Hello everyone, I'm interested in making a simple tile based 2d platformer in the style of ghouls n ghosts. But i'm having trouble finding information on how to begin. I've found tutorials on youtube that use c++ but nothing using plain c. I know I could probably adapt the info from one of these c++ tutorials into c, but they all tend to go straight into classes and inheritance and all the garbage of c++ that i'm not interested in.

Does anybody know of a tutorial or guide that could at least point me in the right direction? I know enough allegro and c to make simple shmups that constantly scroll, with parallax backgrounds and animations but I have no idea how to set up a tile based map, make tiles solid etc...

Cheers!

Try yourself

*This is a basic example, from memory*

All you have to do is adjust camera_x and camera_y. You can adjust by pixel amount or whole tile size;

What I do is put player in the middle. If the player crosses an imaginary boundary then adjust the camera to counter movement;

example: The map above is for a 640x480 grid. You can put boundary at 80 and 560;

if (player_x < 80)
{
    camera_x -= (80 = player_x);
    if (camera_x < 0) camera_x = 0; // keep in check
    player_x = 80;
}

if (player_x >= 560)
{
    camera_x += (player_x - 560);
    if (camera_x >= (MAP_WIDTH - (GRID_WIDTH * CELL_WIDTH))) camera_x = (MAP_WIDTH - (GRID_WIDTH * CELL_WIDTH)));
    player_x = 559;
}

Thank you all for your replies, I think there's enough here to get started. I'm now realising I actually know less about game design than programming. It's just
the map that's moving.. damn. So, does the player just float a certain tile height? as in there's no coding of solid/ethereal for the ground? If the ground is two tiles deep then the player's y position (at feet) is window height - 2* tile height?

There are no tilemap classes in AllegroFlare yet for me to share, so my apologies on that.

Right now I have 7 different tile map projects, each implementation is different so there are a lot of approaches that can work depending on your needs. I'm in the process of consolidate them all into a single one, Tileo being the most consolidated one so far. It does lack a simple renderer like the one DanielH sketched out. I should probably add that next before anything else.

The more advanced renderer is a mesh renderer (the tiles in the tilemap are placed on a single 2 dimensional 3d mesh of squares, each square is a tile in the map).

One version also uses a custom ALLEGRO_PIXEL_FORMAT which includes normal data for each pixel, so dynamic lighting effects can be added via shaders. I have a couple screenshot of that:

{"name":"612202","src":"\/\/djungxnpq2nug.cloudfront.net\/image\/cache\/1\/a\/1a581cc2b8faecb4db7cb3c0646e0fec.png","w":894,"h":552,"tn":"\/\/djungxnpq2nug.cloudfront.net\/image\/cache\/1\/a\/1a581cc2b8faecb4db7cb3c0646e0fec"}
{"name":"612204","src":"\/\/djungxnpq2nug.cloudfront.net\/image\/cache\/7\/0\/70ca9136a765391ebb09477e56d5fa15.png","w":1052,"h":638,"tn":"\/\/djungxnpq2nug.cloudfront.net\/image\/cache\/7\/0\/70ca9136a765391ebb09477e56d5fa15"}
{"name":"612201","src":"\/\/djungxnpq2nug.cloudfront.net\/image\/cache\/5\/9\/5960af68c4b4aa46ead54c140ed4fe80.png","w":1037,"h":632,"tn":"\/\/djungxnpq2nug.cloudfront.net\/image\/cache\/5\/9\/5960af68c4b4aa46ead54c140ed4fe80"}
{"name":"612200","src":"\/\/djungxnpq2nug.cloudfront.net\/image\/cache\/8\/0\/80fe41b0ac13721b7648318c74a5dc6a.png","w":902,"h":615,"tn":"\/\/djungxnpq2nug.cloudfront.net\/image\/cache\/8\/0\/80fe41b0ac13721b7648318c74a5dc6a"}
{"name":"612198","src":"\/\/djungxnpq2nug.cloudfront.net\/image\/cache\/c\/9\/c9bc8901833a3e58c579d6623a6cc41f.png","w":1017,"h":510,"tn":"\/\/djungxnpq2nug.cloudfront.net\/image\/cache\/c\/9\/c9bc8901833a3e58c579d6623a6cc41f"}

Collision for tile maps is another topic.

I spent a couple hours and made this code as a simple example of what I was talking about.

I don't do plain c, so I tried my best not to overcomplicate it.

Any questions, just ask.

This is a simple horizonally scrolling tilemap. There are layers &background, solid, foreground, items, etc). At the moment there is only drawing layers and no collision checking. Only boundary checking. The "player" is the red rectangle. With the left and right keyboard buttons you can move left and right. The camera will scroll accordingly.

The tile bitmap is pretty empty at the moment, but enough for example.

You might have to adjust location of where to load the tiles.

This is a GREAT resource : http://www-cs-students.stanford.edu/~amitp/gameprog.html#tiles

I hope this is in a book someday

There is one thing that sometimes takes time to realize / re-invent, when you see how platform games work : Some tiles have to count as "soft" platforms.

A completely "solid" tile will resist player movement from every direction. As a result, the player always stays 'outside' of it:

1. Horizontally, you can not walk into it : if your feet, head or body would overlap, the horizontal movement is halted.

2. If you jump, your head is not allowed to enter it. The jump will be halted, and you will start falling instead.

3. It will "break your fall" if you're falling into its top edge. As long as your character's feet are resting on it, you don't fall.

"soft" platforms only apply ruler n°3). Most platform games have such. If the player has no jump-down controls that lets them fall through them voluntarily, the level design has to take it into account (there are holes or designated ladders, or no need to go back down).

Yes, but that's not "simple"

I'd just like to thank you all again for the info in this thread, I appreciate all the responses even if I haven't acknowledged everyone, I have absorbed your wisdom. This whole endeavour of game making has been overwhelming. Making games is damn hard. I've battled with so many collision detection and response problems over the last week. But I feel they've really strengthened my understanding of C.

Thanks everyone.