Digital content automated layout system

In a digital medium digital content design rendering environment, a method implemented by a computing device, the method comprising:

• receiving, by the computing device, a single digital content design that includes single instances, respectively, of a plurality of items of digital content and a layout definition including a set of rules included in a decision tree that specify an up/down arrangement or a side-to-side arrangement of the single instances of the items of digital content within hierarchical groupings;
• and
• controlling, by the computing device, arrangement of the single instances of items of digital content to render the single digital content design by executing the set of rules that are configured to respond to differences in an amount of an available display area in a user interface, the controlling including:
• detecting an amount of display area available in the user interface along a primary axis;
• determining whether to employ the up/down arrangement or the side-by-side arrangement for a portion of the single instances of the items of digital content within the respective said hierarchical grouping based on the amount of display area, the up/down arrangement employed when a number of items within the respective said hierarchical grouping is odd, the side-by-side arrangement employed when the number of items within the respective said hierarchical grouping is even;
• and
• displaying the portion of the single instances of the items of digital content within the respective said hierarchical grouping in the user interface as having the determined up/down arrangement or the determined side-by-side arrangement.

In a digital content design creation environment, a layout system comprising:

• a layout arrangement module implemented at least partially in hardware of a computing device to;
• receive a single digital content design having single instances, respectively, of items of digital content that are displayable as part of the single digital content design;
• and
• determine a layout of items of digital content with respect to each other within the single digital content design;
• a layout tree determination module implemented at least partially in hardware of the computing device to determine a layout tree having a plurality of layout nodes that describe an arrangement of hierarchical groupings of the items of digital content in the determined layout with respect to primary and secondary axes;
• a decision tree generation module implemented at least partially in hardware of the computing device to generate a decision tree based on the layout tree, the decision tree including a set of rules based on an available display area in a user interface along the primary axis and then the secondary axis, the set of rules included in the decision tree including at least one said rule specifying an up/down arrangement when a number of items within a respective said hierarchical grouping is odd or a side-to-side arrangement for a portion of the items when a number of items of digital content within the respective said hierarchical grouping is even;
• and
• a layout definition generation module implemented at least partially in hardware of the computing device to:
• convert the decision tree into a layout definition having the set of rules;
• and
• include the layout definition in the single digital content design that includes the single instances, respectively, of the items of digital content, the layout definition in which the set of rules are executable by a subsequent computing device to control the up/down arrangement and the side-to-side arrangement of the portion of the single instances of the items of digital content to respond to differences in an amount of an available display area in a user interface of the subsequent computing device.