UE2 - UT2kX Lens Flares in Skybox

//-----------------------------------------------------------
// FlareInteraction.
// Adds 1337 lens flares for lights w/ coronas.
// (c) 2002 jasonyu
//-----------------------------------------------------------
class FlareInteraction extends Interaction;
 
#exec OBJ LOAD FILE=..\Textures\HaloTC_LensFlares.utx
 
var Actor PlayerOwner;
const HLSMAX = 240;
const RGBMAX = 255;
 
event Initialized()
{
	PlayerOwner = ViewportOwner.Actor;
	log("Lensflare interaction initialized.");
}
 
// adapted from:
// http://plaza27.mbn.or.jp/~satomii/design/win32/hls2rgb.html
final simulated function float HueToRGB(float n1, float n2, float hue)
{
	if ( hue < 0 ) hue += HLSMAX;
	if ( hue > HLSMAX ) hue -= HLSMAX;
 
	/* return r,g, or b value from this tridrant */
	if ( hue < (HLSMAX/6) )
		return ( n1 + (((n2-n1)*hue + (HLSMAX/12))/(HLSMAX/6)) );
	if ( hue < (HLSMAX/2) )
		return n2;
	if ( hue < ((HLSMAX*2)/3) )
		return ( n1 + (((n2-n1)*(((HLSMAX*2)/3)-hue) + (HLSMAX/12))/(HLSMAX/6)) );
	else
		return n1;
}
 
final simulated function Color hls2rgb(byte hue, byte lum, byte sat)
{
	local Color C;
	local float Magic1, Magic2;
	local int R,G,B;
 
	if ( sat==0)
	{     /* achromatic case */
		C.R = (lum*RGBMAX) / HLSMAX;
		C.G = C.R;
		C.B = C.R;
	}
	else
	{       /* chromatic case */
		/* set up magic numbers */
		if (lum <= (HLSMAX/2))
			Magic2 = (lum*(HLSMAX+sat)+(HLSMAX/2)) / HLSMAX;
		else
			Magic2 = lum+sat - ((lum*sat)+(HLSMAX/2)) / HLSMAX;
 
		Magic1 = 2*lum - Magic2;
 
		/* get RGB, change units from HLSMAX to RGBMAX */
		R = (HueToRGB(Magic1, Magic2, hue+(HLSMAX/3))
				* RGBMAX + (HLSMAX/2)) / HLSMAX;
		G = (HueToRGB(Magic1, Magic2, hue)
				* RGBMAX + (HLSMAX/2)) / HLSMAX;
 
		B = (HueToRGB(Magic1, Magic2, hue-(HLSMAX/3))
				* RGBMAX + (HLSMAX/2)) / HLSMAX;
	}
 
	C.R = R;
	C.G = G;
	C.B = B;
	C.A = 255;
	return C;
}
 
// adapted from:
// http://www.gamedev.net/reference/articles/article813.asp
simulated function PostRender( canvas Canvas )
{
	local Light Other;
	local float Dist;
	local Vector X,Y,Z, Dir;
 
	local Vector V, C, L;
	local float Length;
	local float ScaleX, ScaleY;
 
 
	if ( ViewportOwner.Actor.Pawn != None ) PlayerOwner = ViewportOwner.Actor.Pawn;
	else PlayerOwner = ViewportOwner.Actor;
 
	if ( PlayerOwner != None )
	{
		ScaleX = Canvas.SizeX / 640.0;
		ScaleY = Canvas.SizeY / 480.0;
 
		C.X = Canvas.ClipX/2;
		C.Y = Canvas.ClipY/2;
		GetAxes(PlayerOwner.Rotation, X,Y,Z);
		ForEach PlayerOwner.RadiusActors(class'Light', Other, 2000)
		{
			Dir = Other.Location - PlayerOwner.Location;
			Dist = VSize(Dir);
			Dir = Dir/Dist;
 
			// find an appropriate light source (bright, in FOV)
			if ( (Dir Dot X) > 0.7 && Other.bCorona &&
				(
				(PlayerOwner.IsA('Pawn') &&  Pawn(PlayerOwner).LineOfSightTo(Other) ) ||
				(PlayerOwner.IsA('Controller') && Controller(PlayerOwner).LineOfSightTo(Other) )
				) &&
				Other.LightRadius >= 64 && Other.DrawScale > 0.2 )
			{
				//Convert 3d location to 2d for display on the Canvas
				L = WorldToScreen(Other.location);
 
				V.X = L.X - C.X;
				V.Y = L.Y - C.Y;
				Length = VSize(V);
				V = Normal(V);
 
				Canvas.Style = PlayerOwner.ERenderStyle.STY_Additive;
 
				// tint the corona textures to match the hue of the light
				Canvas.DrawColor = hls2rgb(Other.LightHue, 15, 75);
 
				// place flares along directional vector
				Canvas.SetPos( (V.X*Length*1.2)-32*ScaleX+C.X, (V.Y*Length*1.2)-32*ScaleY+C.Y );
				Canvas.DrawTile(Texture'flares_generic_bitmap_2', 64*ScaleX,64*ScaleY,0.0, 0.0, 32, 32);
 
				Canvas.SetPos( (V.X*Length)-32*ScaleX+C.X, (V.Y*Length)-32*ScaleY+C.Y );
				Canvas.DrawTile(Texture'flares_generic_bitmap_3', 64*ScaleX,64*ScaleY,0.0, 0.0, 16, 16);
 
				Canvas.SetPos( (V.X*Length*0.66)-64*ScaleX+C.X, (V.Y*Length*0.66)-64*ScaleY+C.Y );
				Canvas.DrawTile(Texture'flares_generic_bitmap_4', 128*ScaleX,128*ScaleY,0.0, 0.0, 32, 32);
 
				Canvas.SetPos( (V.X*Length*0.33)-64*ScaleX+C.X, (V.Y*Length*0.33)-64*ScaleY+C.Y );
				Canvas.DrawTile(Texture'flares_generic_bitmap_5', 128*ScaleX,128*ScaleY,0.0, 0.0, 32, 32);
 
				Canvas.SetPos( (V.X*Length*0.125)-64*ScaleX+C.X, (V.Y*Length*0.125)-64*ScaleY+C.Y );
				Canvas.DrawTile(Texture'flares_generic_bitmap_6', 128*ScaleX,128*ScaleY,0.0, 0.0, 16, 16);
 
				Canvas.SetPos( (V.X*Length*-0.21)-64*ScaleX+C.X, (V.Y*Length*-0.21)-64*ScaleY+C.Y );
				Canvas.DrawTile(Texture'flares_generic_bitmap_7', 128*ScaleX,128*ScaleY,0.0, 0.0, 64, 64);
 
				Canvas.SetPos( (V.X*Length*-0.30)-32*ScaleX+C.X, (V.Y*Length*-0.30)-32*ScaleY+C.Y );
				Canvas.DrawTile(Texture'flares_generic_bitmap_3', 64*ScaleX,64*ScaleY,0.0, 0.0, 16, 16);
 
				Canvas.SetPos( (V.X*Length*-0.5)-90*ScaleX+C.X, (V.Y*Length*-0.5)-90*ScaleY+C.Y );
				Canvas.DrawTile(Texture'flares_generic_bitmap_3', 180*ScaleX,180*ScaleY,0.0, 0.0, 16, 16);
			}
		}
	}
}
 
defaultproperties
{
   bVisible=true
   bActive=true
}