Printing with multiple carriages

A printing apparatus comprising:

• a first carriage moveable along an axis, the first carriage comprising a first print agent dispenser to selectively eject a first set of print agents;
• a second carriage moveable along the axis, the second carriage comprising a second print agent dispenser to selectively eject a second set of print agents;
• and
• a controller to:
• receive data corresponding to a print job;
• determine a first delay between a build material layer generation and ejection of a first amount of the first set of print agents at a print area based on the received data;
• determine a second amount of the second set of print agents to be ejected at the print area based on the received data;
• determine a second delay between the ejection of the first amount of the first set of print agents and the second amount of the second set of print agents at the print area;
• and
• independently control movement of the first carriage and the second carriage and the ejection of the first amount of the first set of print agents from the first carriage and the second amount of the second set of print agents from the second print agent dispenser based on the first delay and the second delay to complete the print job.

A method comprising:

• generating a build material layer on a platform;
• determining a first amount of a first set of print agents and a second amount of a second set of print agents to be ejected at a print area based on data corresponding to a 3D object to be generated, wherein a first carriage comprising a first print agent dispenser is to eject the first set of print agents and a second carriage comprising a second print agent dispenser is to eject the second set of print agents;
• determining a first delay between generation of the build material layer and ejection of the first amount of the first set of print agents at the print area;
• determining a second delay between ejection of the first amount of the first set of print agents and the second amount of the second set of print agents at the print area;
• moving the first carriage and the second carriage along an axis and ejecting the first amount of the first set of print agents from the first print agent dispenser and the second amount of the second set of print agents from the second print agent dispenser based on the determined second delay to generate the 3D object.