3D item animations

[Thornack]

I have been playing around with items and have figured out how to render 3D items when thrown and held and dropped. I wish to now give the item some animations and I was wondering how to call animations in minecraft. I tried looking at it and it doesn't seem simple. I have figured out how to give a mob basic animations that I guess get called when the AI decides to call them but I want to understand how they work better.

 

I understand that there are several parameters you can change to make techne models look good: scaling (how large your model will be), rotation (might be required if the Techne model you made was backwards), and height (your model might be partially underground or floating, which needs to be fixed).

 

I understand that all transformations in Minecraft are done using the OpenGL functions: glRotatef, glScalef, and glTranslatef. These functions operate on an internal transformation matrix which combines all previously applied transformations into a single 4x4 matrix, which is then used during rendering. One quirk of OpenGL is that all operations applied will appear in REVERSE order! Usually this will not affect your transformations, but in some special cases it might.

For mobs when doing the transformations, your code should go in the mobs model.java file, in the render function before everything else. Also, in order to use OpenGL, you must add the import to the top of the file :

import org.lwjgl.opengl.GL11;

 

1) Scaling

Scaling is done using the glScalef function.

GL11.glScalef(x, y, z);

The x, y, and z parameters determine how much in each direction the model should be scaled, with 1.0 meaning no change. If you only want to scale the model, x, y, and z should all be the same.

 

2) Rotation

Rotation is done using the glRotatef function.

GL11.glRotatef (angle, x, y, z);

The angle determines how much to rotate the model, in degrees. The x, y, and z parameters make up a 3D vector which determines the axis to rotate around (not sure if it needs to be a unit vector).  Typically to keep it simple, you will only want to rotate around either the x, y or z axes at once, and simply make multiple calls to glRotate if you want to rotate around multiple axes.

For example, the following code will rotate the model by 180 degrees around the y-axis, so it will face backwards:

GL11.glRotatef(180.0f, 0.0f, 1.0f, 0.0f);

In this case, the rotation axis is the y-axis, which is (0,1,0).

 

3) Height

Vertical and horizontal translation is done using the glTranslatef function.

GL11.glTranslatef ( x, y, z);

The  x, y, and z parameters simply determine how far to move the model.

Note: The translate function actually moves the ‘world’, NOT the model. This means that you will need to apply the opposite for it to go where you want. For example,

GL11.glTranslatef(0.0f, -0.5f, 0.0f);

Will move the model up by 0.5 units.

 

 

Example render function:

  public void render(Entity entity, float f, float f1, float f2, float f3, float f4, float f5)

  {

//OpenGL transformation code. Remember that all transformations are applied in the

//opposite order that they are called in

GL11.glTranslatef(0.0f, -0.5f, 0.0f); //move model up a little bit

GL11.glRotatef(10.0f, 1.0f, 0.0f, 0.0f); //pitch 10 degrees downwards

GL11.glRotatef(180.0f, 0.0f, 1.0f, 0.0f); //rotate so the model is no longer backwards

GL11.glScalef(5.5f, 5.5f, 5.5f); //scale the model 5.5x  

 

setRotationAngles(f, f1, f2, f3, f4, f5);

Face.render(f5);

Bottom_Chin.render(f5);

head_L.render(f5);

head_R.render(f5);

head.render(f5);

  }

 

What i do not understand is how to call animations so that they can be implemented by being called in methods such as the on right click or on impact methods that are available for items. Any help would be appreciated.

 

[Jdb100]

Make A Boolean and when the item is used set it true then add in the render to do a certain thing if that Boolean is true

[Thornack]

could you provide me with an example

[darty11]

In your entity file:

public YourEntity(World w)
{
//yourcode
this.getDataWatcher().addObject(25, defaultintvalue);
}

public void setYourVariable1(int I)
{
this.getDataWatcher().udateObject(25, I);
}

public int getYourVariable1()
{
this.getDataWatcher().getWatchableObjectInt(25);
}

//whenever you want to change your variable:
{
this.setYourVariable1(newval);
}

In your model file:

  public void render(Entity entity, float f, float f1, float f2, float f3, float f4, float f5)
  {
if((entity insanceof YourEntity)&&((YourEntity)entity).getYourVariable1==valueneededtoanimate)
{
   //OpenGL transformation code. Remember that all transformations are applied in the
   //opposite order that they are called in
   GL11.glTranslatef(0.0f, -0.5f, 0.0f);      //move model up a little bit   
   GL11.glRotatef(10.0f, 1.0f, 0.0f, 0.0f);   //pitch 10 degrees downwards
   GL11.glRotatef(180.0f, 0.0f, 1.0f, 0.0f);   //rotate so the model is no longer backwards
   GL11.glScalef(5.5f, 5.5f, 5.5f);      //scale the model 5.5x    
}     
   setRotationAngles(f, f1, f2, f3, f4, f5);
   Face.render(f5);
   Bottom_Chin.render(f5);
   head_L.render(f5);
   head_R.render(f5);
   head.render(f5);      
  }