Additive manufacturing with fusing and warming energy sources

A non-transitory machine-readable storage medium storing instructions that when by a processor, cause the processor to perform processing comprising:

• controlling a fusing agent deposition device to deposit a fusing agent on a first portion of a layer of build material that is to form a three-dimensional (3D) object, wherein the fusing agent has a first absorption spectrum;
• controlling a warming agent deposition device to deposit a warming agent on a second portion of the layer, wherein the warming agent has a second absorption spectrum different than the first absorption spectrum;
• controlling a warming energy source with a second emission spectrum to deliver energy to the layer of build material such that the second portion is heated to a temperature below a melting temperature of the build material;
• and
• controlling a fusing energy source with a first emission spectrum to deliver energy to the layer of build material such that the first portion is heated to the melting temperature,
• wherein controlling the warming agent deposition device to deposit the warming agent and controlling the warming energy source with the second emission spectrum are based on an amount of absorption of the second portion from the fusing energy source, and
• wherein controlling the fusing agent deposition device to deposit the fusing agent and controlling the fusing energy source with the first emission spectrum are based on an amount of absorption of the first portion from the warming energy source.

An additive manufacturing system comprising:

• a fusing agent deposition device configured to deposit a fusing agent on a first portion of a layer of build material that is to form a three-dimensional (3D) object, wherein the fusing agent has a first absorption spectrum;
• a warming agent deposition device configured to deposit a warming agent on a second portion of the layer, wherein the warming agent has a second absorption spectrum different than the first absorption spectrum;
• a warming energy source with a second emission spectrum configured to deliver energy to the layer of build material such that the second portion is heated to a temperature below a melting temperature of the build material;
• and
• a fusing energy source with a first emission spectrum configured to deliver energy to the layer of build material such that the first portion is heated to the melting temperature,
• wherein the warming agent deposition device is to deposit the warming agent and the warming energy source is to deliver the energy with the second emission spectrum based on an amount of absorption of the second portion from the fusing energy source, and
• wherein the fusing agent deposition device is to deposit the fusing agent and the fusing energy source is to deliver the energy with the first emission spectrum based on an amount of absorption of the first portion from the warming energy source.