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39
40#ifndef QTEXTUREGLYPHCACHE_GL_P_H
41#define QTEXTUREGLYPHCACHE_GL_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 <private/qtextureglyphcache_p.h>
55#include <private/qgl_p.h>
56#include <qglshaderprogram.h>
57#include <qglframebufferobject.h>
58#include <qopenglfunctions.h>
59
60// #define QT_GL_TEXTURE_GLYPH_CACHE_DEBUG
61
62QT_BEGIN_NAMESPACE
63
64class QGL2PaintEngineExPrivate;
65
66struct QGLGlyphTexture : public QOpenGLSharedResource
67{
68 QGLGlyphTexture(const QGLContext *ctx)
69 : QOpenGLSharedResource(ctx->contextHandle()->shareGroup())
70 , m_fbo(0)
71 , m_width(0)
72 , m_height(0)
73 {
74 if (ctx && QGLFramebufferObject::hasOpenGLFramebufferObjects() && !ctx->d_ptr->workaround_brokenFBOReadBack)
75 ctx->contextHandle()->functions()->glGenFramebuffers(n: 1, framebuffers: &m_fbo);
76
77#ifdef QT_GL_TEXTURE_GLYPH_CACHE_DEBUG
78 qDebug(" -> QGLGlyphTexture() %p for context %p.", this, ctx);
79#endif
80 }
81
82 void freeResource(QOpenGLContext *context) override
83 {
84 const QGLContext *ctx = QGLContext::fromOpenGLContext(platformContext: context);
85#ifdef QT_GL_TEXTURE_GLYPH_CACHE_DEBUG
86 qDebug("~QGLGlyphTexture() %p for context %p.", this, ctx);
87#else
88 Q_UNUSED(ctx);
89#endif
90 if (ctx && m_fbo)
91 ctx->contextHandle()->functions()->glDeleteFramebuffers(n: 1, framebuffers: &m_fbo);
92 if (m_width || m_height)
93 ctx->contextHandle()->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_OPENGL_EXPORT QGLTextureGlyphCache : public QImageTextureGlyphCache
111{
112public:
113 QGLTextureGlyphCache(QFontEngine::GlyphFormat format, const QTransform &matrix);
114 ~QGLTextureGlyphCache();
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 QGLTextureGlyphCache *that = const_cast<QGLTextureGlyphCache *>(this);
125 QGLGlyphTexture *glyphTexture = that->m_textureResource;
126 return glyphTexture ? glyphTexture->m_texture : 0;
127 }
128
129 inline int width() const {
130 QGLTextureGlyphCache *that = const_cast<QGLTextureGlyphCache *>(this);
131 QGLGlyphTexture *glyphTexture = that->m_textureResource;
132 return glyphTexture ? glyphTexture->m_width : 0;
133 }
134 inline int height() const {
135 QGLTextureGlyphCache *that = const_cast<QGLTextureGlyphCache *>(this);
136 QGLGlyphTexture *glyphTexture = that->m_textureResource;
137 return glyphTexture ? glyphTexture->m_height : 0;
138 }
139
140 inline void setPaintEnginePrivate(QGL2PaintEngineExPrivate *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
155private:
156 QGLGlyphTexture *m_textureResource;
157
158 QGL2PaintEngineExPrivate *pex;
159 QGLShaderProgram *m_blitProgram;
160 FilterMode m_filterMode;
161
162 GLfloat m_vertexCoordinateArray[8];
163 GLfloat m_textureCoordinateArray[8];
164
165 int m_serialNumber;
166};
167
168QT_END_NAMESPACE
169
170#endif
171
172

source code of qtbase/src/opengl/gl2paintengineex/qtextureglyphcache_gl_p.h