I am making a mod for Minecraft based off of Garden Warfare, and I need some wil with some stuff.

I could use some help with the following:

 

1. Changing player model via GUI

 

2. Have it be so depending on your player model depends on who is an enemy and ally (Who attacks you and who doesn't)

 

3. Change player health count depending on character model

 

4. New addition to the HUD: adding character ammo (or melee attacks)

 

5. Having to spend in-game currency to unlock new player models

 

I know this is a lot, but I just want my mod to be fairly complex.  If anyone can help, I would much appreciate it.  Thanks in advance.

First you should get antiquated with Capabilities.

http://mcforge.readthedocs.io/en/latest/datastorage/capabilities/

http://www.planetminecraft.com/blog/forge-tutorial-capability-system/

This will let you save extra data to the player. Then you will need to get used to OpenGL(if you are not already). This is the main rendering engine for Minecraft.

You will need to use RenderPlayerEvent.Pre to override the Players model and render it yourself.

The next thing is getting used to GUIs in Minecraft. They are pretty simple in nature. Create an extension of GuiScreen or GuiContainer(if it has Slots for Items). Note Gui#drawTexturedModelRect limits the full texture size to 256x256. Now to edit the players max health you need to use SharedMonsterAttributes.

EntityPlayer#getEntityAttribute(SharedMonsterAttributes...).applyModifier(new AttributeModifier(...));

Okay, thanks.  I'll try that.