Messy Mind » tutorials

High quality terrain/tile transitions

GearGOD — Mon, 22 Oct 2007 03:33:18 +0000

A few nights ago a magical fairy came to me in my dreams and told me, ‘all those executables which you lost the editables to, they’re actually editables!’ I thought the fairy was full of shit but what do you know, the next morning I looked in my GM folder and lo and behold, there appeared editables for things I lost the source to!

In celebration, here is the editable to something really neat I wrote a while ago. It’s a ridiculously fast (for what it does) terrain renderer which supports spec highlights and I would bet, beats using tiles on occassion. It’s an extension of my metaballs rendering concept applied across any number of tile layers without involving a second surface.
It’s just a proof of concept for an idea I never got to finish and polish, but hey so is a lot of other stuff I put here. Once again, look, learn, use. Or, attempt to blindly integrate it in your game and hope for the best.

Oh by the way. It was written back in gm6, and gm6 had a stupid bug to do with surfaces, which I had to cheat around. In gm7 it seems to have been dealt with so my workaround actually causes the inverse of the bug to happen. So if you’re using it in gm7, open the startup script and change the values of fx and fy to 1.

Surface Based Terrain

Lumines type ’scanner’ with fireflies

GearGOD — Tue, 16 Oct 2007 05:43:52 +0000

Something neat I ran into today; a little proof of concept for a Lumines kind of effect. Only, prettier.

Fireflies

Realtime Dynamic Light

GearGOD — Sun, 07 Oct 2007 01:28:19 +0000

This is a little bit of history, the very first lighting system for game maker. Prior it was thought impossible to achieve. It works quite different from its modern cousins because surfaces didn’t exist back in the day. It’s obviously not for actual use, I thought thought it would be nice a post a page in GM history. Although several people have emailed me about it, one even intending to use it. I’m not sure why, but here you go.

While the thing itself is outdated, it still shows some good things to learn from like drawing smooth outlines around sprites and some uses for luminance scan, which you’ll find in every modern lighting engine.

Realtime Dynamic Light

Smooth loading bar

GearGOD — Thu, 04 Oct 2007 19:44:31 +0000

You might have seen this as part of an older GUI demo I posted. It’s a really smooth circular progressbar type thing. I just ran into it and thought it’d be nice to share. I still have to figure out what to do with my smaller creations.
Incidentally, I went and found the demo in question and linked it here, even though I’ve lost the source to that particular build and can only offer an exe. I still think its a good little demo to look at as it demonstrates a number of things I takled about working in concert: interface, eyecandy, my object importer (here it is used to fetch content from the web and run it). You’ll find the demo at 64digits.

As for the sample itself… Progress ring.
And don’t fret, the editable for my GUI in it’s latest form is coming.

2D Metaballs

GearGOD — Wed, 03 Oct 2007 00:00:35 +0000

The challange was to draw a 2d fluid. The solution was very interesting. Because actually solving marching cubes or similar was too slow in Game Maker, I designed an ‘analog’ approach. This works on a surface. First we draw whatever the fluid ‘world’ may be – that is, what the fluid area will actually show. Like a liquidy red version of the screen for blood, or a gradienty blue version for water, etc. Then we do a bit of magic and overwrite the alpha of that surface with the alpha of particles representing the fluid area. Last but not least, we achieve thresholding without alpha testing which is unsvailable in game maker by multiplying the alpha values by themselves several times much like the contrast ramp phase of a bloom filter.

The technique of overwriting a surface’s alpha chanel alone is useful in many other applications, but I’ll let you think about that.
Oh yeah one more thing. The demo itself looks different from both these screenshots. And probably less pretty. Fiddle with it yourself to achieve the style you want. You’ll be wanting to play with the step script, which is sufficiently commented to navigate.

Metaballs!

Shockwave

GearGOD — Tue, 02 Oct 2007 22:57:53 +0000

This is a little distorting shockwave effect. You might remember it from my very impressive Kill Catalyst screenshots on 64digits. It’s not quite so impressive in the demo, but if tweaked a bit and used right, will be awesome.

Shockwaves

Distorting Energy Beams

GearGOD — Tue, 02 Oct 2007 22:51:51 +0000

This is really neat. It’s a few things in one. First and foremost it handles linear screenspace distortions. We’ve done shockwave rings, but lines turned out to be a bit more tricky. This shows two methods of doing it. One very pretty but slow one by creating several point distortions, and one fast but less pretty one with a few quads. It also shows how to do lightning that follows a linear path, and how to go about making awesome energy beams in general.

As with must stuff coming out of my GM folder, there’s no help file or explanations. If you want to use this, you’re going to have to pull it out yourself.

Linear distortion

Perspective correct texturing without d3d

GearGOD — Tue, 02 Oct 2007 18:41:04 +0000

I whipped this up after someone posted on the GMC asking about it. Mark’s naiive approach to drawing in version 6 and above resulted in it having a d3d and normal mode when both are esentially the same thing. Enabling d3d makes a number of things impossible. Mainly, surfaces. Not having d3d makes other things impossible like zbuffer and perspective correct texturing.

If you ever try to draw a skewed or distorted polygon with textures, you’ll see that there’s a weird artifact. Unfortunely only Mark can fix this, but we can approximate a solution by subdividing our polygon into several segments and interpolating the texture coordinates for them. By providing properly calculated UVs to each segment, we reduce the error the renderer produces by giving it more clues as to what the UV values should actually be.

Perspective Correct Texturing

Textured ribbon trails

GearGOD — Tue, 02 Oct 2007 14:25:29 +0000

Ribbon trails are very pretty if used right. In fact even if used wrong they’re still pretty most of the time. I don’t know why no one has done this before. I saw scripts that drew them with circles which gets slow or ugly if you go fast, and with lines, which is limited to 1px in width. The obvious thing to do of course is to use a primitive.
So we make a list containing coords of where we’ve been for the past N steps, and then draw it. I’m not going to explain the intricacies of the drawing script but everything is very straightforward and you shouldn’t have problems figuring out how to use it.

When doing mouse decorations or trails, never have them snap to the mouse position! The mouse is a precise input device which is good most of the time but in the land of eyecandy it means jerky, ugly movements. Instead have the decoration follow slowly as I do here. It makes a world of difference.

Ribbon trails

Luminaire

GearGOD — Tue, 02 Oct 2007 14:00:01 +0000

Luminaire… The start of the GM lighting era. This was developed shortly after GM6.1 was released with the new surfaces feature which I’ve been hammering mark about. It is old, outdated, and horribly inefficient because I was rushing to release it and show everyone that this can be done. Compared to it’s modern cousins like L3S, it’s not very much, but people have been continuously asking for it regardless. I don’t know why, but here it is.

I wouldn’t recommend using it in a serious game where L3S would really shine , but for smaller ones it should be just fine. The other thing you can learn from it is the way the engine is used to set the mood in a scene. I think the reason people still pick this over modern, better engines is because the demo is gorgeous. The others don’t do too well in this area. So look at the demo and learn how the eyecandy works. Notice how the lights fade in and out, notice the lights overhead, the use of glow. All these things aren’t technically complicated but add up to the ‘wow’ effect.
Look at it and learn from it, but you should really be using L3S or similar if you use a lighting engine. Make no mistake about it, this is a first generation lighting engine. In fact it’s the first lighting engine. It’s really oooooold! We’re now in 3rd gen dynamic soft shadows age!

Game info contains everything you’ll need to know to use this.

Luminaire