editor-mode-glsl.js

import CodeMirror from "codemirror";

CodeMirror.defineMode("glsl", function (config, parserConfig) {
  var indentUnit = config.indentUnit,
    keywords = parserConfig.keywords || words(glslKeywords),
    builtins = parserConfig.builtins || words(glslBuiltins),
    blockKeywords =
      parserConfig.blockKeywords ||
      words("case do else for if switch while struct"),
    atoms = parserConfig.atoms || words("null"),
    hooks = parserConfig.hooks || {},
    multiLineStrings = parserConfig.multiLineStrings;
  var isOperatorChar = /[+\-*&%=<>!?|\/]/;

  var curPunc;

  function tokenBase(stream, state) {
    var ch = stream.next();
    if (hooks[ch]) {
      var result = hooks[ch](stream, state);
      if (result !== false) return result;
    }
    if (ch == '"' || ch == "'") {
      state.tokenize = tokenString(ch);
      return state.tokenize(stream, state);
    }
    if (/[\[\]{}\(\),;\:\.]/.test(ch)) {
      curPunc = ch;
      return "bracket";
    }
    if (/\d/.test(ch)) {
      stream.eatWhile(/[\w\.]/);
      return "number";
    }
    if (ch == "/") {
      if (stream.eat("*")) {
        state.tokenize = tokenComment;
        return tokenComment(stream, state);
      }
      if (stream.eat("/")) {
        stream.skipToEnd();
        return "comment";
      }
    }
    if (ch == "#") {
      stream.eatWhile(/[\S]+/);
      stream.eatWhile(/[\s]+/);
      stream.eatWhile(/[\S]+/);
      stream.eatWhile(/[\s]+/);
      return "comment";
    }
    if (isOperatorChar.test(ch)) {
      stream.eatWhile(isOperatorChar);
      return "operator";
    }
    stream.eatWhile(/[\w\$_]/);
    var cur = stream.current();
    if (keywords.propertyIsEnumerable(cur)) {
      if (blockKeywords.propertyIsEnumerable(cur)) curPunc = "newstatement";
      return "keyword";
    }
    if (builtins.propertyIsEnumerable(cur)) {
      return "builtin";
    }
    if (atoms.propertyIsEnumerable(cur)) return "atom";
    return "word";
  }

  function tokenString(quote) {
    return function (stream, state) {
      var escaped = false,
        next,
        end = false;
      while ((next = stream.next()) != null) {
        if (next == quote && !escaped) {
          end = true;
          break;
        }
        escaped = !escaped && next == "\\";
      }
      if (end || !(escaped || multiLineStrings)) state.tokenize = tokenBase;
      return "string";
    };
  }

  function tokenComment(stream, state) {
    var maybeEnd = false,
      ch;
    while ((ch = stream.next())) {
      if (ch == "/" && maybeEnd) {
        state.tokenize = tokenBase;
        break;
      }
      maybeEnd = ch == "*";
    }
    return "comment";
  }

  function Context(indented, column, type, align, prev) {
    this.indented = indented;
    this.column = column;
    this.type = type;
    this.align = align;
    this.prev = prev;
  }
  function pushContext(state, col, type) {
    return (state.context = new Context(
      state.indented,
      col,
      type,
      null,
      state.context
    ));
  }
  function popContext(state) {
    var t = state.context.type;
    if (t == ")" || t == "]" || t == "}")
      state.indented = state.context.indented;
    return (state.context = state.context.prev);
  }

  // Interface

  return {
    startState: function (basecolumn) {
      return {
        tokenize: null,
        context: new Context((basecolumn || 0) - indentUnit, 0, "top", false),
        indented: 0,
        startOfLine: true,
      };
    },

    token: function (stream, state) {
      var ctx = state.context;
      if (stream.sol()) {
        if (ctx.align == null) ctx.align = false;
        state.indented = stream.indentation();
        state.startOfLine = true;
      }
      if (stream.eatSpace()) return null;
      curPunc = null;
      var style = (state.tokenize || tokenBase)(stream, state);
      if (style == "comment" || style == "meta") return style;
      if (ctx.align == null) ctx.align = true;

      if ((curPunc == ";" || curPunc == ":") && ctx.type == "statement")
        popContext(state);
      else if (curPunc == "{") pushContext(state, stream.column(), "}");
      else if (curPunc == "[") pushContext(state, stream.column(), "]");
      else if (curPunc == "(") pushContext(state, stream.column(), ")");
      else if (curPunc == "}") {
        while (ctx.type == "statement") ctx = popContext(state);
        if (ctx.type == "}") ctx = popContext(state);
        while (ctx.type == "statement") ctx = popContext(state);
      } else if (curPunc == ctx.type) popContext(state);
      else if (
        ctx.type == "}" ||
        ctx.type == "top" ||
        (ctx.type == "statement" && curPunc == "newstatement")
      )
        pushContext(state, stream.column(), "statement");
      state.startOfLine = false;
      return style;
    },

    indent: function (state, textAfter) {
      if (state.tokenize != tokenBase && state.tokenize != null) return 0;
      var firstChar = textAfter && textAfter.charAt(0),
        ctx = state.context,
        closing = firstChar == ctx.type;
      if (ctx.type == "statement")
        return ctx.indented + (firstChar == "{" ? 0 : indentUnit);
      else if (ctx.align) return ctx.column + (closing ? 0 : 1);
      else return ctx.indented + (closing ? 0 : indentUnit);
    },

    electricChars: "{}",
  };
});

function words(str) {
  var obj = {},
    words = str.split(" ");
  for (var i = 0; i < words.length; ++i) obj[words[i]] = true;
  return obj;
}
var glslKeywords =
  "attribute const uniform varying break continue " +
  "do for while if else in out inout float int void bool true false " +
  "lowp mediump highp precision invariant discard return mat2 mat3 " +
  "mat4 vec2 vec3 vec4 ivec2 ivec3 ivec4 bvec2 bvec3 bvec4 sampler2D " +
  "samplerCube struct gl_FragCoord gl_FragColor";
var glslBuiltins =
  "radians degrees sin cos tan asin acos atan pow " +
  "exp log exp2 log2 sqrt inversesqrt abs sign floor ceil fract mod " +
  "min max clamp mix step smoothstep length distance dot cross " +
  "normalize faceforward reflect refract matrixCompMult lessThan " +
  "lessThanEqual greaterThan greaterThanEqual equal notEqual any all " +
  "not dFdx dFdy fwidth texture2D texture2DProj texture2DLod " +
  "texture2DProjLod textureCube textureCubeLod require export";

function cppHook(stream, state) {
  if (!state.startOfLine) return false;
  stream.skipToEnd();
  return "meta";
}

(function () {
  // C#-style strings where "" escapes a quote.
  function tokenAtString(stream, state) {
    var next;
    while ((next = stream.next()) != null) {
      if (next == '"' && !stream.eat('"')) {
        state.tokenize = null;
        break;
      }
    }
    return "string";
  }

  CodeMirror.defineMIME("text/x-glsl", {
    name: "glsl",
    keywords: words(glslKeywords),
    builtins: words(glslBuiltins),
    blockKeywords: words("case do else for if switch while struct"),
    atoms: words("null"),
    hooks: { "#": cppHook },
  });
})();