source: trunk/src/opengl/qglpixelbuffer_egl.cpp@ 385

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#include <qdebug.h>
#include "qglpixelbuffer.h"
#include "qglpixelbuffer_p.h"
#include "qgl_egl_p.h"

#include <qimage.h>
#include <private/qgl_p.h>

QT_BEGIN_NAMESPACE

#ifdef EGL_BIND_TO_TEXTURE_RGBA
#define QGL_RENDER_TEXTURE 1
#else
#define QGL_RENDER_TEXTURE 0
#endif

bool QGLPixelBufferPrivate::init(const QSize &size, const QGLFormat &f, QGLWidget *shareWidget)
{
    // Create the EGL context.
    ctx = new QEglContext();
    ctx->setApi(QEglContext::OpenGL);

    // Open the EGL display.
    if (!ctx->openDisplay(0)) {
        delete ctx;
        ctx = 0;
        return false;
    }

    // Choose an appropriate configuration.  We use the best format
    // we can find, even if it is greater than the requested format.
    // We try for a pbuffer that is capable of texture rendering if possible.
    QEglProperties configProps;
    qt_egl_set_format(configProps, QInternal::Pbuffer, f);
    configProps.setRenderableType(ctx->api());
    bool ok = false;
#if QGL_RENDER_TEXTURE
    textureFormat = EGL_TEXTURE_RGBA;
    configProps.setValue(EGL_BIND_TO_TEXTURE_RGBA, EGL_TRUE);
    ok = ctx->chooseConfig(configProps, QEglContext::BestPixelFormat);
    if (!ok) {
        // Try again with RGB texture rendering.
        textureFormat = EGL_TEXTURE_RGB;
        configProps.removeValue(EGL_BIND_TO_TEXTURE_RGBA);
        configProps.setValue(EGL_BIND_TO_TEXTURE_RGB, EGL_TRUE);
        ok = ctx->chooseConfig(configProps, QEglContext::BestPixelFormat);
        if (!ok) {
            // One last try for a pbuffer with no texture rendering.
            configProps.removeValue(EGL_BIND_TO_TEXTURE_RGB);
            textureFormat = EGL_NONE;
        }
    }
#else
    textureFormat = EGL_NONE;
#endif
    if (!ok) {
        if (!ctx->chooseConfig(configProps, QEglContext::BestPixelFormat)) {
            delete ctx;
            ctx = 0;
            return false;
        }
    }

    // Retrieve the actual format properties.
    qt_egl_update_format(*ctx, format);

    // Create the attributes needed for the pbuffer.
    QEglProperties attribs;
    attribs.setValue(EGL_WIDTH, size.width());
    attribs.setValue(EGL_HEIGHT, size.height());
#if QGL_RENDER_TEXTURE
    if (textureFormat != EGL_NONE) {
        attribs.setValue(EGL_TEXTURE_FORMAT, textureFormat);
        attribs.setValue(EGL_TEXTURE_TARGET, EGL_TEXTURE_2D);
    }
#endif