CurrentMovement

Introduction

The CurrentMovement property controls the values used by the top down entity in response to input. The CurrentMovement property can be assigned in code in response to various conditions in your game such as:

• Collision with different terrain (such as walking through mud)

• Responding to power-ups (such as collecting a power-up which increases speed)

• Responding to special moves or input which changes the character's movement variables (such as holding down a run button)

Defining Movement Values

Movement values can be defined in the FRB editor or code. If your game has a limited set of movement values, these can be defined in the FRB editor. To do so:

1. Select an entity

2. Click the Entity Input Movement tab

3. Verify that your entity is using the Top Down option for Input Movement Type

4. Click the Add Movement Type button

   

   Add Movement Type button
5. Modify the newly-added movement values as necessary

The Top Down tab displays all movement values for the selected entity.

All movement values displayed in the FRB Editor

Assigning Movement Values

You can assign the current movement values in code through the CurrentMovement propety. For example, the following code assigns the movement to FastMovement or Default depending on the state of an Xbox360GamePad:

var gamepad = InputManager.Xbox360GamePads[0];
if(gamepad.ButtonDown(Xbox360GamePad.Button.B))
{
    this.CurrentMovement = TopDownValues[DataTypes.TopDownValues.FastMovement];
}
else
{
    this.CurrentMovement = TopDownValues[DataTypes.TopDownValues.Default];
}

Movement Values and Inheritance

Derived entities can override movement values which are defined by their base entity. For example, consider an Enemy entity with two movement types: Idle and Walk.

Enemy with movement values

A derived entity automatically inherits these movement values as shown in the FRB editor.

Inherited values

Notice that these values are read-only, but they can be overwritten by checking the Overwrite Values radio button.

Overwritten walk variable

The name of movement types cannot be changed when overwriting values; however derived entities can add additional movement variables which do not exist in their base.

At runtime the derived entity merges the overwritten values with the base values. For example, the Slime enemy has two movement values, but its Walk value has a max speed of 150 instead of 76.

MaxSpeed set to the overwritten value of 150

This merging occurs in the generated code for each entity. For example, the following shows what the code in Enemy.Generated.cs looks like. Notice that it merges the base TopDownValuesStatic with its own values.

if (TopDownValuesStatic == null)
{
    {
        // We put the { and } to limit the scope of oldDelimiter
        char oldDelimiter = FlatRedBall.IO.Csv.CsvFileManager.Delimiter;
        FlatRedBall.IO.Csv.CsvFileManager.Delimiter = ',';
        System.Collections.Generic.Dictionary<string, global::TopDownExample.DataTypes.TopDownValues> temporaryCsvObject = new System.Collections.Generic.Dictionary<string, global::TopDownExample.DataTypes.TopDownValues>();
        foreach (var kvp in Entities.Enemy.TopDownValuesStatic)
        {
            temporaryCsvObject.Add(kvp.Key, kvp.Value);
        }
        FlatRedBall.IO.Csv.CsvFileManager.CsvDeserializeDictionary<string, global::TopDownExample.DataTypes.TopDownValues>("Content/Entities/Slime/TopDownValuesStatic.csv", temporaryCsvObject, FlatRedBall.IO.Csv.DuplicateDictionaryEntryBehavior.Replace);
        FlatRedBall.IO.Csv.CsvFileManager.Delimiter = oldDelimiter;
        TopDownValuesStatic = temporaryCsvObject;
    }
}