Continuing documenting functions

git-svn-id: svn://svn.code.sf.net/p/magicseteditor/code/trunk@575 0fc631ac-6414-0410-93d0-97cfa31319b6

doc/function/set_alpha.txt

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+Function: set_alpha
+
+--Usage--
+> set_alpha(image: image, alpha: transparency value)
+
+Make an image more transparent.
+
+The transprarency is multiplied by @alpha@.
+If @alpha@ is 1 the image stays the same, if @alpha@ is 0 the image becomes completely transprent.
+
+--Parameters--
+! Parameter	Type			Description
+| @image@	[[type:image]]		Image to make transparent.
+| @alpha@	[[type:double]]		Transparency factor.
+
+--Examples--
+> set_alpha(image: "image1.png", alpha: 0.5)  ==  [[Image]]
+>>> set_mask(image: <img src="image1.png" alt='"image1.png"' style="border:1px solid black;vertical-align:middle;margin:1px;" />, alpha: 0.5) == <img src="image_set_alpha.png" alt='"image_set_alpha.png"' style="border:1px solid black;vertical-align:middle;margin:1px;" />
+
+--See also--
+| [[fun:set_mask]]		Set the transparancy mask of an image.