Displaying flipped StaticImage.
Posted: Wed Oct 09, 2013 11:05
Hello All,
My post is related to CEGUI 0.7.7.
Don't know if this is a frequent problem, but in our project we need to display some pictures with opposite orientation (it's a game battle screen with character icons at the left and mirrored icons at the right). So I used CEGUI layout containing StaticImage's with
It worked fine, but with full set of icons I noticed memory consumption, because, as I understand, CEGUI creates new render-to-texture for each window with "Rotation" property. Moreover, texture dimensions are set to the nearest higher power-of-two, i.e. for the 600x600 pixels window it creates 1024x1024 texture.
To avoid this consumption I wrote a routine, which sets a rotation directly to the window GeometryBuffer, something like this:
Of course, it's not a full replacement for the "Rotation" property, because it rotates only an image, not a whole window contents. Also maybe there is a simplier way to manipulate images in latter versions of CEGUI.
Is it correct to do so? Now I'm in doubt, because I read "the content of that(GeometryBuffer) is reset when CEGUI decides that a redraw is needed" on this forum.
My post is related to CEGUI 0.7.7.
Don't know if this is a frequent problem, but in our project we need to display some pictures with opposite orientation (it's a game battle screen with character icons at the left and mirrored icons at the right). So I used CEGUI layout containing StaticImage's with
Code: Select all
<Property Name="Rotation" Value="x:0 y:180 z:0" />
It worked fine, but with full set of icons I noticed memory consumption, because, as I understand, CEGUI creates new render-to-texture for each window with "Rotation" property. Moreover, texture dimensions are set to the nearest higher power-of-two, i.e. for the 600x600 pixels window it creates 1024x1024 texture.
To avoid this consumption I wrote a routine, which sets a rotation directly to the window GeometryBuffer, something like this:
Code: Select all
void MainMenuWindow::SetStaticImageHorizontalFlip(CEGUI::Window *win, bool flip) {
// Here we determine names of ImageSet and Image of the StaticImage.
// I use Ogre::StringUtils to parse strings, you can use any other string-processing library.
std::string set_name, image_name;
std::string s = win->getProperty("Image").c_str();
Ogre::StringVector params;
params = Ogre::StringUtil::split(s, " ");
Ogre::StringVector subparams;
subparams = Ogre::StringUtil::split(params[0], ":");
if (subparams[0] == "set") set_name = subparams[1];
else if (subparams[0] == "image") image_name = subparams[1];
subparams = Ogre::StringUtil::split(params[1], ":");
if (subparams[0] == "set") set_name = subparams[1];
else if (subparams[0] == "image") image_name = subparams[1];
// Determine image width (we need it to perform correct transformation).
CEGUI::Imageset& imageset = CEGUI::ImagesetManager::getSingleton().get(set_name);
// Why it returns HALF a width?..
float width = imageset.getImageWidth(image_name) * 2;
// Move pivot to the right, so the image will not go out of clipping area after rotation.
win->getGeometryBuffer().setPivot(CEGUI::Vector3(width, 0.0f, 0.0f));
// Horizontal flipping is equivalent to 180-degree rotation around Y.
float angle = flip ? 180.0f : 0.0f;
// Vector components represent rotation angles in degrees around corresponding axes.
win->getGeometryBuffer().setRotation(CEGUI::Vector3(0.0f, angle, 0.0f));
}
Of course, it's not a full replacement for the "Rotation" property, because it rotates only an image, not a whole window contents. Also maybe there is a simplier way to manipulate images in latter versions of CEGUI.
Is it correct to do so? Now I'm in doubt, because I read "the content of that(GeometryBuffer) is reset when CEGUI decides that a redraw is needed" on this forum.