H2D-Shaders.md

Shaders

You can add a Shader in H2D using drawable.addShader.

var bmp = new Bitmap(hxd.Res.my_image.toTile());
var shader = new SineDeformShader();
shader.speed = 1;
shader.amplitude = .1;
shader.frequency = .5;
shader.texture = bmp.tile.getTexture();
bmp.addShader(shader);

Creating custom shaders

To create a custom shader, extend hxsl.Shader and write the shader source in static SRC. You also need to add @:import h3d.shader.Base2d;, which exposes helpful parameters (see next section).

@:import will import definitions and thus assume you have this shader as part of your pipeline.

class SineDeformShader extends hxsl.Shader {
	static var SRC = {
		@:import h3d.shader.Base2d;

		@param var texture : Sampler2D;
		@param var speed : Float;
		@param var frequency : Float;
		@param var amplitude : Float;

		function fragment() {
			calculatedUV.y += sin(calculatedUV.y * frequency + time * speed) * amplitude; // wave deform
			pixelColor = texture.get(calculatedUV);
		}
	}
}

Base 2D values

For 2D shaders, the following parameters are available in the custom shader. When in doubt, you can look these up in h3d.shader.Base2d (which you have to import).

var spritePosition : Vec4;
var absolutePosition : Vec4;
var pixelColor : Vec4;
var textureColor : Vec4;
@var var calculatedUV : Vec2;

var outputPosition : Vec4;