gl-utils.js

function loadShader(gl, type, source) {
  const shader = gl.createShader(type);
  gl.shaderSource(shader, source);
  gl.compileShader(shader);

  if (!gl.getShaderParameter(shader, gl.COMPILE_STATUS)) {
    alert(
      `Terjadi kesalahan saat proses kompilasi shaders: ${gl.getShaderInfoLog(
        shader
      )}`
    );
    gl.deleteShader(shader);
    return null;
  }

  return shader;
}

function initShaderProgram(gl, vsSource, fsSource) {
  const vertexShader = loadShader(gl, gl.VERTEX_SHADER, vsSource);
  const fragmentShader = loadShader(gl, gl.FRAGMENT_SHADER, fsSource);
  const shaderProgram = gl.createProgram();
  gl.attachShader(shaderProgram, vertexShader);
  gl.attachShader(shaderProgram, fragmentShader);
  gl.linkProgram(shaderProgram);

  if (!gl.getProgramParameter(shaderProgram, gl.LINK_STATUS)) {
    alert(
      `Tidak dapat menginisialisasi program shader: ${gl.getProgramInfoLog(
        shaderProgram
      )}`
    );
    return false;
  }
  gl.program = shaderProgram;
  return true;
}