source: trunk/src/opengl/gl2paintengineex/qtextureglyphcache_gl_p.h

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#ifndef QTEXTUREGLYPHCACHE_GL_P_H
#define QTEXTUREGLYPHCACHE_GL_P_H

//
//  W A R N I N G
//  -------------
//
// This file is not part of the Qt API.  It exists for the convenience
// of the QLibrary class.  This header file may change from
// version to version without notice, or even be removed.
//
// We mean it.
//

#include <private/qtextureglyphcache_p.h>
#include <private/qgl_p.h>
#include <qglshaderprogram.h>


QT_BEGIN_NAMESPACE

class QGL2PaintEngineExPrivate;

class Q_OPENGL_EXPORT QGLTextureGlyphCache : public QObject, public QImageTextureGlyphCache
{
    Q_OBJECT
public:
    QGLTextureGlyphCache(QGLContext *context, QFontEngineGlyphCache::Type type, const QTransform &matrix);
    ~QGLTextureGlyphCache();

    virtual void createTextureData(int width, int height);
    virtual void resizeTextureData(int width, int height);
    virtual void fillTexture(const Coord &c, glyph_t glyph);
    virtual int glyphPadding() const;
    virtual int maxTextureWidth() const;
    virtual int maxTextureHeight() const;

    inline GLuint texture() const { return m_texture; }

    inline int width() const { return m_width; }
    inline int height() const { return m_height; }

    inline void setPaintEnginePrivate(QGL2PaintEngineExPrivate *p) { pex = p; }

    enum FilterMode {
        Nearest,
        Linear
    };
    FilterMode filterMode() const { return m_filterMode; }
    void setFilterMode(FilterMode m) { m_filterMode = m; }

    void setContext(QGLContext *context);
    QGLContext *context() const { return ctx; }

public Q_SLOTS:
    void contextDestroyed(const QGLContext *context) {
        if (context == ctx) {
            const QGLContext *nextCtx = qt_gl_transfer_context(ctx);
            if (!nextCtx) {
                // the context may not be current, so we cannot directly
                // destroy the fbo and texture here, but since the context
                // is about to be destroyed, the GL server will do the
                // clean up for us anyway. We reset everything, so that the
                // glyph cache object can be reused later by setting a new
                // context on it.
                m_fbo = 0;
                m_texture = 0;
                ctx = 0;
                m_width = 0;
                m_height = 0;
                m_w = 0;
                m_h = 0;
                m_cx = 0;
                m_cy = 0;
                m_currentRowHeight = 0;
                coords.clear();
            } else {
                // since the context holding the texture is shared, and
                // about to be destroyed, we have to transfer ownership
                // of the texture to one of the share contexts
                ctx = const_cast<QGLContext *>(nextCtx);
            }
        }
    }

    void clear();

private:
    QGLContext *ctx;

    QGL2PaintEngineExPrivate *pex;

    GLuint m_texture;
    GLuint m_fbo;

    int m_width;
    int m_height;

    QGLShaderProgram *m_program;

    FilterMode m_filterMode;
};

QT_END_NAMESPACE

#endif