fork from https://github.com/mozilla/pdf.js.git

src/core/cff_font.js

@@ -0,0 +1,140 @@
+/* Copyright 2012 Mozilla Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import { CFFCompiler, CFFParser } from "./cff_parser.js";
+import { SEAC_ANALYSIS_ENABLED, type1FontGlyphMapping } from "./fonts_utils.js";
+import { warn } from "../shared/util.js";
+
+class CFFFont {
+  constructor(file, properties) {
+    this.properties = properties;
+
+    const parser = new CFFParser(file, properties, SEAC_ANALYSIS_ENABLED);
+    this.cff = parser.parse();
+    this.cff.duplicateFirstGlyph();
+    const compiler = new CFFCompiler(this.cff);
+    this.seacs = this.cff.seacs;
+    try {
+      this.data = compiler.compile();
+    } catch (ex) {
+      warn(`Failed to compile font "${properties.loadedName}": "${ex}".`);
+      // There may have just been an issue with the compiler, set the data
+      // anyway and hope the font loaded.
+      file.reset();
+      this.data = file.getBytes();
+    }
+    this._createBuiltInEncoding();
+  }
+
+  get numGlyphs() {
+    return this.cff.charStrings.count;
+  }
+
+  getCharset() {
+    return this.cff.charset.charset;
+  }
+
+  getGlyphMapping() {
+    const cff = this.cff;
+    const properties = this.properties;
+    const { cidToGidMap, cMap } = properties;
+    const charsets = cff.charset.charset;
+    let charCodeToGlyphId;
+    let glyphId;
+
+    if (properties.composite) {
+      let invCidToGidMap;
+      if (cidToGidMap?.length > 0) {
+        invCidToGidMap = Object.create(null);
+        for (let i = 0, ii = cidToGidMap.length; i < ii; i++) {
+          const gid = cidToGidMap[i];
+          if (gid !== undefined) {
+            invCidToGidMap[gid] = i;
+          }
+        }
+      }
+
+      charCodeToGlyphId = Object.create(null);
+      let charCode;
+      if (cff.isCIDFont) {
+        // If the font is actually a CID font then we should use the charset
+        // to map CIDs to GIDs.
+        for (glyphId = 0; glyphId < charsets.length; glyphId++) {
+          const cid = charsets[glyphId];
+          charCode = cMap.charCodeOf(cid);
+
+          if (invCidToGidMap?.[charCode] !== undefined) {
+            // According to the PDF specification, see Table 117, it's not clear
+            // that a /CIDToGIDMap should be used with any non-TrueType fonts,
+            // however it's necessary to do so in order to fix issue 15559.
+            //
+            // It seems, in the CFF-case, that the /CIDToGIDMap needs to be used
+            // "inverted" compared to the TrueType-case. Here it thus seem to be
+            // a charCode mapping, rather than the normal CID to GID mapping.
+            charCode = invCidToGidMap[charCode];
+          }
+          charCodeToGlyphId[charCode] = glyphId;
+        }
+      } else {
+        // If it is NOT actually a CID font then CIDs should be mapped
+        // directly to GIDs.
+        for (glyphId = 0; glyphId < cff.charStrings.count; glyphId++) {
+          charCode = cMap.charCodeOf(glyphId);
+          charCodeToGlyphId[charCode] = glyphId;
+        }
+      }
+      return charCodeToGlyphId;
+    }
+
+    let encoding = cff.encoding ? cff.encoding.encoding : null;
+    if (properties.isInternalFont) {
+      encoding = properties.defaultEncoding;
+    }
+    charCodeToGlyphId = type1FontGlyphMapping(properties, encoding, charsets);
+    return charCodeToGlyphId;
+  }
+
+  hasGlyphId(id) {
+    return this.cff.hasGlyphId(id);
+  }
+
+  /**
+   * @private
+   */
+  _createBuiltInEncoding() {
+    const { charset, encoding } = this.cff;
+    if (!charset || !encoding) {
+      return;
+    }
+    const charsets = charset.charset,
+      encodings = encoding.encoding;
+    const map = [];
+
+    for (const charCode in encodings) {
+      const glyphId = encodings[charCode];
+      if (glyphId >= 0) {
+        const glyphName = charsets[glyphId];
+        if (glyphName) {
+          map[charCode] = glyphName;
+        }
+      }
+    }
+    if (map.length > 0) {
+      this.properties.builtInEncoding = map;
+    }
+  }
+}
+
+export { CFFFont };