Blueprint Mutator Tutorial - Low Grav

Blueprint Mutator Tutorial - Low Grav

This tutorial will teach you how to make a Low Grav mutator for UT using only Blueprints. I over explained some blueprint mechanics to help those who are just starting out.

Requirements

  • Engine version: 4.3
  • Skill level: beginner

Create the Blueprint

  • In the Content Browser, hit the new button.
  • Select Blueprint from the dropdown menu.

Lowgravtutorial newblueprint.png

  • Enter UTMutator in the Search box of the Custom Classes box.
  • Select UTMutator and then hit the Select button.

Lowgravtutorial pickutmutator.png

  • Name the Blueprint "Mutator_LowGrav".

Edit the Blueprint

  • Double click your new "Mutator_LowGrav" Blueprint to open it in the Blueprint Editor.
  • Click the Graph button in the upper right
  • Click the +V (Add Variable) button
  • Change the variable name to "NewGravity", check the Editable checkbox

Lowgravtutorial newvariable.png

  • Click the Compile button in the upper left of the window
  • Click the Defaults button, then set the value of NewGravity to -250
  • Return to the Graph view by clicking the Graph button again in the upper right of the window
  • If you're not in the "Event Graph" tab, double click the EventGraph text in the My Blueprint panel
  • Right click the empty graph and select "Add Event", then select "Begin Play" to place the "Begin Play" event
  • Right click the empty graph again and search for "Get Game Mode", select "Get Game Mode" to place the "Get Game Mode" node
  • Drag off of the "Get Game Mode" Return Value to bring up the node search box again, select "Cast To UTGameMode" to place our cast node
  • Connect the "Begin Play" event to the "Cast To UTGameMode" node
  • Drag off of the "As UTGame Mode" Return Value to bring up the node search box, select "Set World Gravity" to place the node
  • Drag the NewGravity variable from the My Blueprint panel over to the NewGravity input on the Event Graph
  • Compile and Save the Blueprint

Lowgravtutorial eventgraph.png

Testing the Blueprint

  • Hit the drop down arrow on the Play button and select "Advanced Settings"
  • In the "Server Game Options" edit box of the "Multiplayer Options" section, enter
    ?mutator=/Game/RestrictedAssets/Blueprints/Mutator_LowGrav.Mutator_LowGrav_C
    • The path needs to match the folder that you placed the blueprint in, I've used the place where the shipped example blueprint lives
  • Hit the play button and you should now have reduced gravity
    • If you do not, examine the output logs to verify that the mutator loaded successfully. You may see a warning like "LogUObjectGlobals:Warning: Failed to find object 'Class /Game/WrongPath/Mutator_LowGrav_C'", in that case double check the path that you entered in the "Server Game Options"