To start our game we first start to design (or perhaps find on the Internet) the graphics that we'll be using for the game. To start with our needs are very simple, we just need a few sprites to get us started. Many sprites and tilesets can be found on the internet. Firstly we'll need a stone block, then we'll need a stone tile so we can build our first level. Then we'll need something to collect. Lastly and most importantly we'll need a character to move around the level. Right click and select 'save image as' for each of them if you want to use these sprites in your game:
Once you have these sprites to hand, fire up Game Maker and have a look around. At first the interface can seem quite daunting, there are a ton of options. Thankfully it doesn't take long to get used to the interface. If ever you get stuck and need some help with Game Maker, press F1 to bring up the Help file (which in itself is quite extensive).
In the left hand side bar right click on the 'sprites' folder and select 'add sprite' from the menu which will bring up the add sprite screen. You will then be able to click on the 'Load sprite' button to select one of the sprites you created (or found) earlier. At the moment we are going to use a grid of sprites that are all 32x32 pixels in size. So our room is going to be composed of tiles that size. Ideally your character should also be 32x32. The one I'm using here is a bit taller than 32pixels tall, which is why I've selected the origin of the character to start 17 pixels down, and also manually set the bounding box to be within a 32x32 square. It might help you to start with it you settle for a character that is 32x32 then you can go with the default settings.
Notice that the 'Transparent' box is ticked. This feature of Game Maker takes the color from the bottom left (or was it right? I can never remember...) corner of the sprite and uses that as a transparent color. In this case, everything in bright neon green will become transparent. Notice we ticked, precise collision checking; this is processor intensive but that won't matter for this small game. In more elaborate games, it's best to untick this box wherever you can get away with it (when unticked Game Maker just uses the bounding box to check for collisions, more on collisions later). Finally we have 'smooth edges' ticked,which will blur the edges making the sprite look better in the room and 'Preload texture' ticked ensuring that the sprite will be loaded before it is needed. If you use a 32x32pixel character for now then the origin will be x:0 and y:0 while bounding box can be left at automatic. Otherwise the bounding box will have to be within a 32x32 pixel square or else your character will get stuck in walls. Notice that we called the sprite 'sp_character'. The prefix is used so that we can tell the difference between different game elements. You'll find out why soon. Press the 'Ok' button to continue.
Now add the other sprites. The block has different settings from the character sprite. It's still transparent because it doesn't fill the 32x32pixel area (although if you do have a block that fills the whole square then be sure to untick 'transparent') but in this case we have unticked precise collision checking since there are going to be a lot of these sprites, and we don't need precision anyway since the bounding box is a close enough approximation of the block's shape. Note that we called it 'sp_block'. As with before it is also preloaded.
We repeat the same process by adding the gem. Again we don't need precise collision checking, because the character is only going to be bumping against it and picking it up. (advanced collision checking is more useful in games such as shoot-em-ups where you only want to die if you really are touched by the object).
At this juncture it's probably a good idea to save your game if you haven't already done so. Go to the file menu and select 'save as' then give your game an appropriate name. This means if anything happens you can reload.
So now we should have a character a block and a gem in our sprites section. Now it's time to add the floor tile. Three folders down from the sprites folder is the 'backgrounds' folder. Right click on this and the 'Background Properties' window will pop up. Load your floor tile into this as if it was a sprite and call it 'bg_tile'. Note that the prefix is different because it's a background. This naming convention is not needed by game maker, but comes in handy to keep things organized. The background properties allows you to load in background images and tile sets. Tile sets are an extremely powerful way of managing game graphics. All the sprites you need (to build the room) can be loaded into one sheet, and then loaded into game maker and used to create the level by layering them into a design. For now we'll have to be content with one floor tile for the background.
