Engine.CameraModifier

/**
 * Copyright 1998-2007 Epic Games, Inc. All Rights Reserved.
 */
class CameraModifier extends Object
    native;

/* Interface class for all camera modifiers applied to
    a player camera actor. Sub classes responsible for
    implementing declared functions.
*/

/* Do not apply this modifier */
var protected   bool    bDisabled;
/* This modifier is still being applied and will disable itself */
var             bool    bPendingDisable;

/** Camera this object is attached to */
var Camera  CameraOwner;


//debug
var(Debug) bool bDebug;

/** Allow anything to happen right after creation */
function Init();


/**
 * Directly modifies variables in the camera actor
 *
 * @param   Camera      reference to camera actor we are modifiying
 * @param   DeltaTime   Change in time since last update
 * @param   OutPOV      current Point of View, to be updated.
 * @return  bool        TRUE if should STOP looping the chain, FALSE otherwise
 */
function bool ModifyCamera
(
        Camera  Camera,
        float   DeltaTime,
    out TPOV    OutPOV
);


/**
 * Camera modifier evaluates itself vs the given camera's modifier list
 *  and decides whether to add itself or not
 *
 * @parma   Camera - reference to camera actor we want add this modifier to
 * @output  bool   - TRUE if modifier added to camera's modifier list, FALSE otherwise
 */
function bool AddCameraModifier( Camera Camera )
{
    //debug
    if (bDebug) LogInternal(self@"AddModifier"@Camera.ModifierList.Length);

    CameraOwner = Camera;

    // Default implementation adds self and always returns true
    Camera.ModifierList[Camera.ModifierList.Length] = self;
    return true;
}

/**
 * Camera modifier removes itself from given camera's modifier list
 *
 * @param   Camera  - reference to camara actor we want to remove this modifier from
 * @output  bool    - TRUE if modifier removed successfully, FALSE otherwise
 */
function bool RemoveCameraModifier( Camera Camera )
{
    local int ModifierIdx;

    //debug
    if (bDebug) LogInternal(self@"RemoveModifier");

    // Loop through each modifier in camera
    for( ModifierIdx = 0; ModifierIdx < Camera.ModifierList.Length; ModifierIdx++ )
    {
        // If we found ourselves, remove ourselves from the list and return
        if( Camera.ModifierList[ModifierIdx] == self )
        {
            Camera.ModifierList.Remove(ModifierIdx, 1);
            return true;
        }
    }

    // Didn't find ourselves in the list
    return false;
}

/** Accessor function to check if modifier is inactive */
simulated function bool IsDisabled()
{
    return bDisabled;
}

/** Accessor functions for changing disable flag */
function DisableModifier()
{
    //debug
    if (bDebug) LogInternal(self@"DisableModifier");

    bDisabled = true;
    bPendingDisable = false;
}
function EnableModifier()
{
    //debug
    if (bDebug) LogInternal(self@"EnableModifier");

    bDisabled = false;
    bPendingDisable = false;
}
function ToggleModifier()
{
    //debug
    if (bDebug) LogInternal(self@"ToggleModifier");

    if( bDisabled )
    {
        EnableModifier();
    }
    else
    {
        DisableModifier();
    }
}
/**
 * Allow this modifier a chance to change view rotation and deltarot
 * Default just returns ViewRotation unchanged
 * @return  bool - TRUE if should stop looping modifiers to adjust rotation, FALSE otherwise
 */
simulated function bool ProcessViewRotation( Actor ViewTarget, float DeltaTime, out Rotator out_ViewRotation, out Rotator out_DeltaRot );

defaultproperties
{
   Name="Default__CameraModifier"
   ObjectArchetype=Object'Core.Default__Object'
}