The PDF file goes over all this with pictures, but the .lib file adds these Actions to Game Maker:
Change Visibility: This action changes whether the object is visible or not. A "non-visible" object does not perform the Draw Event.
Change Solidity: This action changes if the object is solid or not.
Change Depth: This action allows you to change the depth at which the object is drawn. Remember, a negative depth is drawn in front of objects with a positive depth.
Change Persistence: This Action changes whether or not the object is Persistent. Remember, a persistent object will appear in every room after it appears unless it is destroyed.
Change Object Mask: The object's mask is what influences its Collision Events. Select a sprite to use as the mask.
Test Alpha Value: The alpha value of an object is its transparency. A value of 1 means completely visible, a value of 0 means invisible. (This is NOT the same as making the object "non-visible"!) Anything between 0-1 makes the object semi-transparent. This Action works like the Test Variable Action, but the variable refers to the object's alpha.
Set Alpha Value: This Action allows you to set or change the alpha value of the object.
Scale the sprite: This Action is similar to the Transform Sprite Action, without the ability to change the sprite's angle. This is important, because "image_angle" is a Pro function. So now, you can scale your sprite without having to get Pro, OR learn the necessary GML. An object's default scale is "1". A scale factor of "2" doubles its size. And a scale factor of "0.5" will halve its size. Of course, these are only examples, the sprite can be scaled to any reasonable number. Also, the use of negative numbers can mirror the sprite.
Draw Variable Health: This action draws a healthbar to the value of a defined variable other than that, it works just like the normal Draw Health action. It must be placed in the Draw Event to function.
Draw own sprite, Lite: When an object uses that Draw Event, it no longer draws its own sprite. To remedy this, use this Action, which will redraw the objects sprite, whatever it is. If you have Game Maker 7 Pro, don't use this action, use the one below.
Draw own sprite, Pro: This Action functions the exact same as the Lite version, only it is more precise because it takes into consideration colour blending, scaling, rotation and alpha value.
Change textbox settings: This action allows you to change the Textbox's background, its button, alpha value, and its x/y position on screen.
Change Textbox text: Change the settings in the Textbox's text.
Change Textbox button text: Change the settings in the Textbox's button text.
Test distance to object: This Action functions like the Test Variable Action, but the variable refers to the distance to a different object from this object.
Test distance to point: Like the above action, but this tests the difference from the object performing the action to a (x/y) coordinate.
Test distance between points: Also like the first action, only now you can test the difference between one (x/y) coordinate and a second (x/y) coordinate. This can be used to test the distance between two objects as well by using "object0.x"/"object0.y" and "object1.x"/"object1.y".
Test obstruction: This function tests if there is a specific object between points (x1,y1) and (x2,y2). The final option is to use precise or non-precise collision checking, in order for this to be possible, precise collision checking must be enabled on the object's sprite. Note that this tests if there is SOMETHING between the two points. If you want to test if there is NOTHING between the two points, check the "Not" option.
This function can be used for an enemy to test if it can "see" the main character of the game, and if it does it can start shooting.
Test Sprite: This is a handy test action if you only want an object to perform a certain action if it has a certain sprite. It can save you the trouble of using variables to check if an object is, for example, shooting or not.
Test Room: This action, (like the one above) is useful when checking if the object is currently in a certain room or not. For example, you could have an object that displays different messages depending on which room it is in.
Align objects: This Action makes use of a code I wrote that will align the image_single of an object to those around it, sort of like an automatic tiling system. You will need to design your platform components based on the template that can be found in the Auto_alignExample.gmk that is included in the same folder as this document.
Object is the name of the object that this object is aligning with, this is usually the same object. Width refers to the width of the sprite in pixels, and Height refers to the height of the sprite in pixels.
The Bluish-Green Productions Logo: It's just my logo. It does nothing, but it sure looks nice doesn't it?