to-date until a stable API is released. However, the 1.7 API is still changing on a constant basis. Luckily for any prospective addon makers, Mic and Radfast have done an excellent job in making the 1.7 API extremely easy to use. A lot has changed since my last one, and this is going to be my attempt to explain it.
Back with another tutorial on making an addon for Galacticraft 1.7.