Ccw: Created page with "{{Useful Function}} NOTOC This function returns a screen relative rotation to a world position. The returned rotation can be used in dxDrawImage ==Syntax== ..."

2014-02-13T08:07:26Z

Created page with "{{Useful Function}} __NOTOC__ This function returns a screen relative rotation to a world position. The returned rotation can be used in dxDrawImage ==Syntax== <syntaxhighlight lang="lua">..."

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{{Useful Function}}
__NOTOC__
This function returns a screen relative rotation to a world position. The returned rotation can be used in [[dxDrawImage]]

==Syntax==
<syntaxhighlight lang="lua">float getScreenRotationFromWorldPosition( float targetX, float targetY, float targetZ )</syntaxhighlight>

===Required Arguments===
* '''targetX''': The target world X position
* '''targetY''': The target world Y position
* '''targetZ''': The target world Z position

==Code==
<section name="Clientside script" class="client" show="true">
<syntaxhighlight lang="lua">
function getScreenRotationFromWorldPosition( targetX, targetY, targetZ )
-- Get camera position and rotation
local camX, camY, _, lookAtX, lookAtY = getCameraMatrix()
local camRotZ = math.atan2 ( ( lookAtX - camX ), ( lookAtY - camY ) )

-- Calc direction to
local dirX = targetX - camX
local dirY = targetY - camY

-- Calc rotation to
local dirRotZ = math.atan2(dirX,dirY)

-- Calc relative rotation to
local relRotZ = dirRotZ - camRotZ

-- Return rotation in degrees
return math.deg(relRotZ)
end
</syntaxhighlight>
</section>

==Example==
This example draws an arrow which points to the centre of the map.
<syntaxhighlight lang="lua">
addEventHandler('onClientRender', root,
function ()
local rotation = getScreenRotationFromWorldPosition( 0, 0, 0 )
dxDrawImage( 100,100, 100,100, "arrow.png", rotation )
end
)
</syntaxhighlight>

==See Also==
{{Useful_Functions}}

GetScreenRotationFromWorldPosition - Revision history

Ccw: Created page with "{{Useful Function}} __NOTOC__ This function returns a screen relative rotation to a world position. The returned rotation can be used in dxDrawImage ==Syntax== ..."

Ccw: Created page with "{{Useful Function}} NOTOC This function returns a screen relative rotation to a world position. The returned rotation can be used in dxDrawImage ==Syntax== ..."