1 /*
2 * Copyright (c) 2011, 2012, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 #import <AppKit/AppKit.h>
27 #import "CoreTextSupport.h"
28
29
30 /*
31 * Callback for CoreText which uses the CoreTextProviderStruct to
32 * feed CT UniChars. We only use it for one-off lines, and don't
33 * attempt to fragment our strings.
34 */
35 const UniChar *
36 CTS_Provider(CFIndex stringIndex, CFIndex *charCount,
37 CFDictionaryRef *attributes, void *refCon)
38 {
39 // if we have a zero length string we can just return NULL for the string
40 // or if the index anything other than 0 we are not using core text
41 // correctly since we only have one run.
42 if (stringIndex != 0) {
43 return NULL;
44 }
45
46 CTS_ProviderStruct *ctps = (CTS_ProviderStruct *)refCon;
47 *charCount = ctps->length;
48 *attributes = ctps->attributes;
49 return ctps->unicodes;
50 }
51
52
53 #pragma mark --- Retain/Release CoreText State Dictionary ---
54
55 /*
56 * Gets a Dictionary filled with common details we want to use for CoreText
57 * when we are interacting with it from Java.
58 */
59 static inline CFMutableDictionaryRef
60 GetCTStateDictionaryFor(const NSFont *font, BOOL useFractionalMetrics)
61 {
62 NSNumber *gZeroNumber = [NSNumber numberWithInt:0];
63 NSNumber *gOneNumber = [NSNumber numberWithInt:1];
64
65 CFMutableDictionaryRef dictRef = (CFMutableDictionaryRef)
66 [[NSMutableDictionary alloc] initWithObjectsAndKeys:
67 font, NSFontAttributeName,
68 // TODO(cpc): following attribute is private...
69 //gOneNumber, (id)kCTForegroundColorFromContextAttributeName,
70 // force integer hack in CoreText to help with Java integer assumptions
71 useFractionalMetrics ? gZeroNumber : gOneNumber, @"CTIntegerMetrics",
72 gZeroNumber, NSLigatureAttributeName,
73 gZeroNumber, NSKernAttributeName,
74 NULL];
75 CFRetain(dictRef); // GC
76 [(id)dictRef release];
77
78 return dictRef;
79 }
80
81 /*
82 * Releases the CoreText Dictionary - in the future we should hold on
83 * to these to improve performance.
84 */
85 static inline void
86 ReleaseCTStateDictionary(CFDictionaryRef ctStateDict)
87 {
88 CFRelease(ctStateDict); // GC
89 }
90
91 /*
92 * Transform Unicode characters into glyphs.
93 *
94 * Fills the "glyphsAsInts" array with the glyph codes for the current font,
95 * or the negative unicode value if we know the character can be hot-substituted.
96 *
97 * This is the heart of "Universal Font Substitution" in Java.
98 */
99 void CTS_GetGlyphsAsIntsForCharacters
100 (const AWTFont *font, const UniChar unicodes[], CGGlyph glyphs[], jint glyphsAsInts[], const size_t count)
101 {
102 CTFontGetGlyphsForCharacters((CTFontRef)font->fFont, unicodes, glyphs, count);
103
104 size_t i;
105 for (i = 0; i < count; i++) {
106 CGGlyph glyph = glyphs[i];
107 if (glyph > 0) {
108 glyphsAsInts[i] = glyph;
109 continue;
110 }
111
112 UniChar unicode = unicodes[i];
113 const CTFontRef fallback = JRSFontCreateFallbackFontForCharacters((CTFontRef)font->fFont, &unicode, 1);
114 if (fallback) {
115 CTFontGetGlyphsForCharacters(fallback, &unicode, &glyph, 1);
116 CFRelease(fallback);
117 }
118
119 if (glyph > 0) {
120 glyphsAsInts[i] = -unicode; // set the glyph code to the negative unicode value
121 } else {
122 glyphsAsInts[i] = 0; // CoreText couldn't find a glyph for this character either
123 }
124 }
125 }
126
127 /*
128 * Translates a Unicode into a CGGlyph/CTFontRef pair
129 * Returns the substituted font, and places the appropriate glyph into "glyphRef"
130 */
131 CTFontRef CTS_CopyCTFallbackFontAndGlyphForUnicode
132 (const AWTFont *font, const UTF16Char *charRef, CGGlyph *glyphRef, int count) {
133 CTFontRef fallback = JRSFontCreateFallbackFontForCharacters((CTFontRef)font->fFont, charRef, count);
134 if (fallback == NULL)
135 {
136 // use the original font if we somehow got duped into trying to fallback something we can't
137 fallback = (CTFontRef)font->fFont;
138 CFRetain(fallback);
139 }
140
141 CTFontGetGlyphsForCharacters(fallback, charRef, glyphRef, count);
142 return fallback;
143 }
144
145 /*
146 * Translates a Java glyph code int (might be a negative unicode value) into a CGGlyph/CTFontRef pair
147 * Returns the substituted font, and places the appropriate glyph into "glyphRef"
148 */
149 CTFontRef CTS_CopyCTFallbackFontAndGlyphForJavaGlyphCode
150 (const AWTFont *font, const jint glyphCode, CGGlyph *glyphRef)
151 {
152 // negative glyph codes are really unicodes, which were placed there by the mapper
153 // to indicate we should use CoreText to substitute the character
154 if (glyphCode >= 0)
155 {
156 *glyphRef = glyphCode;
157 CFRetain(font->fFont);
158 return (CTFontRef)font->fFont;
159 }
160
161 UTF16Char character = -glyphCode;
162 return CTS_CopyCTFallbackFontAndGlyphForUnicode(font, &character, glyphRef, 1);
163 }
164
165 // Breakup a 32 bit unicode value into the component surrogate pairs
166 void CTS_BreakupUnicodeIntoSurrogatePairs(int uniChar, UTF16Char charRef[]) {
167 int value = uniChar - 0x10000;
168 UTF16Char low_surrogate = (value & 0x3FF) | LO_SURROGATE_START;
169 UTF16Char high_surrogate = (((int)(value & 0xFFC00)) >> 10) | HI_SURROGATE_START;
170 charRef[0] = high_surrogate;
171 charRef[1] = low_surrogate;
172 }