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39
40#ifndef QOPENGLTEXTUREGLYPHCACHE_P_H
41#define QOPENGLTEXTUREGLYPHCACHE_P_H
42
43//
44// W A R N I N G
45// -------------
46//
47// This file is not part of the Qt API. It exists purely as an
48// implementation detail. This header file may change from version to
49// version without notice, or even be removed.
50//
51// We mean it.
52//
53
54#include <QtGui/private/qtguiglobal_p.h>
55#include <private/qtextureglyphcache_p.h>
56#include <private/qopenglcontext_p.h>
57#include <qopenglshaderprogram.h>
58#include <qopenglfunctions.h>
59#include <qopenglbuffer.h>
60#include <qopenglvertexarrayobject.h>
61
62// #define QT_GL_TEXTURE_GLYPH_CACHE_DEBUG
63
64QT_BEGIN_NAMESPACE
65
66class QOpenGL2PaintEngineExPrivate;
67
68class QOpenGLGlyphTexture : public QOpenGLSharedResource
69{
70public:
71 explicit QOpenGLGlyphTexture(QOpenGLContext *ctx)
72 : QOpenGLSharedResource(ctx->shareGroup())
73 , m_width(0)
74 , m_height(0)
75 {
76 if (!ctx->d_func()->workaround_brokenFBOReadBack)
77 QOpenGLFunctions(ctx).glGenFramebuffers(n: 1, framebuffers: &m_fbo);
78
79#ifdef QT_GL_TEXTURE_GLYPH_CACHE_DEBUG
80 qDebug(" -> QOpenGLGlyphTexture() %p for context %p.", this, ctx);
81#endif
82 }
83
84 void freeResource(QOpenGLContext *context) override
85 {
86 QOpenGLContext *ctx = context;
87#ifdef QT_GL_TEXTURE_GLYPH_CACHE_DEBUG
88 qDebug("~QOpenGLGlyphTexture() %p for context %p.", this, ctx);
89#endif
90 if (!ctx->d_func()->workaround_brokenFBOReadBack)
91 ctx->functions()->glDeleteFramebuffers(n: 1, framebuffers: &m_fbo);
92 if (m_width || m_height)
93 ctx->functions()->glDeleteTextures(n: 1, textures: &m_texture);
94 }
95
96 void invalidateResource() override
97 {
98 m_texture = 0;
99 m_fbo = 0;
100 m_width = 0;
101 m_height = 0;
102 }
103
104 GLuint m_texture;
105 GLuint m_fbo;
106 int m_width;
107 int m_height;
108};
109
110class Q_GUI_EXPORT QOpenGLTextureGlyphCache : public QImageTextureGlyphCache
111{
112public:
113 QOpenGLTextureGlyphCache(QFontEngine::GlyphFormat glyphFormat, const QTransform &matrix, const QColor &color = QColor());
114 ~QOpenGLTextureGlyphCache();
115
116 virtual void createTextureData(int width, int height) override;
117 virtual void resizeTextureData(int width, int height) override;
118 virtual void fillTexture(const Coord &c, glyph_t glyph, QFixed subPixelPosition) override;
119 virtual int glyphPadding() const override;
120 virtual int maxTextureWidth() const override;
121 virtual int maxTextureHeight() const override;
122
123 inline GLuint texture() const {
124 QOpenGLTextureGlyphCache *that = const_cast<QOpenGLTextureGlyphCache *>(this);
125 QOpenGLGlyphTexture *glyphTexture = that->m_textureResource;
126 return glyphTexture ? glyphTexture->m_texture : 0;
127 }
128
129 inline int width() const {
130 QOpenGLTextureGlyphCache *that = const_cast<QOpenGLTextureGlyphCache *>(this);
131 QOpenGLGlyphTexture *glyphTexture = that->m_textureResource;
132 return glyphTexture ? glyphTexture->m_width : 0;
133 }
134 inline int height() const {
135 QOpenGLTextureGlyphCache *that = const_cast<QOpenGLTextureGlyphCache *>(this);
136 QOpenGLGlyphTexture *glyphTexture = that->m_textureResource;
137 return glyphTexture ? glyphTexture->m_height : 0;
138 }
139
140 inline void setPaintEnginePrivate(QOpenGL2PaintEngineExPrivate *p) { pex = p; }
141
142 inline const QOpenGLContextGroup *contextGroup() const { return m_textureResource ? m_textureResource->group() : nullptr; }
143
144 inline int serialNumber() const { return m_serialNumber; }
145
146 enum FilterMode {
147 Nearest,
148 Linear
149 };
150 FilterMode filterMode() const { return m_filterMode; }
151 void setFilterMode(FilterMode m) { m_filterMode = m; }
152
153 void clear();
154
155 QOpenGL2PaintEngineExPrivate *paintEnginePrivate() const
156 {
157 return pex;
158 }
159
160private:
161 void setupVertexAttribs();
162
163 QOpenGLGlyphTexture *m_textureResource;
164
165 QOpenGL2PaintEngineExPrivate *pex;
166 QOpenGLShaderProgram *m_blitProgram;
167 FilterMode m_filterMode;
168
169 GLfloat m_vertexCoordinateArray[8];
170 GLfloat m_textureCoordinateArray[8];
171
172 int m_serialNumber;
173
174 QOpenGLBuffer m_buffer;
175 QOpenGLVertexArrayObject m_vao;
176};
177
178QT_END_NAMESPACE
179
180#endif // QOPENGLTEXTUREGLYPHCACHE_P_H
181
182

source code of qtbase/src/gui/opengl/qopengltextureglyphcache_p.h