Build layer coverage analysis

An apparatus for generating a three-dimensional object, the apparatus comprising:

• a build material distributor to distribute respective build layers of build material in a build area of the apparatus;
• at least one build material heating element to heat the build material prior to distribution in the build area by the build material distributor;
• and,
• a controller configured to:
• determine a first build layer temperature of a location of a first build layer;
• control the build material distributor to distribute a second build layer in the build area onto, adjacent to, and over the first build layer;
• determine a second build layer temperature of a corresponding location of the second build layer;
• compare the first build layer temperature to the second build layer temperature;
• based on the comparison, determine if a sufficient amount of build material has been distributed at the corresponding location of the second build layer;
• control the build material distributor to selectively recoat the second build layer with additional build material based on the determining if a sufficient amount of build material has been distributed at the corresponding location of the second build layer;
• and,
• prior to controlling the build material distributor to distribute the second build layer, control the at least one build material heating element to thereby heat the build material to be distributed as the second build layer based at least in part on the first build layer temperature of the location of the first build layer.