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+@page primer_cards A Primer on Cards
+
+# The Cockatrice Card Library
+
+All non-gui code related to cards used by Cockatrice is contained within libcockatrice_card.
+
+# A Basic Card Object: CardInfo
+
+A CardInfo object is the translational unit used by the CardDatabase to represent an on-disk XML entry as an in-memory
+Qt object.
+
+For a complete overview of the fields that define a CardInfo object, see the class documentation and more specifically
+@ref PrivateCardProperties.
+
+These fields correspond to either entries or a combination of entries in the XML card entry to which the
+CardDatabaseParser applies special logic to map, populate or determine their respective values in the CardInfo object.
+
+Any property to which special parsing is not applied is stored in CardInfo::properties and may be retrieved or set with
+CardInfo::getProperty() or CardInfo::setProperty() as well as CardInfo::getProperties() to get a collection of the
+property keys a CardInfo contains.
+
+For more information on how special fields contained within @ref PrivateCardProperties are parsed, see
+CockatriceXml4Parser::loadCardsFromXml().
+
+Apart from access to the basic and extended properties of a card, CardInfo also provides two important mechanisms to us.
+The first is the CardInfo::pixmapUpdated() signal, which allows the CardPictureLoader to signal when it is done
+manipulating (in most cases: loading) the QPixmap of an ExactCard::getPixmapCacheKey(), where the ExactCard::card
+corresponds to this CardInfo object.
+
+Put simply: Whenever the CardPictureLoader loads a new PrintingInfo which is not already in the cache, it emits this
+signal so that any widget using a CardInfo object can update the display of it to possibly use this new QPixmap.
+
+\attention It should be noted that it is not possible to use CardPictureLoader::getPixmap() with anything but an
+ExactCard, which is a CardInfo object associated with a PrintingInfo, i.e. a definitive printing of a specific card
+
+The other signal, CardInfo::cardInfoChanged() conceptually works much the same way, except it is concerned with the
+properties of the CardInfo object.
+
+# Getting specific: PrintingInfo and ExactCard
+
+## Printing Info
+
+A CardInfo object describes the basic properties of a card in much the same way that we say "Two cards with the same
+name are and should be equal if their properties are equal". However, there are certain (mostly visual) properties which
+might differ between printings of a card but still conceptually classify two instances of a card as "the same card".
+The most obvious example to this are cards which fundamentally share all properties except the artwork depicted on the
+card.
+
+We refer to such differences as Printings and track them in the PrintingInfo class. A PrintingInfo is always related to
+the CardSet that introduced the variation. Multiple variations can exist in the same CardSet and the respective
+PrintingInfo::getProperty() can be used to determine the differences, such as the collector numbers on the printings, if
+there are any.
+
+## Exact Card
+
+A CardInfo object is used to hold the functional properties of a card and a PrintingInfo object can be used to hold the
+visual properties of a card. To represent a 'physical' card, as in, a concrete immutable instance of a card, we can use
+ExactCard, which combines a CardInfo and a PrintingInfo object into one class. The class is used as a container around
+CardInfo objects whenever the user (and thus the program) expects to be presented with a defined card printing.
+
+# Using Cards
+
+For more information on the XML database schema which the CardDatabaseParser parses to generate CardInfo objects, see
+@ref card_database_schema_and_parsing.
+
+For more information on querying the CardDatabase for CardInfo objects, see @ref querying_the_card_database.
+
+For more information on displaying CardInfo and ExactCard objects using Qt Widgets, see @ref displaying_cards.
+
+For more information on how card pictures are loaded from disk or the network, see @ref loading_card_pictures as well as
+the CardPictureLoader documentation.