View source for Add character to scene

In this tutorial we will add a female alien character to the scene. We will let her walk by the cell once in a while.<br>
If you try to talk with her, she gets angry and says you should be quiet.

[[file:alien_abduc1.jpg|600px]]

==Steps==
<ol>
<li>Copy the files from the '[[Tutorial resource pack]]' for this tutorial to the appropriate directories.<br>
We will describe these files here briefly:<br>
* <code>/init/story/alien</code>: This is the brain for the alien character. Just like the player each character has a brain.
* <code>/scenes/capture</code>: These are the motion capture files used for the alien character.
* <code>/scenes/character6</code>: These are the character and cloth meshes.
* <code>/scenes/charobj</code>: These meshes are used for collision detection for characters in general.
* <code>/scenes/sounds</code>: These files are the sound files used for the character.
* <code>/scene/textures</code>: These files are the texture files used for the character.
</li>
<li>Now we need a location that is the starting point for this character.<br>
Open the spaceship scene <code>scene.ma</code> and create a duplicate instance of the waypoint object.<br>
A duplicate instance copies only the instance of the object not the mesh itself. Name the copy <code>waypoint2</code> and place it outside the cell like this:<br>
[[file:maya_waypoint1.jpg|600px]]
</li>
<li>Open the <code>/init/story/alien/init.dat</code> file.<br>
In the pose settings you see that the <code>scene_id = SPACESHIP1</code> and <code>waypoint = "waypoint2"</code>.<br>
The pose contains all pose settings for this character. The character is derived from the object <code>CHAR_BASE</code>, you can find more pose settings in the file:<br>
<code>/init/std/base/char/char_base.dat</code>. You see that the scene_id and waypoint are overridden.</li>
<li>Start the adbucted scene and if all went well, you should see an alien character outside your cell.</li>
<li>Now lets make her look at you and change her expression. Open the <code>/init/story/alien/brain/dyn.dat</code> file. This file contains the dynamic state for the brain.<br>
Here you can add brain state variables that can be changed during the game. They are automatically saved when you save the game.<br>
The variables <code>main_focus_type</code> and <code>main_def_exp</code> do not only contain a value but can also be used to set the actual focus and expression.<br>
Set <code>main_focus_type = STARE</code> and <code>main_def_exp = A_BIT_ANGRY</code>. This will make the character stare and you with an somewhat angry expression.<br>
Run XStoryPlayer and you should see that she follows you with an somewhat angry expression.</li>
<li>Now we want the alien character to keep walking around in the spaceship. Add two more waypoints to the scene like this:<br>
[[file:maya_waypoint1.jpg|600px]]<br>
Name them waypoint3 and waypoint4. Set the starting waypoint in the pose settings of the alien to waypoint3.<br>
Now start XStoryPlayer again. Press F6 to go into free view mode. "Fly" around the wall and you should see the alien behind it now.
</li>
<li>Now we will add some walking scripting. Walk planning is automatically calculated based on the the collision objects in the scene.<br>
In debug mode a file called <code>coll.tga</code> is created in the home directory of XStoryPlayer. It contains the path information.<br>
So we only have to redirect the character using the script and she walks by herself.<br>
Open the <code>/init/story/alien/brain/run.dat</code> file. It contains the code that is run for each brain.<br>
Replace the code with this:
<syntaxhighlight lang="cpp">
#include "init/std/base/char/brain/code/run.dat"

//-------------------------------------------

<*state_run>

res = true;

case (state.dyn.me.do.state)
{
  [RUN0] state_run0();
}

</state_run>


//-------------------------------------------


<state_run0>

case (state.dyn.me.do.state2)
{
  [NONE]
  {
    // Set timer to 20 seconds
    do_set_timer(20);
    
    state.dyn.me.do.state2 = START;
  }
  
  [START]
  {
    // Wait for timer
    loc.ts = GetTs();  
    [loc.ts < state.dyn.me.do.ts] return;
		
    state.dyn.me.do.state2 = WALK1;
  }
  
  [WALK1]
  {
    // If busy with pose then wait
    [state.dyn.me.pose.result == NONE] return;

    // Walk towards waypoint4 and stand there
    // No need to end exactly on this waypoint	
    loc.state.pose_type = STAND;
    loc.state.waypoint  = "waypoint4";
    loc.state.exact     = 0;
    SetPose(loc.state);
		
    state.dyn.me.do.state2 = WALK2;
  }
  
  [WALK2]
  {
    // If busy with pose then wait
    [state.dyn.me.pose.result == NONE] return;
		
    // Walk towards waypoint3 and stand there
    // No need to end exactly on this waypoint	
    loc.state.pose_type = STAND;
    loc.state.waypoint  = "waypoint3";
    loc.state.exact     = 0;
    SetPose(loc.state);
		
    state.dyn.me.do.state2 = WALK1;
  }
}

</state_run0>
</syntaxhighlight>
This code will make the character walk between the two waypoints continuously.<br>
Start XStoryPlayer and after the player has gotten the feedback "Wait, I believe I hear someone coming...", you should see the alien girl walking by.
</li>
<li>Now give some feedback when you see the girl. Add this code to the player run.dat file:
<syntaxhighlight lang="cpp">
[START3]
{
 [state.dyn.me.avatar.id == ALIEN &
  state.dyn.me.avatar.range <= 6]
 {
   feedback.s = "An alien girl?? Why is she looking so angry...";
     
   state.dyn.me.do.state2 = SEEN_ALIEN;
 }
}
</syntaxhighlight>
Now after you see the alien girl you get this feedback.
</li>
<li>We want the alien girl to say something when you talk to her. The ref.dat file for the alien character can be used for this.
Open it and change the <code>ref.state.run0</code> code to this:
<syntaxhighlight lang="cpp">
run0
{
  hello.greet =      
  {
    talk.s = "Be quiet prisoner!";
  }

  get.get   = hello.greet;
  if.get    = hello.greet;
  when.get  = hello.greet;
  where.get = hello.greet;
  why.get   = hello.greet;
  set.get   = hello.greet;
  info.get  = hello.greet;
  word.get  = hello.greet;
}
</syntaxhighlight>
When the character is in the RUN0 state it will receive talk events. We can use the <code>ref.state.run0</code> code variables to react on these talk events.<br>
Using the above code we basically react to any talk event and let the alien reply that you should be quiet.<br>
Start the story and say something to the alien when she walks by. She should respond like programmed.
</li>
<li>Now we want her to come to you when you talk to her. Before we can do that first edit the collider objects a bit.<br>
We want the girl not to collide with the outer cell colliders only the player. Change the scene.ini file likt this:
<syntaxhighlight lang="cpp">
rb "collShape1"
{
  physics
  {
    elem[0] {mesh = "collShape1";}
    elem[1] {mesh = "collShape2";}
    elem[2] {mesh = "collShape3"; coll_type = NONE; coll = MASK_VIEWER;}
    elem[3] {mesh = "collShape4"; coll_type = NONE; coll = MASK_VIEWER;}
  }
}
</syntaxhighlight>
Rerun the filemaker. <code>coll_type = NONE</code> ensures the collider is not used in the path planner for the character.<br>
<code>coll = VIEWER</code> ensures the character does not collide with the collider only the player.
</li>
<li>
Now change the character <code>ref.state.run0</code> code to this:
<syntaxhighlight lang="cpp">
run0
{
  hello.greet =      
  {
    // Run to cell when you talk to her
    loc.state.pose_type = STAND;
    loc.state.waypoint  = "waypoint2";
    loc.state.speed     = 2;
    loc.state.exact     = 0;
    SetPose(loc.state);

    // Store old state
    state.dyn.me.do.prev_state = state.dyn.me.do.state2;
        
    state.dyn.me.do.state2 = WALK_CELL;
  }

  get.get   = hello.greet;
  if.get    = hello.greet;
  when.get  = hello.greet;
  where.get = hello.greet;
  why.get   = hello.greet;
  set.get   = hello.greet;
  info.get  = hello.greet;
  word.get  = hello.greet;
}
</syntaxhighlight>
Also edit the alien character <code>run.dat</code> file and add:<br>
<syntaxhighlight lang="cpp">
[WALK_CELL]
{
  [state.dyn.me.pose.result == NONE] return;

  talk.s = "Be quiet human!";
        
  // Proceed with old state
  state.dyn.me.do.state2 = state.dyn.me.do.prev_state;
}
</syntaxhighlight>
So when you talk to her she goes into the WALK_CELL state and when she arrives at your cell she says "Be quiet human".<br>
After that she proceeds with her route.<br>
Test the newly added scripts now.</li>
<li></li>
</ol>