When all the input items are in place, we can start implementing a workflow. All the available algorithms can be found in the Algorithms tab on the left side of the modeler window.

Workflow implementation is very similar to manual execution of all steps of analysis: we add algorithms one by one, choosing the correct input and, if necessary, defining the output. While the modeler allows us to add parameters and algorithms in any random order, it is better to add algorithms in the same order in which they should be executed to avoid confusion. Let's start!

As you may remember, we did not add a separate input for grid extent, and you may be curious to know how we will extract it from the point layer in a format compatible with the modeler input. The answer is simple: we will use special tools, which are so-called modeler-only tools. What are these? Well, all the algorithms that are available exclusively in the Processing modeler are not available in the toolbox. Basically...