1 /*
2 * Copyright 2013 Google Inc.
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
7
8 #include "gl/GrGLExtensions.h"
9 #include "gl/GrGLDefines.h"
10 #include "gl/GrGLUtil.h"
11
12 #include "SkJSONWriter.h"
13 #include "SkMakeUnique.h"
14 #include "SkTSearch.h"
15 #include "SkTSort.h"
16
17 namespace { // This cannot be static because it is used as a template parameter.
extension_compare(const SkString & a,const SkString & b)18 inline bool extension_compare(const SkString& a, const SkString& b) {
19 return strcmp(a.c_str(), b.c_str()) < 0;
20 }
21 }
22
23 // finds the index of ext in strings or a negative result if ext is not found.
find_string(const SkTArray<SkString> & strings,const char ext[])24 static int find_string(const SkTArray<SkString>& strings, const char ext[]) {
25 if (strings.empty()) {
26 return -1;
27 }
28 SkString extensionStr(ext);
29 int idx = SkTSearch<SkString, extension_compare>(&strings.front(),
30 strings.count(),
31 extensionStr,
32 sizeof(SkString));
33 return idx;
34 }
35
GrGLExtensions(const GrGLExtensions & that)36 GrGLExtensions::GrGLExtensions(const GrGLExtensions& that) {
37 *this = that;
38 }
39
operator =(const GrGLExtensions & that)40 GrGLExtensions& GrGLExtensions::operator=(const GrGLExtensions& that) {
41 if (this != &that) {
42 fStrings = that.fStrings;
43 fInitialized = that.fInitialized;
44 }
45 return *this;
46 }
47
eat_space_sep_strings(SkTArray<SkString> * out,const char in[])48 static void eat_space_sep_strings(SkTArray<SkString>* out, const char in[]) {
49 if (!in) {
50 return;
51 }
52 while (true) {
53 // skip over multiple spaces between extensions
54 while (' ' == *in) {
55 ++in;
56 }
57 // quit once we reach the end of the string.
58 if ('\0' == *in) {
59 break;
60 }
61 // we found an extension
62 size_t length = strcspn(in, " ");
63 out->push_back().set(in, length);
64 in += length;
65 }
66 }
67
init(GrGLStandard standard,GrGLFunction<GrGLGetStringFn> getString,GrGLFunction<GrGLGetStringiFn> getStringi,GrGLFunction<GrGLGetIntegervFn> getIntegerv,GrGLFunction<GrEGLQueryStringFn> queryString,GrEGLDisplay eglDisplay)68 bool GrGLExtensions::init(GrGLStandard standard,
69 GrGLFunction<GrGLGetStringFn> getString,
70 GrGLFunction<GrGLGetStringiFn> getStringi,
71 GrGLFunction<GrGLGetIntegervFn> getIntegerv,
72 GrGLFunction<GrEGLQueryStringFn> queryString,
73 GrEGLDisplay eglDisplay) {
74 fInitialized = false;
75 fStrings.reset();
76
77 if (!getString) {
78 return false;
79 }
80
81 // glGetStringi and indexed extensions were added in version 3.0 of desktop GL and ES.
82 const GrGLubyte* verString = getString(GR_GL_VERSION);
83 GrGLVersion version = GrGLGetVersionFromString((const char*) verString);
84 if (GR_GL_INVALID_VER == version) {
85 return false;
86 }
87
88 bool indexed = version >= GR_GL_VER(3, 0);
89
90 if (indexed) {
91 if (!getStringi || !getIntegerv) {
92 return false;
93 }
94 GrGLint extensionCnt = 0;
95 getIntegerv(GR_GL_NUM_EXTENSIONS, &extensionCnt);
96 fStrings.push_back_n(extensionCnt);
97 for (int i = 0; i < extensionCnt; ++i) {
98 const char* ext = (const char*) getStringi(GR_GL_EXTENSIONS, i);
99 fStrings[i] = ext;
100 }
101 } else {
102 const char* extensions = (const char*) getString(GR_GL_EXTENSIONS);
103 if (!extensions) {
104 return false;
105 }
106 eat_space_sep_strings(&fStrings, extensions);
107 }
108 if (queryString) {
109 const char* extensions = queryString(eglDisplay, GR_EGL_EXTENSIONS);
110
111 eat_space_sep_strings(&fStrings, extensions);
112 }
113 if (!fStrings.empty()) {
114 SkTLessFunctionToFunctorAdaptor<SkString, extension_compare> cmp;
115 SkTQSort(&fStrings.front(), &fStrings.back(), cmp);
116 }
117 fInitialized = true;
118 return true;
119 }
120
has(const char ext[]) const121 bool GrGLExtensions::has(const char ext[]) const {
122 SkASSERT(fInitialized);
123 return find_string(fStrings, ext) >= 0;
124 }
125
remove(const char ext[])126 bool GrGLExtensions::remove(const char ext[]) {
127 SkASSERT(fInitialized);
128 int idx = find_string(fStrings, ext);
129 if (idx < 0) {
130 return false;
131 }
132
133 // This is not terribly effecient but we really only expect this function to be called at
134 // most a handful of times when our test programs start.
135 fStrings.removeShuffle(idx);
136 if (idx != fStrings.count()) {
137 SkTLessFunctionToFunctorAdaptor<SkString, extension_compare> cmp;
138 SkTInsertionSort(&(fStrings.operator[](idx)), &fStrings.back(), cmp);
139 }
140 return true;
141 }
142
add(const char ext[])143 void GrGLExtensions::add(const char ext[]) {
144 int idx = find_string(fStrings, ext);
145 if (idx < 0) {
146 // This is not the most effecient approach since we end up looking at all of the
147 // extensions after the add
148 fStrings.emplace_back(ext);
149 SkTLessFunctionToFunctorAdaptor<SkString, extension_compare> cmp;
150 SkTInsertionSort(&fStrings.front(), &fStrings.back(), cmp);
151 }
152 }
153
154 #ifdef SK_ENABLE_DUMP_GPU
dumpJSON(SkJSONWriter * writer) const155 void GrGLExtensions::dumpJSON(SkJSONWriter* writer) const {
156 writer->beginArray();
157 for (int i = 0; i < fStrings.count(); ++i) {
158 writer->appendString(fStrings[i].c_str());
159 }
160 writer->endArray();
161 }
162 #else
dumpJSON(SkJSONWriter * writer) const163 void GrGLExtensions::dumpJSON(SkJSONWriter* writer) const { }
164 #endif
165