1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/gfx/skia/trunk/src/gpu/gl/GrGLExtensions.cpp Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,142 @@
1.4 +/*
1.5 + * Copyright 2013 Google Inc.
1.6 + *
1.7 + * Use of this source code is governed by a BSD-style license that can be
1.8 + * found in the LICENSE file.
1.9 + */
1.10 +
1.11 +#include "gl/GrGLExtensions.h"
1.12 +#include "gl/GrGLDefines.h"
1.13 +#include "gl/GrGLUtil.h"
1.14 +
1.15 +#include "SkTSearch.h"
1.16 +#include "SkTSort.h"
1.17 +
1.18 +namespace { // This cannot be static because it is used as a template parameter.
1.19 +inline bool extension_compare(const SkString& a, const SkString& b) {
1.20 + return strcmp(a.c_str(), b.c_str()) < 0;
1.21 +}
1.22 +}
1.23 +
1.24 +// finds the index of ext in strings or a negative result if ext is not found.
1.25 +static int find_string(const SkTArray<SkString>& strings, const char ext[]) {
1.26 + if (strings.empty()) {
1.27 + return -1;
1.28 + }
1.29 + SkString extensionStr(ext);
1.30 + int idx = SkTSearch<SkString, extension_compare>(&strings.front(),
1.31 + strings.count(),
1.32 + extensionStr,
1.33 + sizeof(SkString));
1.34 + return idx;
1.35 +}
1.36 +
1.37 +GrGLExtensions::GrGLExtensions(const GrGLExtensions& that) : fStrings(SkNEW(SkTArray<SkString>)) {
1.38 + *this = that;
1.39 +}
1.40 +
1.41 +GrGLExtensions& GrGLExtensions::operator=(const GrGLExtensions& that) {
1.42 + *fStrings = *that.fStrings;
1.43 + fInitialized = that.fInitialized;
1.44 + return *this;
1.45 +}
1.46 +
1.47 +bool GrGLExtensions::init(GrGLStandard standard,
1.48 + GrGLGetStringProc getString,
1.49 + GrGLGetStringiProc getStringi,
1.50 + GrGLGetIntegervProc getIntegerv) {
1.51 + fInitialized = false;
1.52 + fStrings->reset();
1.53 +
1.54 + if (NULL == getString) {
1.55 + return false;
1.56 + }
1.57 +
1.58 + // glGetStringi and indexed extensions were added in version 3.0 of desktop GL and ES.
1.59 + const GrGLubyte* verString = getString(GR_GL_VERSION);
1.60 + if (NULL == verString) {
1.61 + return false;
1.62 + }
1.63 + GrGLVersion version = GrGLGetVersionFromString((const char*) verString);
1.64 + bool indexed = version >= GR_GL_VER(3, 0);
1.65 +
1.66 + if (indexed) {
1.67 + if (NULL == getStringi || NULL == getIntegerv) {
1.68 + return false;
1.69 + }
1.70 + GrGLint extensionCnt = 0;
1.71 + getIntegerv(GR_GL_NUM_EXTENSIONS, &extensionCnt);
1.72 + fStrings->push_back_n(extensionCnt);
1.73 + for (int i = 0; i < extensionCnt; ++i) {
1.74 + const char* ext = (const char*) getStringi(GR_GL_EXTENSIONS, i);
1.75 + (*fStrings)[i] = ext;
1.76 + }
1.77 + } else {
1.78 + const char* extensions = (const char*) getString(GR_GL_EXTENSIONS);
1.79 + if (NULL == extensions) {
1.80 + return false;
1.81 + }
1.82 + while (true) {
1.83 + // skip over multiple spaces between extensions
1.84 + while (' ' == *extensions) {
1.85 + ++extensions;
1.86 + }
1.87 + // quit once we reach the end of the string.
1.88 + if ('\0' == *extensions) {
1.89 + break;
1.90 + }
1.91 + // we found an extension
1.92 + size_t length = strcspn(extensions, " ");
1.93 + fStrings->push_back().set(extensions, length);
1.94 + extensions += length;
1.95 + }
1.96 + }
1.97 + if (!fStrings->empty()) {
1.98 + SkTLessFunctionToFunctorAdaptor<SkString, extension_compare> cmp;
1.99 + SkTQSort(&fStrings->front(), &fStrings->back(), cmp);
1.100 + }
1.101 + fInitialized = true;
1.102 + return true;
1.103 +}
1.104 +
1.105 +bool GrGLExtensions::has(const char ext[]) const {
1.106 + SkASSERT(fInitialized);
1.107 + return find_string(*fStrings, ext) >= 0;
1.108 +}
1.109 +
1.110 +bool GrGLExtensions::remove(const char ext[]) {
1.111 + SkASSERT(fInitialized);
1.112 + int idx = find_string(*fStrings, ext);
1.113 + if (idx >= 0) {
1.114 + // This is not terribly effecient but we really only expect this function to be called at
1.115 + // most a handful of times when our test programs start.
1.116 + SkAutoTDelete< SkTArray<SkString> > oldStrings(fStrings.detach());
1.117 + fStrings.reset(SkNEW(SkTArray<SkString>(oldStrings->count() - 1)));
1.118 + fStrings->push_back_n(idx, &oldStrings->front());
1.119 + fStrings->push_back_n(oldStrings->count() - idx - 1, &(*oldStrings)[idx] + 1);
1.120 + return true;
1.121 + } else {
1.122 + return false;
1.123 + }
1.124 +}
1.125 +
1.126 +void GrGLExtensions::add(const char ext[]) {
1.127 + int idx = find_string(*fStrings, ext);
1.128 + if (idx < 0) {
1.129 + // This is not the most effecient approach since we end up doing a full sort of the
1.130 + // extensions after the add
1.131 + fStrings->push_back().set(ext);
1.132 + SkTLessFunctionToFunctorAdaptor<SkString, extension_compare> cmp;
1.133 + SkTQSort(&fStrings->front(), &fStrings->back(), cmp);
1.134 + }
1.135 +}
1.136 +
1.137 +void GrGLExtensions::print(const char* sep) const {
1.138 + if (NULL == sep) {
1.139 + sep = " ";
1.140 + }
1.141 + int cnt = fStrings->count();
1.142 + for (int i = 0; i < cnt; ++i) {
1.143 + GrPrintf("%s%s", (*fStrings)[i].c_str(), (i < cnt - 1) ? sep : "");
1.144 + }
1.145 +}
