Q_GUI_EXPORT QImage qt_gl_read_framebuffer(const QSize &size, bool alpha_format, bool include_alpha)
{
int w = size.width();
int h = size.height();
QOpenGLFunctions *funcs = QOpenGLContext::currentContext()->functions();
while (funcs->glGetError());
#if Q_BYTE_ORDER == Q_LITTLE_ENDIAN
QImage img(size, (alpha_format && include_alpha) ? QImage::Format_ARGB32_Premultiplied
: QImage::Format_RGB32);
#ifdef QT_OPENGL_ES
GLint fmt = GL_BGRA_EXT;
#else
GLint fmt = GL_BGRA;
#endif
funcs->glReadPixels(0, 0, w, h, fmt, GL_UNSIGNED_BYTE, img.bits());
if (!funcs->glGetError())
return img.mirrored();
#endif
QImage rgbaImage(size, (alpha_format && include_alpha) ? QImage::Format_RGBA8888_Premultiplied
: QImage::Format_RGBX8888);
funcs->glReadPixels(0, 0, w, h, GL_RGBA, GL_UNSIGNED_BYTE, rgbaImage.bits());
return rgbaImage.mirrored();
}
QImage gl_read_framebuffer(const QRect &rect) {
QSize size = rect.size();
int x = rect.x();
int y = rect.y();
while (glGetError());
QImage img(size, QImage::Format_RGB32);
GLint fmt = GL_BGRA_EXT;
glReadPixels(x, y, size.width(), size.height(), fmt, GL_UNSIGNED_BYTE, img.bits());
if (!glGetError())
return img.mirrored();
QImage rgbaImage(size, QImage::Format_RGBX8888);
glReadPixels(x, y, size.width(), size.height(), GL_RGBA, GL_UNSIGNED_BYTE, rgbaImage.bits());
return rgbaImage.mirrored();
}