Shader editing

A computer system for editing a shader, the computer system comprising:

• one or more processors;
• and
• one or more storage devices storing:
• a graph corresponding to the shader, the graph comprising a plurality of entities connected together by one or more edges, wherein one or more of the entities each include a respective variable parameter, and wherein the graph comprises a root entity;
• an editor entity;
• and
• instructions that when executed by the one or more processors cause the one or more processors to perform a method, the method comprising:
• sending, from the editor entity, to an entity within the graph, a message, the message specifying a change in a value of the variable parameter of that entity within the graph;
• performing one or more times steps (i)-(ii) until the root entity receives a changed code fragment, thereby to provide a changed graph, wherein:
• step (i) comprises, responsive to an entity receiving a message, changing a code fragment of that entity based on the message received by that entity;
• and
• step (ii) comprises, responsive to changing a code fragment of an entity, sending, in a further message, the changed code fragment from that entity to a different entity within the graph that is connected to that entity within the graph via an edge;
• and,
• thereafter, modifying the shader based on the changed graph.

A non-transitory computer-readable storage medium storing a program or at least one of a plurality of programs arranged such that when executed by a computer system or one or more processors it/they cause the computer system or the one or more processors to perform a method, the method comprising:

• providing a graph corresponding to the shader, the graph comprising a plurality of entities connected together by one or more edges, wherein one or more of the entities each include a respective variable parameter, and wherein the graph comprises a root entity;
• sending, from an editor entity, to an entity within the graph, a message, the message specifying a change in a value of the variable parameter of that entity within the graph;
• responsive to the entity receiving the message, changing the variable parameter of that entity, wherein the changing the variable parameter of that entity causes a change in a code fragment of that entity;
• performing one or more times steps (i)-(ii) until a code fragment of the root entity is changed, thereby to provide a changed graph, wherein:
• step (i) comprises, responsive to changing a code fragment of an entity, sending, in a further message, that changed code fragment from that entity to a different entity within the graph that is connected to that entity within the graph via an edge;
• and
• step (ii) comprises, responsive to an entity receiving a further message, changing a code fragment of that entity based on the further message received by that entity;
• and,
• thereafter, modifying the shader based on the changed graph.