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<h1>EntityX# ( entity[,global] )</h1>
<h1>Parameters</h1>
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<td>
entity = handle of Loaded or Created Entity
<br />
global = True for Global coordinates,  False for Local. Optional, defaults to False.
</td>
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<h1>Description</h1>
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<td>
The X-coordinate of the entity.

<br />
If the global flag is set to False then the parent's local coordinate system is used.

<br />

<br />
NOTE: If the entity has no parent then local and global coordinates are the same.

<br />
In this case you can think of the 3d world as the parent.

<br />

<br />
Global coordinates refer to the 3d world. Blitz 3D uses a left-handed system:

<br />

<br />
X+ is to the right

<br />
Y+ is up

<br />
Z+ is forward ( into the screen )

<br />

<br />
Every entity also has its own Local coordinate system.

<br />

<br />
The global system never changes. 

<br />
But the local system is carried along as an entity moves and turns.

<br />

<br />
This same concept is used in the entity movement commands:

<br />

<br />
MoveEntity entity, 0,0,1

<br />

<br />
No matter what the orientation this moves one unit forward.
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<h1><a href=../3d_examples/EntityX.bb>Example</a></h1>
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<td>
; EntityX / EntityY / EntityZ example.
<br />

<br />
; Escape quits, other keys move or pause the display.
<br />

<br />
Const width = 640, height = 480
<br />
Const KEY_ESC = 1, KEY_LEFT = 203, KEY_RIGHT = 205 
<br />

<br />
Graphics3D 640, 480
<br />
AmbientLight 50, 50, 50
<br />

<br />
Global isMoving = False     ; used to pause/resume movement 
<br />
Global count                ; how many updates have been done
<br />

<br />

<br />
; Set up a camera, light and three entities...
<br />

<br />
cam = CreateCamera()
<br />
PositionEntity cam, 0, 2, -50
<br />
CameraZoom cam, 4
<br />

<br />
lt = CreateLight() : TurnEntity lt, 30, 40, 0
<br />

<br />

<br />
Global oSphere, pCone, cSphere
<br />

<br />
oSphere = CreateSphere()
<br />
EntityColor oSphere, 250, 50, 0        ; Orange = Origin, parent of cone
<br />

<br />
pCone = CreateCone( 8, True, oSphere)  ;  will be a parent of small sphere
<br />
ScaleEntity pCone, .8, 2.0, .8
<br />
PositionEntity pCone, 8, 0, 0
<br />
EntityColor pCone, 255, 255, 0
<br />

<br />
cSphere = CreateSphere( 8, pCone )         ; child of the cone
<br />
EntityColor cSphere, 150, 150, 0
<br />
ScaleEntity cSphere, .4/.8, .4/2.0, .4/.8  ; try commenting out this line
<br />
PositionEntity cSphere, 0, 2, 0            ; above parent
<br />

<br />
; ... and we are ready run.
<br />

<br />
While Not KeyDown( KEY_ESC )
<br />

<br />
UpdateEverything	
<br />
RenderWorld
<br />
ShowInfo
<br />

<br />
Flip
<br />

<br />
Wend
<br />

<br />
End
<br />

<br />

<br />

<br />
Function UpdateEverything( )
<br />

<br />
; Nothing moves relative to its parent, so local coordinates are constant.
<br />
; Try uncommenting the PositionEntity command to change this.
<br />

<br />

<br />
If GetKey() Then isMoving = Not isMoving
<br />

<br />
If isMoving
<br />
TurnEntity oSphere, 0, .5, 0
<br />
TurnEntity pCone,  .2,  0, 0		
<br />

<br />
count = count + 1
<br />
a# = count Mod 360
<br />
;	PositionEntity cSphere, 0, 2 + Sin( a ), 0 ; experiment with this 
<br />

<br />
End If 
<br />

<br />
End Function
<br />

<br />
Function ShowInfo( )   ; global and local coordinates for all entities
<br />
Local x$, y$, z$
<br />

<br />
Color 255, 255, 255
<br />
Text 185, 20, "Global"
<br />
Text 495, 20, "Local"
<br />

<br />
Color 250, 50, 0 
<br />
Text  20, 50, "oSphere: " + XYZ( oSphere, True )
<br />
Text 400, 50, XYZ( oSphere, False )
<br />

<br />
Color 255, 255, 0 
<br />
Text  20, 75, "  pCone: " + XYZ( pCone, True )
<br />
Text 400, 75, XYZ( pCone, False )
<br />

<br />
Color 150, 150, 0 
<br />
Text  20, 100, "cSphere: " + XYZ( cSphere, True )
<br />
Text 400, 100, XYZ( cSphere, False )
<br />

<br />
End Function
<br />

<br />
; ******************************************************************
<br />

<br />
; These two functions just format the text display.
<br />
; Without them there are too many numbers crowding the screen.
<br />

<br />
Function Round#( x#, m# )		; returns x rounded to multiple of m
<br />
If m < 0.0 Then m = -m
<br />
s# = Sgn( x )
<br />
If x < 0.0 Then x = -x
<br />
diff# = x Mod m
<br />
If diff < .5 * m 
<br />
Return ( x - diff ) * s
<br />
Else
<br />
Return ( m + x - diff ) * s
<br />
End If
<br />
End Function
<br />

<br />

<br />
Function XYZ$( entity, globalFlag )
<br />

<br />
ex# = Round( EntityX( entity, globalFlag ), .001 )
<br />
ey# = Round( EntityY( entity, globalFlag ), .001 )
<br />
ez# = Round( EntityZ( entity, globalFlag ), .001 )
<br />

<br />
Return RSet( ex, 8 ) + RSet( ey, 8 ) + RSet( ez, 8 )
<br />

<br />
End Function
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<a target=_top href=../index.htm>Index</a><br>
<br>
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