I thought it'd be kinda neat to show people what the insides of the engine look like on a typical day.
You can click on that thumbnail to see the full size. That's the frame editor. It's where we build the world, set up preferences and behaviors for objects, and modify animations. You'll notice the gigantic object list. Most of the objects are detectors: invisible blocks that have their positions set relative to actual game objects such as Link. They create flexibility so it's easier for us to see and program when Link should play a certain animation, or ignore player movement. On the right side of the editor you'll notice three little frames. These are layers, used to organize and order our objects. We put the inventory on the third layer, and simply use some events to switch the activity of layers. (The world is essentially deactivated, or paused, while the inventory layer is active)
This is the event editor. All those little checkboxes are events programmed into the game by us. A condition must occur before an event can happen. For example, you'll see 'Start of Frame' and then a few checkboxes positioning Link and the player mask. Those events will only occur at the very beginning of the frame (a frame is equivalent to a room in Game Maker). You might ask why some conditions are in red while others are in regular color. A red condition indicates a more important flag to check for in a loop. The way MMF works, the executable constantly loops through these conditions looking for events to activate. When it comes across a red condition, it is given more priority over additional conditions under it. This saves time in the looping process. In the picture, you can see that Condition 11's red one is a check for "On ForEach loop". MMF will entirely skip the routine check for this event if that ForEach loop is not activated. It won't even look at the condition under it, or the events associated with it. The result is that MMF loops faster, and events happen closer to realtime.
*MMF is a relatively simple software, and in some cases less complex than Game Maker. I would not recommend jumping straight from MMF to C, or using MMF as a foundation for learning a higher language. The software is simply logic-based. But for a hobbyist like me, this is my go-to for coding fan games when I have no interest in furthering my knowledge of real programming language.
