VideoShader

VideoShader.ts

namespace trio {

  var vertexShader = `
    precision lowp float;
    attribute vec2 aVertexPosition;
    attribute vec2 aTextureCoord;
    attribute vec4 aColor;

    uniform mat3 projectionMatrix;

    varying vec2 vTextureCoord;
    varying vec4 vColor;

    void main(void){
      gl_Position = vec4((projectionMatrix * vec3(aVertexPosition, 1.0)).xy, 0.0, 1.0);
      vTextureCoord = aTextureCoord;
      vColor = vec4(aColor.rgb * aColor.a, aColor.a);
    }`;

  var fragmentShader = `
      precision lowp float;

      varying vec2 vTextureCoord;
      varying vec4 vColor;

      uniform sampler2D uSampler;

      void main(void) {
        float texelAlpha = texture2D(uSampler, vec2(vTextureCoord.s, vTextureCoord.t * 0.5 + 0.5)).r;
        vec4 color = texture2D(uSampler, vec2(vTextureCoord.s, vTextureCoord.t * 0.5)) * vColor;
        gl_FragColor = vec4(color.rgb, color.a * texelAlpha);
      }`;

  export class VideoShader extends PIXI.Shader {
    constructor(shaderManager: PIXI.ShaderManager) {
      var uniforms = {
          uSampler: { type: 'sampler2D', value: 0 },
          projectionMatrix: { type: 'mat3', value: new Float32Array([1, 0, 0,
                                                                     0, 1, 0,
                                                                     0, 0, 1]) }
      };
      var attributes = {
          aVertexPosition: 0,
          aTextureCoord: 0,
          aColor: 0
      };
      super(shaderManager, vertexShader, fragmentShader, uniforms, attributes);
    }
  }
}