_getConstantsString() {
    const result = [];
    const { threadDim, texSize } = this;
    if (this.dynamicOutput) {
      result.push(
        'uniform ivec3 uOutputDim',
        'uniform ivec2 uTexSize'
      );
    } else {
      result.push(
        `ivec3 uOutputDim = ivec3(${threadDim[0]}, ${threadDim[1]}, ${threadDim[2]})`,
        `ivec2 uTexSize = ivec2(${texSize[0]}, ${texSize[1]})`
      );
    }
    return utils.linesToString(result);
  }
@desc Generate transpiled glsl Strings for constant parameters sent to a kernel
@returns {String} result