/****************************************************************************

**

** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).

** All rights reserved.

** Contact: Nokia Corporation (qt-info@nokia.com)

**

** This file is part of the QtOpenGL module of the Qt Toolkit.

**

** $QT_BEGIN_LICENSE:LGPL$

** No Commercial Usage

** This file contains pre-release code and may not be distributed.

** You may use this file in accordance with the terms and conditions

** contained in the Technology Preview License Agreement accompanying

** this package.

**

** GNU Lesser General Public License Usage

** Alternatively, this file may be used under the terms of the GNU Lesser

** General Public License version 2.1 as published by the Free Software

** Foundation and appearing in the file LICENSE.LGPL included in the

** packaging of this file.  Please review the following information to

** ensure the GNU Lesser General Public License version 2.1 requirements

** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.

**

** In addition, as a special exception, Nokia gives you certain additional

** rights.  These rights are described in the Nokia Qt LGPL Exception

** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.

**

** If you have questions regarding the use of this file, please contact

** Nokia at qt-info@nokia.com.

**

**

**

**

**

**

**

**

** $QT_END_LICENSE$

**

****************************************************************************/

#ifndef QGRAPHICSCONTEXT_OPENGL2_P_H

#define QGRAPHICSCONTEXT_OPENGL2_P_H

//

//  W A R N I N G

//  -------------

//

// This file is not part of the Qt API.  It exists purely as an

// implementation detail.  This header file may change from version to

// version without notice, or even be removed.

//

// We mean it.

//

#include <QDebug>

#include <private/qpaintengineex_p.h>

#include <private/qglengineshadermanager_p.h>

#include <private/qgl2pexvertexarray_p.h>

#include <private/qglpaintdevice_p.h>

#include <private/qglpixmapfilter_p.h>

#include <private/qfontengine_p.h>

#include <private/qdatabuffer_p.h>

#include <private/qtriangulatingstroker_p.h>

enum EngineMode {

    ImageDrawingMode,

    TextDrawingMode,

    BrushDrawingMode,

    ImageArrayDrawingMode

};

QT_BEGIN_NAMESPACE

#define GL_STENCIL_HIGH_BIT         GLuint(0x80)

#define QT_BRUSH_TEXTURE_UNIT       GLuint(0)

#define QT_IMAGE_TEXTURE_UNIT       GLuint(0) //Can be the same as brush texture unit

#define QT_MASK_TEXTURE_UNIT        GLuint(1)

#define QT_BACKGROUND_TEXTURE_UNIT  GLuint(2)

class QGL2PaintEngineExPrivate;

class QOpenGL2PaintEngineState : public QPainterState

{

public:

    QOpenGL2PaintEngineState(QOpenGL2PaintEngineState &other);

    QOpenGL2PaintEngineState();

    ~QOpenGL2PaintEngineState();

    uint isNew : 1;

    uint needsClipBufferClear : 1;

    uint clipTestEnabled : 1;

    uint canRestoreClip : 1;

    uint matrixChanged : 1;

    uint compositionModeChanged : 1;

    uint opacityChanged : 1;

    uint renderHintsChanged : 1;

    uint clipChanged : 1;

    uint currentClip : 8;

    QRect rectangleClip;

};

class Q_OPENGL_EXPORT QGL2PaintEngineEx : public QPaintEngineEx

{

    Q_DECLARE_PRIVATE(QGL2PaintEngineEx)

public:

    QGL2PaintEngineEx();

    ~QGL2PaintEngineEx();

    bool begin(QPaintDevice *device);

    void ensureActive();

    bool end();

    virtual void clipEnabledChanged();

    virtual void penChanged();

    virtual void brushChanged();

    virtual void brushOriginChanged();

    virtual void opacityChanged();

    virtual void compositionModeChanged();

    virtual void renderHintsChanged();

    virtual void transformChanged();

    virtual void drawTexture(const QRectF &r, GLuint textureId, const QSize &size, const QRectF &sr);

    virtual void drawPixmap(const QRectF &r, const QPixmap &pm, const QRectF &sr);

    virtual void drawPixmaps(const QDrawPixmaps::Data *drawingData, int dataCount, const QPixmap &pixmap, QDrawPixmaps::DrawingHints hints);

    virtual void drawImage(const QRectF &r, const QImage &pm, const QRectF &sr,

                           Qt::ImageConversionFlags flags = Qt::AutoColor);

    virtual void drawTextItem(const QPointF &p, const QTextItem &textItem);

    virtual void fill(const QVectorPath &path, const QBrush &brush);

    virtual void stroke(const QVectorPath &path, const QPen &pen);

    virtual void clip(const QVectorPath &path, Qt::ClipOperation op);

    Type type() const { return OpenGL2; }

    virtual void setState(QPainterState *s);

    virtual QPainterState *createState(QPainterState *orig) const;

    inline QOpenGL2PaintEngineState *state() {

        return static_cast<QOpenGL2PaintEngineState *>(QPaintEngineEx::state());

    }

    inline const QOpenGL2PaintEngineState *state() const {

        return static_cast<const QOpenGL2PaintEngineState *>(QPaintEngineEx::state());

    }

    void beginNativePainting();

    void endNativePainting();

    QPixmapFilter *pixmapFilter(int type, const QPixmapFilter *prototype);

    void setRenderTextActive(bool);

private:

    Q_DISABLE_COPY(QGL2PaintEngineEx)

};

class QGL2PaintEngineExPrivate : public QPaintEngineExPrivate

{

    Q_DECLARE_PUBLIC(QGL2PaintEngineEx)

public:

    enum StencilFillMode {

        OddEvenFillMode,

        WindingFillMode,

        TriStripStrokeFillMode

    };

    QGL2PaintEngineExPrivate(QGL2PaintEngineEx *q_ptr) :

            q(q_ptr),

            shaderManager(0),

            width(0), height(0),

            ctx(0),

            useSystemClip(true),

            snapToPixelGrid(false),

            addOffset(false),

            inverseScale(1)

    { }

    ~QGL2PaintEngineExPrivate();

    void updateBrushTexture();

    void updateBrushUniforms();

    void updateMatrix();

    void updateCompositionMode();

    void updateTextureFilter(GLenum target, GLenum wrapMode, bool smoothPixmapTransform, GLuint id = -1);

    void resetGLState();

    // fill, stroke, drawTexture, drawPixmaps & drawCachedGlyphs are the main rendering entry-points,

    // however writeClip can also be thought of as en entry point as it does similar things.

    void fill(const QVectorPath &path);

    void stroke(const QVectorPath &path, const QPen &pen);

    void drawTexture(const QGLRect& dest, const QGLRect& src, const QSize &textureSize, bool opaque, bool pattern = false);

    void drawPixmaps(const QDrawPixmaps::Data *drawingData, int dataCount, const QPixmap &pixmap, QDrawPixmaps::DrawingHints hints);

    void drawCachedGlyphs(const QPointF &p, QFontEngineGlyphCache::Type glyphType, const QTextItemInt &ti);

    // Calls glVertexAttributePointer if the pointer has changed

    inline void setVertexAttributePointer(unsigned int arrayIndex, const GLfloat *pointer);

    // draws whatever is in the vertex array:

    void drawVertexArrays(const float *data, int *stops, int stopCount, GLenum primitive);

    void drawVertexArrays(QGL2PEXVertexArray &vertexArray, GLenum primitive) {

        drawVertexArrays((const float *) vertexArray.data(), vertexArray.stops(), vertexArray.stopCount(), primitive);

    }

    // Composites the bounding rect onto dest buffer:

    void composite(const QGLRect& boundingRect);

    // Calls drawVertexArrays to render into stencil buffer:

    void fillStencilWithVertexArray(const float *data, int count, int *stops, int stopCount, const QGLRect &bounds, StencilFillMode mode);

    void fillStencilWithVertexArray(QGL2PEXVertexArray& vertexArray, bool useWindingFill) {

        fillStencilWithVertexArray((const float *) vertexArray.data(), 0, vertexArray.stops(), vertexArray.stopCount(),

                                   vertexArray.boundingRect(),

                                   useWindingFill ? WindingFillMode : OddEvenFillMode);

    }

    void setBrush(const QBrush& brush);

    void transferMode(EngineMode newMode);

    bool prepareForDraw(bool srcPixelsAreOpaque); // returns true if the program has changed

    inline void useSimpleShader();

    inline GLuint location(const QGLEngineShaderManager::Uniform uniform) {

        return shaderManager->getUniformLocation(uniform);

    }

    void clearClip(uint value);

    void writeClip(const QVectorPath &path, uint value);

    void resetClipIfNeeded();

    void updateClipScissorTest();

    void setScissor(const QRect &rect);

    void regenerateClip();

    void systemStateChanged();

    static QGLEngineShaderManager* shaderManagerForEngine(QGL2PaintEngineEx *engine) { return engine->d_func()->shaderManager; }

    static QGL2PaintEngineExPrivate *getData(QGL2PaintEngineEx *engine) { return engine->d_func(); }

    static void cleanupVectorPath(QPaintEngineEx *engine, void *data);

    QGL2PaintEngineEx* q;

    QGLEngineShaderManager* shaderManager;

    QGLPaintDevice* device;

    int width, height;

    QGLContext *ctx;

    EngineMode mode;

    QFontEngineGlyphCache::Type glyphCacheType;

    // Dirty flags

    bool matrixDirty; // Implies matrix uniforms are also dirty

    bool compositionModeDirty;

    bool brushTextureDirty;

    bool brushUniformsDirty;

    bool opacityUniformDirty;

    bool stencilClean; // Has the stencil not been used for clipping so far?

    bool useSystemClip;

    QRegion dirtyStencilRegion;

    QRect currentScissorBounds;

    uint maxClip;

    QBrush currentBrush; // May not be the state's brush!

    const QBrush noBrush;

    QGL2PEXVertexArray vertexCoordinateArray;

    QGL2PEXVertexArray textureCoordinateArray;

    QDataBuffer<GLfloat> opacityArray;

    GLfloat staticVertexCoordinateArray[8];

    GLfloat staticTextureCoordinateArray[8];

    bool snapToPixelGrid;

    bool addOffset; // When enabled, adds a 0.49,0.49 offset to matrix in updateMatrix

    GLfloat pmvMatrix[3][3];

    GLfloat inverseScale;

    GLuint lastTextureUsed;

    bool needsSync;

    bool multisamplingAlwaysEnabled;

    GLfloat depthRange[2];

    float textureInvertedY;

    QTriangulatingStroker stroker;

    QDashedStrokeProcessor dasher;

    QScopedPointer<QPixmapFilter> convolutionFilter;

    QScopedPointer<QPixmapFilter> colorizeFilter;

    QScopedPointer<QPixmapFilter> blurFilter;

    QScopedPointer<QPixmapFilter> dropShadowFilter;

    QSet<QVectorPath::CacheEntry *> pathCaches;

    QVector<GLuint> unusedVBOSToClean;

    const GLfloat *vertexAttribPointers[3];

};

void QGL2PaintEngineExPrivate::setVertexAttributePointer(unsigned int arrayIndex, const GLfloat *pointer)

{

    Q_ASSERT(arrayIndex < 3);

    if (pointer == vertexAttribPointers[arrayIndex])

        return;

    vertexAttribPointers[arrayIndex] = pointer;

    if (arrayIndex == QT_OPACITY_ATTR)

        glVertexAttribPointer(arrayIndex, 1, GL_FLOAT, GL_FALSE, 0, pointer);

    else

        glVertexAttribPointer(arrayIndex, 2, GL_FLOAT, GL_FALSE, 0, pointer);

}

QT_END_NAMESPACE

#endif