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

#include <qlibrary.h>

#include <qdebug.h>

#include <private/qgl_p.h>

#include <private/qt_x11_p.h>

#include <private/qpaintengine_opengl_p.h>

#include <qx11info_x11.h>

#include <GL/glx.h>

#include <qimage.h>

#include "qglpixelbuffer.h"

#include "qglpixelbuffer_p.h"

#if defined(Q_OS_LINUX) || defined(Q_OS_BSD4)

#include <dlfcn.h>

#endif

QT_BEGIN_NAMESPACE

#ifndef GLX_VERSION_1_3

#define GLX_RGBA_BIT            0x00000002

#define GLX_PBUFFER_BIT         0x00000004

#define GLX_DRAWABLE_TYPE       0x8010

#define GLX_RENDER_TYPE         0x8011

#define GLX_RGBA_TYPE           0x8014

#define GLX_PBUFFER_HEIGHT      0x8040

#define GLX_PBUFFER_WIDTH       0x8041

#endif

#ifndef GLX_ARB_multisample

#define GLX_SAMPLE_BUFFERS_ARB  100000

#define GLX_SAMPLES_ARB         100001

#endif

typedef GLXFBConfig* (*_glXChooseFBConfig) (Display *dpy, int screen, const int *attrib_list, int *nelements);

typedef int (*_glXGetFBConfigAttrib) (Display *dpy, GLXFBConfig config, int attribute, int *value);

typedef GLXPbuffer (*_glXCreatePbuffer) (Display *dpy, GLXFBConfig config, const int *attrib_list);

typedef void (*_glXDestroyPbuffer) (Display *dpy, GLXPbuffer pbuf);

typedef GLXContext (*_glXCreateNewContext) (Display *dpy, GLXFBConfig config, int render_type, GLXContext share_list, Bool direct);

typedef Bool (*_glXMakeContextCurrent) (Display *dpy, GLXDrawable draw, GLXDrawable read, GLXContext ctx);

static _glXChooseFBConfig qt_glXChooseFBConfig = 0;

static _glXCreateNewContext qt_glXCreateNewContext = 0;

static _glXCreatePbuffer qt_glXCreatePbuffer = 0;

static _glXDestroyPbuffer qt_glXDestroyPbuffer = 0;

static _glXGetFBConfigAttrib qt_glXGetFBConfigAttrib = 0;

static _glXMakeContextCurrent qt_glXMakeContextCurrent = 0;

#define glXChooseFBConfig qt_glXChooseFBConfig

#define glXCreateNewContext qt_glXCreateNewContext

#define glXCreatePbuffer qt_glXCreatePbuffer

#define glXDestroyPbuffer qt_glXDestroyPbuffer

#define glXGetFBConfigAttrib qt_glXGetFBConfigAttrib

#define glXMakeContextCurrent qt_glXMakeContextCurrent

extern void* qglx_getProcAddress(const char* procName); // in qgl_x11.cpp

static bool qt_resolve_pbuffer_extensions()

{

    static int resolved = false;

    if (resolved && qt_glXMakeContextCurrent)

        return true;

    else if (resolved)

        return false;

    qt_glXChooseFBConfig = (_glXChooseFBConfig) qglx_getProcAddress("glXChooseFBConfig");

    qt_glXCreateNewContext = (_glXCreateNewContext) qglx_getProcAddress("glXCreateNewContext");

    qt_glXCreatePbuffer = (_glXCreatePbuffer) qglx_getProcAddress("glXCreatePbuffer");

    qt_glXDestroyPbuffer = (_glXDestroyPbuffer) qglx_getProcAddress("glXDestroyPbuffer");

    qt_glXGetFBConfigAttrib = (_glXGetFBConfigAttrib) qglx_getProcAddress("glXGetFBConfigAttrib");

    qt_glXMakeContextCurrent = (_glXMakeContextCurrent) qglx_getProcAddress("glXMakeContextCurrent");

    resolved = qt_glXMakeContextCurrent ? true : false;

    return resolved;

}

static void qt_format_to_attrib_list(const QGLFormat &f, int attribs[])

{

    int i = 0;

    attribs[i++] = GLX_RENDER_TYPE;

    attribs[i++] = GLX_RGBA_BIT;

    attribs[i++] = GLX_DRAWABLE_TYPE;

    attribs[i++] = GLX_PBUFFER_BIT;

    attribs[i++] = GLX_RED_SIZE;

    attribs[i++] = f.redBufferSize() == -1 ? 1 : f.redBufferSize();

    attribs[i++] = GLX_GREEN_SIZE;

    attribs[i++] = f.greenBufferSize() == -1 ? 1 : f.greenBufferSize();

    attribs[i++] = GLX_BLUE_SIZE;

    attribs[i++] = f.blueBufferSize() == -1 ? 1 : f.blueBufferSize();

    if (f.doubleBuffer()) {

        attribs[i++] = GLX_DOUBLEBUFFER;

        attribs[i++] = true;

    }

    if (f.depth()) {

        attribs[i++] = GLX_DEPTH_SIZE;

        attribs[i++] = f.depthBufferSize() == -1 ? 1 : f.depthBufferSize();

    }

    if (f.stereo()) {

        attribs[i++] = GLX_STEREO;

        attribs[i++] = true;

    }

    if (f.stencil()) {

        attribs[i++] = GLX_STENCIL_SIZE;

        attribs[i++] = f.stencilBufferSize() == -1 ? 1 : f.stencilBufferSize();

    }

    if (f.alpha()) {

        attribs[i++] = GLX_ALPHA_SIZE;

        attribs[i++] = f.alphaBufferSize() == -1 ? 1 : f.alphaBufferSize();

    }

    if (f.accum()) {

        attribs[i++] = GLX_ACCUM_RED_SIZE;

        attribs[i++] = f.accumBufferSize() == -1 ? 1 : f.accumBufferSize();

        attribs[i++] = GLX_ACCUM_GREEN_SIZE;

        attribs[i++] = f.accumBufferSize() == -1 ? 1 : f.accumBufferSize();

        attribs[i++] = GLX_ACCUM_BLUE_SIZE;

        attribs[i++] = f.accumBufferSize() == -1 ? 1 : f.accumBufferSize();

        if (f.alpha()) {

            attribs[i++] = GLX_ACCUM_ALPHA_SIZE;

            attribs[i++] = f.accumBufferSize() == -1 ? 1 : f.accumBufferSize();

        }

    }

    if (f.sampleBuffers()) {

        attribs[i++] = GLX_SAMPLE_BUFFERS_ARB;

        attribs[i++] = 1;

        attribs[i++] = GLX_SAMPLES_ARB;

        attribs[i++] = f.samples() == -1 ? 4 : f.samples();

    }

    attribs[i] = XNone;

}

bool QGLPixelBufferPrivate::init(const QSize &size, const QGLFormat &f, QGLWidget *shareWidget)

{

    if (!qt_resolve_pbuffer_extensions()) {

        qWarning("QGLPixelBuffer: pbuffers are not supported on this system.");

        return false;

    }

    int attribs[40];

    int num_configs = 0;

    qt_format_to_attrib_list(f, attribs);

    GLXFBConfig *configs = glXChooseFBConfig(X11->display, X11->defaultScreen, attribs, &num_configs);

    if (configs && num_configs) {

        int res;

        glXGetFBConfigAttrib(X11->display, configs[0], GLX_LEVEL, &res);

        format.setPlane(res);

        glXGetFBConfigAttrib(X11->display, configs[0], GLX_DOUBLEBUFFER, &res);

        format.setDoubleBuffer(res);

        glXGetFBConfigAttrib(X11->display, configs[0], GLX_DEPTH_SIZE, &res);

        format.setDepth(res);

        if (format.depth())

            format.setDepthBufferSize(res);

        glXGetFBConfigAttrib(X11->display, configs[0], GLX_RGBA, &res);

        format.setRgba(res);

        glXGetFBConfigAttrib(X11->display, configs[0], GLX_RED_SIZE, &res);

        format.setRedBufferSize(res);

        glXGetFBConfigAttrib(X11->display, configs[0], GLX_GREEN_SIZE, &res);

        format.setGreenBufferSize(res);

        glXGetFBConfigAttrib(X11->display, configs[0], GLX_BLUE_SIZE, &res);

        format.setBlueBufferSize(res);

        glXGetFBConfigAttrib(X11->display, configs[0], GLX_ALPHA_SIZE, &res);

        format.setAlpha(res);

        if (format.alpha())

            format.setAlphaBufferSize(res);

        glXGetFBConfigAttrib(X11->display, configs[0], GLX_ACCUM_RED_SIZE, &res);

        format.setAccum(res);

        if (format.accum())

            format.setAccumBufferSize(res);

        glXGetFBConfigAttrib(X11->display, configs[0], GLX_STENCIL_SIZE, &res);

        format.setStencil(res);

        if (format.stencil())

            format.setStencilBufferSize(res);

        glXGetFBConfigAttrib(X11->display, configs[0], GLX_STEREO, &res);

        format.setStereo(res);

        glXGetFBConfigAttrib(X11->display, configs[0], GLX_SAMPLE_BUFFERS_ARB, &res);

        format.setSampleBuffers(res);

        if (format.sampleBuffers()) {

            glXGetFBConfigAttrib(X11->display, configs[0], GLX_SAMPLES_ARB, &res);

            format.setSamples(res);

        }

        int pb_attribs[] = {GLX_PBUFFER_WIDTH, size.width(), GLX_PBUFFER_HEIGHT, size.height(), XNone};

        GLXContext shareContext = 0;

        if (shareWidget && shareWidget->d_func()->glcx)

            shareContext = (GLXContext) shareWidget->d_func()->glcx->d_func()->cx;

        pbuf = glXCreatePbuffer(QX11Info::display(), configs[0], pb_attribs);

        ctx = glXCreateNewContext(QX11Info::display(), configs[0], GLX_RGBA_TYPE, shareContext, true);

        XFree(configs);

        if (!pbuf || !ctx) {

            qWarning("QGLPixelBuffer: Unable to create a pbuffer/context - giving up.");

            return false;

        }

        return true;

    } else {

        qWarning("QGLPixelBuffer: Unable to find a context/format match - giving up.");

        return false;

    }

}

bool QGLPixelBufferPrivate::cleanup()

{

    glXDestroyPbuffer(QX11Info::display(), pbuf);

    return true;

}

bool QGLPixelBuffer::bindToDynamicTexture(GLuint)

{

    return false;

}

void QGLPixelBuffer::releaseFromDynamicTexture()

{

}

bool QGLPixelBuffer::hasOpenGLPbuffers()

{

    bool ret = qt_resolve_pbuffer_extensions();

    if (!ret)

	return false;

    int attribs[40];

    int num_configs = 0;

    qt_format_to_attrib_list(QGLFormat::defaultFormat(), attribs);

    GLXFBConfig *configs = glXChooseFBConfig(X11->display, X11->defaultScreen, attribs, &num_configs);

    GLXPbuffer pbuf = 0;

    GLXContext ctx = 0;

    if (configs && num_configs) {

        int pb_attribs[] = {GLX_PBUFFER_WIDTH, 128, GLX_PBUFFER_HEIGHT, 128, XNone};

        pbuf = glXCreatePbuffer(X11->display, configs[0], pb_attribs);

        ctx = glXCreateNewContext(X11->display, configs[0], GLX_RGBA_TYPE, 0, true);

        XFree(configs);

	glXDestroyContext(X11->display, ctx);

	glXDestroyPbuffer(X11->display, pbuf);

    }

    return pbuf && ctx;

}

QT_END_NAMESPACE