QGLTexture Class Reference

#include <qgl_p.h>

Public Functions
	QGLTexture (QGLContext *ctx=0, GLuint tx_id=0, GLenum tx_target=GL_TEXTURE_2D, QGLContext::BindOptions opt=QGLContext::DefaultBindOption)
	~QGLTexture ()
bool	canBindCompressedTexture (const char *buf, int len, const char *format, bool *hasAlpha)
QSize	bindCompressedTexture (const QString &fileName, const char *format=0)
QSize	bindCompressedTexture (const char *buf, int len, const char *format=0)
QSize	bindCompressedTextureDDS (const char *buf, int len)
QSize	bindCompressedTexturePVR (const char *buf, int len)

Public Variables
QPixmapData *	boundPixmap
QGLContext *	context
GLuint	id
QGLContext::BindOptions	options
GLenum	target

Detailed Description

Definition at line 572 of file qgl_p.h.

Constructors and Destructors

QGLTexture()

QGLTexture::QGLTexture ( QGLContext *  ctx = 0, GLuint  tx_id = 0, GLenum  tx_target = GL_TEXTURE_2D, QGLContext::BindOptions  opt = QGLContext::DefaultBindOption  )

inline

Definition at line 574 of file qgl_p.h.

        : context(ctx),
          id(tx_id),
          target(tx_target),
          options(opt)
#if defined(Q_WS_X11)
        , boundPixmap(0)
#elif defined(Q_OS_SYMBIAN)
        , boundPixmap(0)
        , boundKey(0)
        , nextLRU(0)
        , prevLRU(0)
        , inLRU(false)
        , failedToAlloc(false)
        , inTexturePool(false)
#endif
    {}

~QGLTexture()

QGLTexture::~QGLTexture ( )

inline

Definition at line 593 of file qgl_p.h.

                  {
#ifdef Q_OS_SYMBIAN
        freeTexture();
#else
        if (options & QGLContext::MemoryManagedBindOption) {
            Q_ASSERT(context);
#if !defined(Q_WS_X11)
            QPixmapData *boundPixmap = 0;
#endif
            context->d_ptr->texture_destroyer->emitFreeTexture(context, boundPixmap, id);
        }
#endif
    }

Functions

bindCompressedTexture() [1/2]

QSize QGLTexture::bindCompressedTexture	(	const QString &	fileName,
		const char *	format = 0
	)

Definition at line 5996 of file qgl.cpp.

Referenced by QGLPixmapData::fromData(), and QGLPixmapData::fromFile().

{
    QFile file(fileName);
    if (!file.open(QIODevice::ReadOnly))
        return QSize();
    QByteArray contents = file.readAll();
    file.close();
    return bindCompressedTexture
        (contents.constData(), contents.size(), format);
}

bindCompressedTexture() [2/2]

QSize QGLTexture::bindCompressedTexture	(	const char *	buf,
		int	len,
		const char *	format = 0
	)

Definition at line 6097 of file qgl.cpp.

{
    if (QSysInfo::ByteOrder != QSysInfo::LittleEndian) {
        // Compressed texture loading only supported on little-endian
        // systems such as x86 and ARM at the moment.
        return QSize();
    }
#if !defined(QT_OPENGL_ES)
    if (!glCompressedTexImage2D) {
        if (!(QGLExtensions::glExtensions() & QGLExtensions::TextureCompression)) {
            qWarning("QGLContext::bindTexture(): The GL implementation does "
                     "not support texture compression extensions.");
            return QSize();
        }
        glCompressedTexImage2D = (_glCompressedTexImage2DARB) ctx->getProcAddress(QLatin1String("glCompressedTexImage2DARB"));
        if (!glCompressedTexImage2D) {
            qWarning("QGLContext::bindTexture(): could not resolve "
                     "glCompressedTexImage2DARB.");
            return QSize();
        }
    }
#endif
    if (!format) {
        // Auto-detect the format from the header.
        if (len >= 4 && !qstrncmp(buf, "DDS ", 4))
            return bindCompressedTextureDDS(buf, len);
        else if (len >= 52 && !qstrncmp(buf + 44, "PVR!", 4))
            return bindCompressedTexturePVR(buf, len);
    } else {
        // Validate the format against the header.
        if (!qstricmp(format, "DDS")) {
            if (len >= 4 && !qstrncmp(buf, "DDS ", 4))
                return bindCompressedTextureDDS(buf, len);
        } else if (!qstricmp(format, "PVR") || !qstricmp(format, "ETC1")) {
            if (len >= 52 && !qstrncmp(buf + 44, "PVR!", 4))
                return bindCompressedTexturePVR(buf, len);
        }
    }
    return QSize();
}

bindCompressedTextureDDS()

QSize QGLTexture::bindCompressedTextureDDS	(	const char *	buf,
		int	len
	)

Definition at line 6138 of file qgl.cpp.

{
    // We only support 2D texture loading at present.
    if (target != GL_TEXTURE_2D)
        return QSize();

    // Bail out if the necessary extension is not present.
    if (!(QGLExtensions::glExtensions() & QGLExtensions::DDSTextureCompression)) {
        qWarning("QGLContext::bindTexture(): DDS texture compression is not supported.");
        return QSize();
    }

    const DDSFormat *ddsHeader = reinterpret_cast<const DDSFormat *>(buf + 4);
    if (!ddsHeader->dwLinearSize) {
        qWarning("QGLContext::bindTexture(): DDS image size is not valid.");
        return QSize();
    }

    int blockSize = 16;
    GLenum format;

    switch(ddsHeader->ddsPixelFormat.dwFourCC) {
    case FOURCC_DXT1:
        format = GL_COMPRESSED_RGBA_S3TC_DXT1_EXT;
        blockSize = 8;
        break;
    case FOURCC_DXT3:
        format = GL_COMPRESSED_RGBA_S3TC_DXT3_EXT;
        break;
    case FOURCC_DXT5:
        format = GL_COMPRESSED_RGBA_S3TC_DXT5_EXT;
        break;
    default:
        qWarning("QGLContext::bindTexture(): DDS image format not supported.");
        return QSize();
    }

    const GLubyte *pixels =
        reinterpret_cast<const GLubyte *>(buf + ddsHeader->dwSize + 4);

    glGenTextures(1, &id);
    glBindTexture(GL_TEXTURE_2D, id);
    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);

    int size;
    int offset = 0;
    int available = len - int(ddsHeader->dwSize + 4);
    int w = ddsHeader->dwWidth;
    int h = ddsHeader->dwHeight;

    // load mip-maps
    for(int i = 0; i < (int) ddsHeader->dwMipMapCount; ++i) {
        if (w == 0) w = 1;
        if (h == 0) h = 1;

        size = ((w+3)/4) * ((h+3)/4) * blockSize;
        if (size > available)
            break;
        glCompressedTexImage2D(GL_TEXTURE_2D, i, format, w, h, 0,
                               size, pixels + offset);
        offset += size;
        available -= size;

        // half size for each mip-map level
        w = w/2;
        h = h/2;
    }

    // DDS images are not inverted.
    options &= ~QGLContext::InvertedYBindOption;

    return QSize(ddsHeader->dwWidth, ddsHeader->dwHeight);
}

bindCompressedTexturePVR()

QSize QGLTexture::bindCompressedTexturePVR	(	const char *	buf,
		int	len
	)

Definition at line 6213 of file qgl.cpp.

{
    // We only support 2D texture loading at present.  Cube maps later.
    if (target != GL_TEXTURE_2D)
        return QSize();

    // Determine which texture format we will be loading.
    const PvrHeader *pvrHeader = reinterpret_cast<const PvrHeader *>(buf);
    GLenum textureFormat;
    quint32 minWidth, minHeight;
    switch (pvrHeader->flags & PVR_FORMAT_MASK) {
    case PVR_FORMAT_PVRTC2:
        if (pvrHeader->alphaMask)
            textureFormat = GL_COMPRESSED_RGBA_PVRTC_2BPPV1_IMG;
        else
            textureFormat = GL_COMPRESSED_RGB_PVRTC_2BPPV1_IMG;
        minWidth = 16;
        minHeight = 8;
        break;

    case PVR_FORMAT_PVRTC4:
        if (pvrHeader->alphaMask)
            textureFormat = GL_COMPRESSED_RGBA_PVRTC_4BPPV1_IMG;
        else
            textureFormat = GL_COMPRESSED_RGB_PVRTC_4BPPV1_IMG;
        minWidth = 8;
        minHeight = 8;
        break;

    case PVR_FORMAT_ETC1:
        textureFormat = GL_ETC1_RGB8_OES;
        minWidth = 4;
        minHeight = 4;
        break;

    default:
        qWarning("QGLContext::bindTexture(): PVR image format 0x%x not supported.", int(pvrHeader->flags & PVR_FORMAT_MASK));
        return QSize();
    }

    // Bail out if the necessary extension is not present.
    if (textureFormat == GL_ETC1_RGB8_OES) {
        if (!(QGLExtensions::glExtensions() &
                    QGLExtensions::ETC1TextureCompression)) {
            qWarning("QGLContext::bindTexture(): ETC1 texture compression is not supported.");
            return QSize();
        }
    } else {
        if (!(QGLExtensions::glExtensions() &
                    QGLExtensions::PVRTCTextureCompression)) {
            qWarning("QGLContext::bindTexture(): PVRTC texture compression is not supported.");
            return QSize();
        }
    }

    // Boundary check on the buffer size.
    quint32 bufferSize = pvrHeader->headerSize + pvrHeader->dataSize;
    if (bufferSize > quint32(len)) {
        qWarning("QGLContext::bindTexture(): PVR image size is not valid.");
        return QSize();
    }

    // Create the texture.
    glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
    glGenTextures(1, &id);
    glBindTexture(GL_TEXTURE_2D, id);
    if (pvrHeader->mipMapCount) {
        if ((options & QGLContext::LinearFilteringBindOption) != 0) {
            glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
            glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
        } else {
            glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
            glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST_MIPMAP_NEAREST);
        }
    } else if ((options & QGLContext::LinearFilteringBindOption) != 0) {
        glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
        glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
    } else {
        glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
        glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
    }

    // Load the compressed mipmap levels.
    const GLubyte *buffer =
        reinterpret_cast<const GLubyte *>(buf + pvrHeader->headerSize);
    bufferSize = pvrHeader->dataSize;
    quint32 level = 0;
    quint32 width = pvrHeader->width;
    quint32 height = pvrHeader->height;
    while (bufferSize > 0 && level <= pvrHeader->mipMapCount) {
        quint32 size =
            (qMax(width, minWidth) * qMax(height, minHeight) *
             pvrHeader->bitsPerPixel) / 8;
        if (size > bufferSize)
            break;
        glCompressedTexImage2D(GL_TEXTURE_2D, GLint(level), textureFormat,
                               GLsizei(width), GLsizei(height), 0,
                               GLsizei(size), buffer);
        width /= 2;
        height /= 2;
        buffer += size;
        ++level;
    }

    // Restore the default pixel alignment for later texture uploads.
    glPixelStorei(GL_UNPACK_ALIGNMENT, 4);

    // Set the invert flag for the texture.  The "vertical flip"
    // flag in PVR is the opposite sense to our sense of inversion.
    if ((pvrHeader->flags & PVR_VERTICAL_FLIP) != 0)
        options &= ~QGLContext::InvertedYBindOption;
    else
        options |= QGLContext::InvertedYBindOption;

    return QSize(pvrHeader->width, pvrHeader->height);
}

canBindCompressedTexture()

bool QGLTexture::canBindCompressedTexture	(	const char *	buf,
		int	len,
		const char *	format,
		bool *	hasAlpha
	)

Definition at line 6057 of file qgl.cpp.

Referenced by QGLPixmapData::fromData(), and QGLPixmapData::fromFile().

{
    if (QSysInfo::ByteOrder != QSysInfo::LittleEndian) {
        // Compressed texture loading only supported on little-endian
        // systems such as x86 and ARM at the moment.
        return false;
    }
    if (!format) {
        // Auto-detect the format from the header.
        if (len >= 4 && !qstrncmp(buf, "DDS ", 4)) {
            *hasAlpha = true;
            return true;
        } else if (len >= 52 && !qstrncmp(buf + 44, "PVR!", 4)) {
            const PvrHeader *pvrHeader =
                reinterpret_cast<const PvrHeader *>(buf);
            *hasAlpha = (pvrHeader->alphaMask != 0);
            return true;
        }
    } else {
        // Validate the format against the header.
        if (!qstricmp(format, "DDS")) {
            if (len >= 4 && !qstrncmp(buf, "DDS ", 4)) {
                *hasAlpha = true;
                return true;
            }
        } else if (!qstricmp(format, "PVR") || !qstricmp(format, "ETC1")) {
            if (len >= 52 && !qstrncmp(buf + 44, "PVR!", 4)) {
                const PvrHeader *pvrHeader =
                    reinterpret_cast<const PvrHeader *>(buf);
                *hasAlpha = (pvrHeader->alphaMask != 0);
                return true;
            }
        }
    }
    return false;
}

Properties

boundPixmap

QPixmapData* QGLTexture::boundPixmap

Definition at line 614 of file qgl_p.h.

Referenced by QGLTexturePool::hibernate(), and QGLTexturePool::reclaimSpace().

context

QGLContext* QGLTexture::context

Definition at line 607 of file qgl_p.h.

id

GLuint QGLTexture::id

Definition at line 608 of file qgl_p.h.

Referenced by QGLPixmapData::bind(), QGLPixmapData::copy(), QGLPixmapData::copyBackFromRenderFbo(), QGLPixmapData::createPixmapForImage(), QGL2PaintEngineEx::drawImage(), QGL2PaintEngineEx::drawPixmap(), QGL2PaintEngineExPrivate::drawPixmapFragments(), QGLPixmapData::ensureCreated(), QGLPixmapData::fill(), QMeeGoPixmapData::fromTexture(), QMeeGoLivePixmapData::initializeThroughEGLImage(), QGLPixmapData::resize(), QGLPixmapData::toImage(), and QGLPixmapData::~QGLPixmapData().

options

QGLContext::BindOptions QGLTexture::options

Definition at line 611 of file qgl_p.h.

Referenced by QGLContextPrivate::bindTextureFromNativePixmap(), QGL2PaintEngineEx::drawPixmap(), QGL2PaintEngineExPrivate::drawPixmapFragments(), QOpenGLPaintEngine::drawTextureRect(), QOpenGLPaintEngine::drawTiledPixmap(), QGLPixmapData::ensureCreated(), QMeeGoPixmapData::fromEGLSharedImage(), QMeeGoLivePixmapData::initializeThroughEGLImage(), and QGL2PaintEngineExPrivate::updateBrushTexture().

target

GLenum QGLTexture::target

Definition at line 609 of file qgl_p.h.

---

The documentation for this class was generated from the following files:

• /src/opengl/qgl_p.h
• /src/opengl/qgl.cpp