StelTexture.hpp

/*
 * Stellarium
 * Copyright (C) 2006 Fabien Chereau
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA  02110-1335, USA.
 */

#ifndef _STELTEXTURE_HPP_
#define _STELTEXTURE_HPP_

#include "StelTextureTypes.hpp"
#include "StelOpenGL.hpp"

#include <QObject>
#include <QImage>

class QFile;
class StelTextureMgr;
class QNetworkReply;
template <class T> class QFuture;

#ifndef GL_CLAMP_TO_EDGE
#define GL_CLAMP_TO_EDGE 0x812F
#endif

class StelTexture: public QObject, public QEnableSharedFromThis<StelTexture>
{
    Q_OBJECT

public:
    struct StelTextureParams
    {
        StelTextureParams(bool qgenerateMipmaps=false, GLint afiltering=GL_LINEAR, GLint awrapMode=GL_CLAMP_TO_EDGE, bool qfilterMipmaps=false) :
                generateMipmaps(qgenerateMipmaps),
                filterMipmaps(qfilterMipmaps),
                filtering(afiltering),
                wrapMode(awrapMode){;}
        bool generateMipmaps;
        bool filterMipmaps;
        GLint filtering;
        GLint wrapMode;
    };

    virtual ~StelTexture();

    bool bind(int slot=0);

    inline void release() const { gl->glBindTexture(GL_TEXTURE_2D, 0 ); }

    void waitForLoaded();

    bool canBind() const {return id!=0;}

    bool getDimensions(int &width, int &height);

    bool hasAlphaChannel() const { return alphaChannel ; }

    const QString& getErrorMessage() const {return errorMessage;}

    bool hasError() const { return errorOccured; }

    const QString& getFullPath() const {return fullPath;}

    bool isLoading() const {return (loader || networkReply) && !canBind();}

    unsigned int getGlSize() const {return glSize;}

signals:
    void loadingProcessFinished(bool error);

private slots:
    void onNetworkReply();

private:
    friend class StelTextureMgr;

    struct GLData
    {
        GLData() : width(0), height(0), format(0), type(0) {}
        QString loaderError; 
        QByteArray data;
        int width;
        int height;
        GLint format;
        GLint type;
    };
    static GLData imageToGLData(const QImage &image);
    static GLData loadFromPath(const QString &path);
    static GLData loadFromData(const QByteArray& data);

    StelTexture(StelTextureMgr* mgr);

    void wrapGLTexture(GLuint texId);

    static QByteArray convertToGLFormat(const QImage& image, GLint* format, GLint* type);

    void reportError(const QString& errorMessage);

    bool glLoad(const QImage& image);
    bool glLoad(const GLData& data);

    bool load();

    template <typename T, typename Param1, typename Arg1>
    void startAsyncLoader(T (*functionPointer)(Param1), const Arg1 &arg1);

    StelTextureMgr* textureMgr;

    QOpenGLFunctions* gl;
    StelTextureParams loadParams;

    QNetworkReply *networkReply;

    QFuture<GLData>* loader;

    QString fullPath;

    bool errorOccured;

    bool alphaChannel;

    QString errorMessage;

    GLuint id;

    GLsizei width;  
    GLsizei height; 

    unsigned int glSize;
};


#endif // _STELTEXTURE_HPP_