====== Part 14 – FX ======

Every game needs an objective. In our game, the hero needs to the top of the platforms to reach the flashing star.

We don't have a star asset, so I've provided one below:

<WRAP center round box 60%>
{{ :guides:beginners:star.png?nolink |}}
</WRAP>



Right and click this image and save it as "star.png" in the ''data/texture'' folder in our project.

Create a object section for this star and position it at the top right hand platform:

<code=ini>
[StarGraphic]
Texture = star.png

[StarObject]
Graphic  = StarGraphic
Position = (290, -260, 0)
</code>

Add the star to the Scene section's child list so that it is created when the platforms are:

<code=ini [highlight_lines_extra="4"]>
[Scene]
ChildList = PlatformObject # MiddlePlatformObject #
TopLeftPlatformObject # TopPlatformObject # TopRightPlatformObject #
StarObject
</code>

(Don't forget the ''#'' on the line above ''StarObject'').

Run the game and you will have a star in the top right hand corner:

{{:guides:beginners:beginners-33-star-positioned.png?nolink|}}

It will be nice if the star pulses colour and slowly turns. We can use two FXSlot sections for this:

<code=ini>
[StarFlashSlotFX]
Type		= color
Curve		= sine
StartTime	= 0
EndTime		= 1
Absolute	= true
StartValue	= (255,0,0)
EndValue	= (255,255,0)

[StarRotateSlotFX]
Type       = rotation
Curve      = linear
StartTime  = 0
EndTime    = 2
StartValue = 0
EndValue   = 359
</code>

Now group the two slots under one FX section:

<code=ini>
[StarFX]
SlotList    = StarFlashSlotFX # StarRotateSlotFX
KeepInCache = true
Loop        = true
</code>

The FX section will be in charge of ensuring they stay in memory and that they both loop.

Add the FX to the StarObject:

<code=ini [highlight_lines_extra="4"]>
[StarObject]
Graphic  = StarGraphic
Position = (290, -260, 0)
FXList   = StarFX
</code>

Cool. Run that and the star should turn and flash.

The only problem is that the turning pivot for the star is a little off. Fix that on the StarGraphic:

<code=ini [highlight_lines_extra="3"]>
[StarGraphic]
Texture = star.png
Pivot   = center
</code>

Run that. And it will turn nicely.

One more tweak, a minor detail: As the sprite is turning, there are some jaggies. Smooth them out my applying ''Smoothing'' to the ''StarObject'':

<code=ini [highlight_lines_extra="6"]>
[StarObject]
Graphic   = StarGraphic
Position  = (290, -260, 0)
FXList    = StarFX
Pivot     = center
Smoothing = true
</code>

Run that and you should get:

{{:guides:beginners:beginners-34-star-fx.png?nolink|}}

Great! Next, is to make the hero collide with the star in order to win the game.

The star object will need a static body, with a solid body part:

<code=ini>
[StarBody]
Dynamic   = false
PartList = StarBodyPart

[StarBodyPart]
Type        = box
Solid       = true
SelfFlags   = star
CheckMask   = hero
</code>

And add the body to the ''StarObject'':

<code=ini [highlight_lines_extra="6"]>
[StarObject]
Graphic   = StarGraphic
Position  = (290, -260, 0)
FXList    = StarFX
Smoothing = true
Body      = StarBody
</code>

We've also declared flags to make sure that we only care if the star collides with the hero and nothing else.

We will set that collision up in a moment.

----

Next: [[en:guides:beginners:collision_events|Part 15 – Collision Events.]]

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