Creates a IDOMFixedPage from an IPage, rotating content and cropbox as needed

applyPageRotation.cpp

// Create a IDOMFixedPage from an IPage, rotating content and cropbox as needed
static bool applyPageRotation(IJawsMakoPtr jawsMako, IPagePtr page, IDOMFixedPagePtr& fixedPage, FRect& cropBox)
{
    if (!page)
        return false;

    // Does the page have crop margins?
    // Note: page->getCropBox() will return the cropbox dimensions if set, or the mediabox (absolute page size) dimensions if not
    // A fixedPage() does not offer this guarantee, so fixedPage->getCropBox() may return an empty FRect() (ie one or more values < 0)
    cropBox = page->getCropBox();

    // Is the page rotated?
    const int32 rotationDegrees = (page->getRotate() + 360) % 360;

    // Create a fixed page from the page contents, editable if content is to be rotated
    fixedPage = rotationDegrees ? page->clone()->edit() : page->getContent();

    // Rotate content as required
    if (rotationDegrees)
    {
        const double width = fixedPage->getWidth();
        const double height = fixedPage->getHeight();

        FMatrix rotate;

        switch (rotationDegrees / 90)
        {
        case 1: // 90 degrees
            fixedPage->setWidth(height);
            fixedPage->setHeight(width);
            rotate.setDX(height);
            break;

        case 2: // 180 degrees
            rotate.setDX(width);
            rotate.setDY(height);
            break;

        case 3: // 270 degrees
            fixedPage->setWidth(height);
            fixedPage->setHeight(width);
            rotate.setDY(width);
            break;

        default:
            break;
        }

        rotate.rotate(rotationDegrees * PI / 180.0);

        // Extract page objects into a group with the transform matrix at its root 
        IDOMGroupPtr transformGroup = IDOMGroup::create(jawsMako, rotate);
        IDOMNodePtr node;
        while ((node = fixedPage->extractChild(IDOMNodePtr())) != nullptr)
            transformGroup->appendChild(node);

        // Add rotated objects to page
        fixedPage->appendChild(transformGroup);

        // Rotate cropbox
        rotate.transformRect(cropBox);
    }
    fixedPage->setCropBox(cropBox);

    return true;
}