Skip to main content
Version: 0.12

Shader Effect

etro.effect.Shader is the base class for all effects that render the target with a custom GLSL fragment shader.

When using this effect, you need to provide a fragment shader source and a list of uniforms. The uniforms are automatically updated when the effect is applied. There needs to be a property with the same name as each custom uniform in the effect class. The property can be a Dynamic or a regular value.

Usage​

class MyEffect extends etro.effect.Shader {
  foo: Dynamic<number>;

  constructor(foo: Dynamic<number> = 1) {
    super({
      fragmentSource: `
        precision mediump float;

        uniform sampler2D u_Source;
        uniform ivec2 u_Size;
        uniform float u_Foo;

        varying vec2 v_TextureCoord;

        void main() {
          vec4 color = texture2D(u_Source, v_TextureCoord);
          gl_FragColor = vec4(color.rgb * u_Foo, color.a);
        }
      `,
      uniforms: {
        foo: "1f",
      },
    });

    this.foo = foo;
  }
}

const effect = new MyEffect(() => Math.random());

Inheritance​

etro.effect.Shader inherits from etro.effect.Visual.

Options​

fragmentSource​

The GLSL fragment shader source.

uniforms​

A map of uniforms to their types. The types are the same as the ones used in the uniform keyword in GLSL. For example, 1f is a float, 1i is an integer, and 2f is a 2D vector.

textures​

A map of additional texture uniforms to TextureOptions. The source texture is always available as u_Source, so there is no need to add it here. See TextureOptions.

sourceTextureOptions​

Options for the source texture. See TextureOptions.

TextureOptions​

caution

These options are experimental and may change in the future.

createUniform​

If set to false, the texture uniform will not be created. This is useful if you want to create the uniform yourself. Defaults to true.

The uniform will be created with the name u_${name}.

target​

The WebGL texture target. Defaults to 'TEXTURE_2D'.

level​

The mipmap level. Defaults to 0.

internalFormat​

The internal format. Defaults to 'RGBA'.

srcFormat​

The source format. Defaults to 'RGBA'.

srcType​

The source type. Defaults to 'UNSIGNED_BYTE'.

minFilter​

The minification filter. Defaults to 'LINEAR'.

magFilter​

The magnification filter. Defaults to 'LINEAR'.

wrapS​

The horizontal wrapping mode. Defaults to 'CLAMP_TO_EDGE'.

wrapT​

The vertical wrapping mode. Defaults to 'CLAMP_TO_EDGE'.