RT @HeartMachineZ: If you or anyone you know is a topnotch GameMaker programmer and interested in helping us with a few things, hit up info… (Today)

@RakurinHD It was Ibuki who I was kinda interested in checking out so maybe it was just destiny (Today)

@Capy_Nathan I think I still like 4 better but that is probably just due to how much time I spent with it, and 5 doesn't have sak ;_; (Today)

@Capy_Nathan hmm yeah I am having fun with mika, karin, and juri but right now the characters feel more samey than they did in SF4 maybe? (Today)

@mattjbaldo It purchased it with my fight money which is the first option in the menu, so when it buffered my input it just selected that. (Today)

@Capy_Nathan yes the core game is really fun and cool and great which is why I am so dang frustrated at everything else (Today)

I cannot help but laugh at what a horrible mess SFV is other than the actual core game itself. It amazes me more and more every day. (Today)

accidentally bought a character in street fighter v because I tried to select a locked char and it lagged and I hit A during the lag fffffff (Today)

@aceriou not an otter thing. You could use some windows api methods on init to force focus I believe. (Yesterday)

@aceriou yeah sorry that's something in windows I think. When you run without debug console it should just focus the game window (Yesterday)

@TyrusPeace I hear guilty gear is pretty good. The new KoF looks... weird. I liked KoF13 a lot though. (Yesterday)

@RakurinHD Yeah they look... alright? But dang between the UI, survival mode, and the excessive DLC I'm amazed it has players (Yesterday)

I like the core system and fighting part of street fighter v but wow everything else surrounding it stinky poop garbage (Yesterday)

@aceriou There was a Flashpunk "port" to C++, and Otter is based off Flashpunk: t.co/PBf41S4KRh Hasn't been touched in awhile though (2 days ago)

@aceriou Not sure, but if you're using C++ I would look into just using SFML directly, or look into C++ built frameworks rather than Otter. (2 days ago)

@StoryFort yaye yaaaaaaye (2 days ago)

@dejobaan I'M FIRED (2 days ago)

Working solo is cool and all but it also means that when I'm in a huge funk I don't have anyone else on the project to snap me out of it x_x (2 days ago)

RT @x01010111: If YOU help make @HaxeFlixel better, I can make better games for YOU to play!!! t.co/glJDPr5Oiw #indiedev t.… (2 days ago)

RT @gabetelepak: I'm looking for freelance design work to pay the bills! Plz RT 🙏 I have a wife + two fat pugs to feed t.co/TPdeMq… (2 days ago)

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2014 - 6 - 2 / 4:09 pm / general

Dev Log: Shader Experiments

Dev Log: Shader Experiments

Since my break to work on the remaining bits of Otter I haven't really fallen back into the groove on working on my big game project yet. Yesterday I dedicated the day to playing around with shaders since I'm really interested in using them for all kinds of cool visual effects.

Image

This is what I ended up coming up with at the end of the day. First I was playing around with gradient maps for recoloring an image, and then I started to mess with displacement to make cool waves in the image. Finally I wanted to experiment with having a render texture that could be passed to the shader for dynamic effects.

Basically how this little program works is that there is the static image with a shader loaded. Then there's a Surface object that can be painted on with the mouse. The shader uses the texture from that Surface to affect the image in different ways.

Here's the full C# source:

using Otter;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace ShaderTesting {
class Program {
static void Main(string[] args) {
var image = new Image("pic.jpg");
var game = new Game("ShaderZ", image.Width, image.Height);

game.FirstScene = new TestScene();

game.Start();
}
}

class TestScene : Scene {

Image image = new Image("pic.jpg");
Image circle = new Image("circle.png");
Surface distortion;

public TestScene() {
AddGraphic(image);
distortion = new Surface(image.Width, image.Height);
circle.CenterOrigin();
circle.Blend = BlendMode.Add;
AddGraphic(distortion);
circle.Alpha = 0.1f;
distortion.Visible = false;
distortion.AutoClear = false;
}

public override void Update() {
base.Update();

if (Timer % 30 == 0) {
try {
image.Shader = new Shader("../../shader.frag");
}
catch(Exception e) {
Console.WriteLine("Shader error:");
Console.WriteLine(e.Message);
}
image.Shader.SetParameter("gradient", new Texture("gradient.png"));
}
if (Input.MouseButtonPressed(MouseButton.Right)) {
distortion.Clear();
}
image.Shader.SetParameter("time", Timer);
image.Shader.SetParameter("distortion", distortion.Texture);
image.Shader.SetParameter("offset", Util.SinScale(Timer, 0, 1));

if (Input.MouseButtonDown(MouseButton.Left)) {
Draw.SetTarget(distortion);
Draw.Graphic(circle, MouseX, image.Height - MouseY);
Draw.ResetTarget();
}
}

public override void Render() {
base.Render();

Draw.Circle(MouseX - 15, MouseY - 15, 30, Color.None, Color.Red, 2);
}
}
}


And the GLSL shader source:

sampler2D texture;
sampler2D gradient;
sampler2D distortion;
uniform float offset;
uniform float time;
uniform float mixfactor;

void main() {
vec2 pos = gl_TexCoord[0];
vec2 distortColor = texture2D(distortion, pos);
pos.x += distortColor.r * (sin(time * 0.1 + pos.x * 10) * 0.05);
pos.y -= distortColor.g * (cos(time * 0.1 + pos.y * 10) * 0.05);
vec4 color = texture2D(texture, pos);

float gray = (color.r + color.g + color.b) / 3;

vec4 gradientColor = texture2D(gradient, vec2(gray, offset));

gl_FragColor = mix(color, gradientColor, distortColor.r + distortColor.g);
}


You can download everything here. Note that you'll have to give it a reference to Otter to compile and run it yourself.

2 Comments
Avatar

2014 - 6 - 10 9:57 PM

R Brack

Are you meant to be creating a new shader and texture every 30 (seconds? milliseconds?) That seems a bit rough to me.

Avatar

2014 - 6 - 11 1:25 AM

Kyle

It's actually every half second (60 fps.) It's so I can edit the shader, save, and see my changes almost instantly instead of having to rebuild the application. I don't notice any performance issues.

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Hi! My name's Kyle, and I make video games most of the time in Denver, Colorado. Here you will find my thoughts, games, websites, doodles, and other stuff like that. I worked on Snapshot, Offspring Fling, and a whole bunch of other games. I also created and maintain Otter, a 2d game making framework. If you want to get a hold of me use the form on the bottom of the page, leave a comment, or just tweet at me. I try to post three times a week. Thanks for stoppin' by! You're the coolest.

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