bool
AtlasBuilder::build(const ResourceLibrary* inputLib,
const std::string& newAtlasURI,
Atlas& out ) const
{
if ( !inputLib )
return false;
// prepare an atlaser:
TextureAtlasBuilderEx tab;
// maximum size of the texture (x,y)
tab.setMaximumAtlasSize( (int)_width, (int)_height );
// texels between atlased images
tab.setMargin( 1 );
// clone the Resource library so we can re-write the URIs and add
// texture matrix information.
out._lib = new ResourceLibrary( inputLib->getConfig() );
out._lib->initialize( _options );
out._lib->uri().unset();
// store a mapping from atlasbuilder source to skin.
typedef std::map<TextureAtlasBuilderEx::SourceEx*, SkinResource*> SourceSkinMap;
SourceSkinMap sourceSkins;
// fetch all the skins from the catalog:
SkinResourceVector skins;
out._lib->getSkins( skins );
for(SkinResourceVector::iterator i = skins.begin(); i != skins.end(); ++i)
{
SkinResource* skin = i->get();
osg::Image* image = skin->createImage( _options );
if ( image )
{
// ensure we're not trying to atlas an atlas.
if ( image->r() > 1 )
{
OE_WARN << LC <<
"Found an image with more than one layer. You cannot create an "
"altas from another atlas. Stopping." << std::endl;
return false;
}
tab.addSource( image );
// re-write the URI to point at our new atlas:
skin->imageURI() = newAtlasURI;
// save the associate so we can come back later:
sourceSkins[tab.getSourceList().back().get()] = skin;
OE_INFO << LC << "Added skin: \"" << skin->name() << "\"" << std::endl;
}
else
{
OE_WARN << LC << "Failed to load image from catalog: \""
<< skin->name() << "\" ... skipped" << std::endl;
}
}
unsigned numSources = tab.getNumSources();
OE_INFO << LC << "Added " << numSources << " images ... building atlas ..." << std::endl;
// build the atlas images.
tab.buildAtlas();
const TextureAtlasBuilderEx::AtlasListEx& atlasList = tab.getAtlasList();
// create the target multi-layer image.
out._image = new osg::Image();
out._image->allocateImage(
_width,
_height,
atlasList.size(),
GL_RGBA,
GL_UNSIGNED_BYTE);
// initialize to all zeros
memset(out._image->data(), 0, out._image->getTotalSizeInBytesIncludingMipmaps());
// combine each of the atlas images into the corresponding "r" slot of the composed image:
for(int r=0; r<(int)atlasList.size(); ++r)
{
// copy the atlas image into the image array:
osg::Image* atlasImage = atlasList[r]->_image.get();
ImageUtils::PixelReader read (atlasImage);
ImageUtils::PixelWriter write(out._image.get());
for(int s=0; s<atlasImage->s(); ++s)
for(int t=0; t<atlasImage->t(); ++t)
write(read(s, t, 0), s, t, r);
// for each source in this atlas layer, apply its texture matrix info
// to the new catalog.
for(int k=0; k<atlasList[r]->_sourceList.size(); ++k)
{
TextureAtlasBuilderEx::SourceEx* source = atlasList[r]->_sourceList[k].get();
SourceSkinMap::iterator n = sourceSkins.find(source);
if ( n != sourceSkins.end() )
{
SkinResource* skin = n->second;
skin->imageLayer() = r;
skin->imageBiasS() = (float)source->_x/(float)atlasImage->s(); //(float)trans.x();
skin->imageBiasT() = (float)source->_y/(float)atlasImage->t(); //(float)trans.y();
skin->imageScaleS() = (float)source->_image->s()/(float)atlasImage->s();
skin->imageScaleT() = (float)source->_image->t()/(float)atlasImage->t();
}
}
}
return true;
}
