Month: May 2016

Choosing the right resolution for a 2D Platformer

In this post I’ll try to write down the thinking process I made when I chose to develop Kren at a 384×216 sceen resolution.

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Tiles

Everything starts with the tiles. If you make tiles your measurement unit, you’re going to be able to simplify the visualization process. I made this kind of reasoning: how many 16px square tiles do I want displayed vertically?

Can you count the tiles? (hint: it's 15x10)
Can you count the tiles? (hint: it’s 15×10)

I wanted to be able to show at least 10 tiles. Which then I realized was a pretty low number for a Desktop game. That meant having a vertical resolution of 160px. That was the resolution of Metroid Zero Mission, on a Game Boy Advance. Granted, it looked great even on an emulator, on a Desktop PC… but… did I really want to go with that little number of tiles? Let’s look at how others approached the problem…

This is what the player sees on the monitor. Notice the small character and the whole room is in the view.
This is what the player sees on the monitor in Axiom Verge. Notice the small character. Also the whole room is in the view.

Axiom Verge, a more modern desktop platformer, is displaying almost 17 tiles vertically, at a vertical resolution of 270px. So I had to stop and ponder a little. Was it enough? Was it too much?

Too much indeed. Axiom Verge displays gigantic environments around one of the smallest player character I’ve ever seen. The player’s height to screen height ratio is absurd. But it works, for that game.

I wanted to keep a more claustrophobic feeling. Given I didn’t want to mess with tile size, I had to display less tiles. Simply by reducing the resolution.

Aspect Ratio

Metroid Zero Mission has a resolution of 240×160. It’s a 3:2 aspect ratio and it’s not what most computers use today (or even back in the days). In fact the 16:9 aspect ratio is now almost a universal standard. Or at least you can find it in most of the TV sets, desktops and notebooks you see around.

Back to Axiom Verge. It’s 16:9, which is great. But I already chose not to go with a resolution as high as 480×270 because I want less tiles on the screen.

Don’t get me wrong. If you want to be able to display a great number of 16×16 tiles on the screen, 480×270 is a really great option. I would advise you go with that resolution! It’s 1/16th the pixel area of a Full HD monitor. Which means it scales pretty well without pixel interpolation artifacts (you multiply 480 and 270 by 4 and you get the 1920×1080 Full HD resolution).

Next, I looked at the closest 16:9 resolution available with almost the same vertical resolution as the Game Boy Advance: 288×162.

I made a few tests at this resolution and even though I liked it (a lot), it doesn’t scale well. There’s no easy way to scale the 288×162 resolution to perfectly fit a 1920×1080 monitor. That means problems. Also, even though I liked the effect, it really is a little bit ugly. And maybe a little too much claustrophobic, even for my game; there’s barely enough space to fit 10 tiles, vertically. Given my player’s height is a bit more than 2 tiles, it meant huge player (yes, you can draw a different character), really small “field of view” and ugly pixels.

The 384 x 216 Compromise

I finally found the optimal compromise resolution: 384×216. Multiply that by 5 and you get the Full HD resolution. This should avoid pixel interpolation distortions. It also allows me to display 13.5 tiles vertically. This is not that far from the Game Boy Advance look, but it sits nicely between Metroid Zero Mission and Axiom Verge.

Testing the resolution and the view size. Notice the size of the Player and the smaller visible area.
What the hell is this?! (just a fun way to test player size, resolutions and ratios). It gave me familiar elements to gauge my observations.

I don’t want the player to feel small, inside gigantic environments. I want the players to feel the environment around them. Leaving him/her with little air. But not as little as in Metroid ZM on the GBA. All with a modern 16:9 look.

I found my own resolution with this process and a bit of testing. It might not be the best approach (in fact I’m sure I might have missed some other considerations) but for now it’s working great. Your mileage may vary so I recommend a lot of testing.

Kren Devlog #2 – Officially looking for a (Pixel) Artist

Today I started posting around forums. I’m looking for an artist. I have no artistic skills whatsoever; I cannot draw tilesets, sprites, animations… let alone concept art.

Become a Patron

My primary objective would be to prototype the game with graphics.

I still don’t know if this is going to be a commercial project or not.
Should it become a viable commercial game there could be many options. Here are just some of them

  • Prototype’s used to get funding. Then…
    • The artist remains the same, becoming the final game artist. Gets what is due to him/her, plus revenues shares.
    • The artist changes; prototype art won’t be used; he/she will get no revenues shares but will get what is due to him/her.
  • Prototype’s not a prototype anymore and is ready to market; no more funding necessary. Artist remains the same so revenue share model apply.
  • Project gets cancelled. No one gets anything (this should not happen! at all costs!) Artist is free to use his/her art however he/she sees fit.
  • Project is released as freeware (unlikely). Same as above.

The project is going for the commercial route. It’s now a revenue share work relationship.

Right now I’m unable to test the mechanics, to think about what works and what doesn’t; to imagine the game world. I need to quickly place things in the levels, test them and get an emotional response as to what works and what doesn’t.

That statement is a dramatic exaggeration. But you get the idea.

As of now, everything you see in the image below, except the blocks tilesets, were drawn by me. Ideally, this should change.

Still in early planning stages. Yet testing the platformer engine made in GameMaker.
Still in early planning stages. Yet testing the platformer engine made in GameMaker.

Right now I’m working full-time on this project.

Notes:

  • I will be trying to help the artist as much as I’m able to, given my limited artistic skills.
  • The game will have a resolution of 384 x 216.
  • Player will be more or less 36px tall.
  • The current game art won’t be used as a basis (thank god!)

Beware: the game videos/images are only there to show collisions and other tech aspect. The overall feeling of the game is going to differ drastically. Think Super Metroid (there, I said it).

This won’t be an action packed game.
In fact, when I think about it, I think about words like

  • solitude
  • isolation
  • mysterious
  • unearthly
  • uncanny
  • dark
  • ghostly
  • unnatural
  • dangerous

If you would like to collaborate, have comments or want to share your thoughts, leave a comment or get in touch via social networks etc.

EDIT:

Use the contact form I set up

Kren Devlog #1 – Upgrade System and Level Specific Items

Player now has data (like energy, starting_x and starting_y positions, starting direction and so on) and a nice inventory of permanent upgrades. I’ve called it inventory for the sake of it. It’s just an array (it really is) of stuff you can get through the whole game. Permanent stuff. Stuff you can get only once per whole game.

In every room (level) there are a number of different objects (like enemies and items). Most of these items will simply respawn once the Player gets back into the same room. Again and again.

This way it doesn’t matter how many times you killed the enemies in the room. As soon as you exit and re-enter the same room, all those enemies are just there. Again.

This is fine. Almost essential in some situation (believe me, there will be times when you’ll need more enemies to refill your energy or ammo levels).

The green stuff will not respawn once you pick it up. The enemy will, as soon as you re-enter the room.
The green stuff will not respawn once you pick it up. The enemy will, as soon as you re-enter the room.

So what’s with the level specific items? If you already acquired the high-jump ability, you won’t find it again in the level. This is where the inventory comes into play. And this is what I’ve coded today.

By the way I’m not using maps. I’m using simple arrays. I just defined a couple of macros so I can use my global array like it’s a key/value map. I get the added benefit of speed and code autocompletion in GameMaker. The only thing I made sure of, was to initialize the size of the whole array.

//Arrays
global.player[MAXARRAY]     = 0
global.inventory[MAXARRAY]  = 0

Obviously MAXARRAY is a macro (value is 255).

Then let’s say that I have another macro like PLAYER_DATA which is an expression referring to global.player. And I happen to have just the right macro for the 0th position of such array; ENERGY.

If I write PLAYER_DATA[ENERGY] = 99, it’d be like writing global.player[0] = 99. But now I have autocompletion in GameMaker and a list of defined, clear, meaningful, macros.

How I positioned the tileset in my tech demo

In the earlier tech demo, I had positioned a truckload of similar tilesets. Those bluish/greyish square blocks are not hand picked. I did not make that work in the level editor. I got inspired by the Smart Tile Objects tutorial by HeartBeast.

I simply downloaded the Square Blocks Textures from OpenGameArt.org, cut and pasted a bit in Paint.net to adapt it to my needs, and imported the end result as a background in GameMaker Studio.

My background version. Easier to import in GameMaker Studio.
My background version. Easier to import in GameMaker Studio.

I made so that when the floor/wall object (which is invisible) is created, it places random tile from that background into the level. Covering the same surface the object covers.

This makes for a pretty quick and dirty way to test a level with low object counts. Also gives me a little “randomized” effect every time I start the level.

What if I don’t want all that randomness? It’s as easy as using random_set_seed(1)

So, here is the create event of the smart object.

tile_fill_object(id, bg_blocks_16, 16, false)

And here is the tile_fill_object script

///tile_fill_obj(obj, tile, tile_size, randomize_tiles)

var obj         = argument[0]
var tile        = argument[1]
var tile_size   = argument[2]
var rand        = argument[3]

var col_num = background_get_width(tile) div tile_size
var row_num = background_get_height(tile) div tile_size

if !rand
{
    random_set_seed(1)
}

for (var row = 0; row < obj.image_yscale; row += 1)
{
    for (var col = 0; col < obj.image_xscale; col += 1)
    {
        var col_index = irandom(col_num - 1)
        var row_index = irandom(row_num - 1)

        tile_add(tile, col_index * tile_size, row_index * tile_size, tile_size, tile_size, obj.x + (col * tile_size), obj.y + (row * tile_size), obj.depth)
    }
}

This is how it looks in the level editor

Level editor with few big Smart Tile Objects
Level editor with few big Smart Tile Objects

While this is how it looks in the game

Same few big smart tiles objects. But with randomized tiles.
Same few big smart tiles objects. But with randomized tiles.

My Game Development setup

I’ll keep this short and sweet.

Whenever I tell people that I have a notebook, they usually reply with something like “and what about your main computer?”.

I do not have a “main computer”. I have just this notebook. Which is running Linux and has no accelerated graphic card available (to tell the truth it’s an integrated Intel HD Graphics 4000).

Yet I’m using GameMaker Studio. How is that even possible? VirtualBox made it possible. I’m running Windows 7 inside Linux via VirtualBox.

Testing my GameMaker platformer engine.
Testing my GameMaker platformer engine.

Even though I cannot take advantage of all the graphic acceleration stuff (e.g. the awesome graphics in Hyper Light Drifter looks like shit on my notebook; Shovel Knight is unplayable and so on…) I’m able to run my platformer engine with a decent 400 FPS (real). A consistent 60 FPS.

I’m quite happy about it but I just hope I can keep developing with this machine. Fingers crossed.

Testing the platformer engine I’ve been working on

Still in early planning stages. Yet testing the platformer engine made in GameMaker.
Still in early planning stages. Yet testing the platformer engine I made in GameMaker.

I’ll write a longer post soon. You can watch the video on youtube with some audio effects as well.

I’m still early into the planning stages of the game. I just needed a platformer engine I can work with to build the game. It’s going to be a Metroidvania type of game.

More on that later.