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This commit is contained in:
Gunnsteinn Hall 2020-05-25 00:54:49 +00:00
parent 11dcb12637
commit e46c3fb426
2 changed files with 14 additions and 3 deletions
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11
internal/textencoding/identity.go
View File

@ -13,7 +13,12 @@ import (
"github.com/unidoc/unipdf/v3/core"
)
// IdentityEncoder represents an 2-byte identity encoding
// IdentityEncoder represents an 2-byte identity encoding.
// NOTE: In many cases this is just used to encode/decode to glyph index and does not have a unicode
// meaning, except via the ToUnicode maps.
// TODO: The use of runes as indicators for glyph indices and not-utf8 runes is not good and confusing.
// Might be better to combine the Identity encoder with a ToUnicode map and keep track of the actual
// runes and character codes, CMaps together.
type IdentityEncoder struct {
baseName string
@ -57,6 +62,7 @@ func (enc *IdentityEncoder) Decode(raw []byte) string {
// RuneToCharcode converts rune `r` to a PDF character code.
// The bool return flag is true if there was a match, and false otherwise.
// TODO: Here the `r` is an actual rune.
func (enc *IdentityEncoder) RuneToCharcode(r rune) (CharCode, bool) {
if enc.registeredMap == nil {
enc.registeredMap = map[rune]struct{}{}
@ -68,10 +74,13 @@ func (enc *IdentityEncoder) RuneToCharcode(r rune) (CharCode, bool) {
// CharcodeToRune converts PDF character code `code` to a rune.
// The bool return flag is true if there was a match, and false otherwise.
// TODO: Here the `r` is not necessarily an actual rune but a glyph index (unless both).
func (enc *IdentityEncoder) CharcodeToRune(code CharCode) (rune, bool) {
if enc.registeredMap == nil {
enc.registeredMap = map[rune]struct{}{}
}
// TODO: The rune(code) is confusing and is not an actual utf8 rune.
enc.registeredMap[rune(code)] = struct{}{}
return rune(code), true
}

6
model/font.go
View File

@ -50,6 +50,7 @@ func (font *PdfFont) SubsetRegistered() error {
case *pdfFontType0:
err := t.subsetRegistered()
if err != nil {
common.Log.Debug("Subset error: %v", err)
return err
}
if t.container != nil {
@ -401,6 +402,7 @@ func (font *PdfFont) BytesToCharcodes(data []byte) []textencoding.CharCode {
charcodes := make([]textencoding.CharCode, 0, len(data)+len(data)%2)
if font.baseFields().isCIDFont() {
// Identity only?
if len(data) == 1 {
data = []byte{0, data[0]}
}
@ -413,6 +415,7 @@ func (font *PdfFont) BytesToCharcodes(data []byte) []textencoding.CharCode {
charcodes = append(charcodes, textencoding.CharCode(b))
}
} else {
// Simple font: byte -> charcode.
for _, b := range data {
charcodes = append(charcodes, textencoding.CharCode(b))
}
@ -745,8 +748,7 @@ func (base fontCommon) isCIDFont() bool {
// newFontBaseFieldsFromPdfObject returns `fontObj` as a dictionary the common fields from that
// dictionary in the fontCommon return. If there is a problem an error is returned.
// The fontCommon is the group of fields common to all PDF fonts.
func newFontBaseFieldsFromPdfObject(fontObj core.PdfObject) (*core.PdfObjectDictionary, *fontCommon,
error) {
func newFontBaseFieldsFromPdfObject(fontObj core.PdfObject) (*core.PdfObjectDictionary, *fontCommon, error) {
font := &fontCommon{}
if obj, ok := fontObj.(*core.PdfIndirectObject); ok {