Starting with Blueprints.

• Your next "reading" assignment will be AEC Blueprints by Example.
  • This is just about two hours of video
  • And two quizzes.
  • This is a reasonable tutorial where he works through four different products.
    1. A door that opens when you approach and closes when you walk away.
    2. A light switch capable of switching multiple lights.
    3. A construction tool that snaps a light to the surface above it.
    4. A chair where the materials can be swapped by the user.
  • It introduces a number of very useful concepts.
• This is definitely a hands on lesson
  • You will need to get the demo material.
  • Instructions for getting this is on page two of material.pdf
  • This will place a new material in your vault.
• Starting the demo project
  • In my case, it wanted to install with a bad name.
    • Unreal apparently shortened the maximum length of names recently.
    • So when you start the new project, change AECBlueprintsbyExample to something shorter.
    • 
• Before you get started
  • Keep in mind that this is a very object oriented system.
    • When he talks about constructors, it is an object constructor.
  • There are many different "nodes" that are available for constructing a blueprint.
    • These are equivalent to the
      • Control constructs of a language (if, for, ...)
      • Set of functions in a language (cos, pow, ...)
      • Add on libraries.
    • What is more, we will build our own extension nodes in c++
    • You will need to
      • Know the different nodes available
      • Understand how these nodes work.
    • In the first case:
      • the search functions are "helpful"
      • And there is context dependent help.
      • But you just have to "learn" these nodes.
    • In the second case
      • The on line documentation
  • you will also lean some "algorithms"
• Notice in the video how he stresses the importance of
  • Design
  • Testing
  • Small code
• Also notice how he is very careful to keep his program neat.
• Let's build a simple object that changes text as we approach.
  • Talk about the design.
  • Step 1, make a new actor object blueprint.
    • Click in the Content Browser and select Blueprint Class
    • 
    • Select Actor
    • 
    • I called this ChangingText_BP
    • 
  • Double click on this to open the blueprint editor on this blueprint.
    • I added a Text Render object
    • I added a Box Collision object.
    • 
  • I want to explore, so I will build an constructor.
    • Click on Construction Script
    • 
    • This will open up the construction script editor with a single node in the graph.
  • The Construction Script node
    • Has a single output, a flow of control
    • Drag this off and add a print string node.
    • 
    • Change the text.
    • 
    • Save and compile this blueprint.
    • 
• Go back to the FirstPersonExampleMap and add this object.
  • Notice the constructor is called when the object is
    • Created
    • Moved.
  • We probably don't want it writing all the time so delete the print string node.
  • But remember it, it is essentially our cout statement for debugging.
• Add an array of text.
  • In the variables section, click on + to add a new variable.
  • 
  • Call it Quotes
  • In the Details panel on the upper left
    • Change the type to be array of text.
    • 
    • 
    • Save and compile, this will make it so you can predefined values.
    • Click on the + sign and add 4 spaces to the array.
    • 
    • Fill in the spaces with some snappy sayings.
  • This has just declared a local variable to the class.
  • Add an index variable as well.
    • Integer.
    • Scalar
    • 
    • Don't worry about an initial value, we will set it automatically.
  • Setting the index variable
    • Drag the Quotes variable onto the blueprint.
    • Select Get Quotes
    • From the data tab, drag a line and select Length
    • 
    • Drag a line from length, select Random Integer in Range
    • Connect length to the max.
    • Set the min to be 0.
    • 
    • Finish by setting the index variable.
    • 
  • Set the value of the text to display
    • I will drag down a reference to Text Render
    • Drag and get a Set Text node.
    • Just to be clean I will add another instance of Quotes
    • Drag and get a Get node
    • Connect
    • 
  • Save, compile, run game. Move object, ...
  • Mark the Quotes variable as Public by clicking on the icon to the right of the variable, or in the box.
    • 
    • This will make it so you can edit an instance of the object.
    •