1

public/dlight.h

@@ -0,0 +1,84 @@
+//========= Copyright Valve Corporation, All rights reserved. ============//
+//
+// Purpose: 
+//
+// $NoKeywords: $
+//
+//=============================================================================//
+#if !defined ( DLIGHTH )
+#define DLIGHTH
+#ifdef _WIN32
+#pragma once
+#endif
+
+#include "mathlib/vector.h"
+
+//-----------------------------------------------------------------------------
+// Dynamic light structure
+//-----------------------------------------------------------------------------
+
+enum
+{
+	DLIGHT_NO_WORLD_ILLUMINATION = 0x1,
+	DLIGHT_NO_MODEL_ILLUMINATION = 0x2,
+
+	// NOTE: These two features are used to dynamically tweak the alpha on displacements
+	// which is a special effect for selecting which texture to use. If 
+	// we ever change how alpha is stored for displacements, we'll have to kill this feature
+	DLIGHT_ADD_DISPLACEMENT_ALPHA = 0x4,
+	DLIGHT_SUBTRACT_DISPLACEMENT_ALPHA = 0x8,
+	DLIGHT_DISPLACEMENT_MASK = (DLIGHT_ADD_DISPLACEMENT_ALPHA | DLIGHT_SUBTRACT_DISPLACEMENT_ALPHA),
+};
+
+// This is the lighting value that is used to determine when something can be 
+// culle from lighting because it is close enough to black to be virtually black.
+//#define MIN_LIGHTING_VALUE	(1.0f/256.0f)
+
+// This is the broken value of MIN_LIGHTING_VALUE that we have to take into consideration
+// to make sure that the lighting for dlights look the same as they did in HL2.
+// We'll use the real MIN_LIGHTING_VALUE above to calculate larger radii for dynamic
+// light sources.
+//#define HL2_BROKEN_MIN_LIGHTING_VALUE (20.0f/256.0f)
+
+struct dlight_t
+{
+	int		flags;
+	Vector	origin;
+	float	radius;
+	ColorRGBExp32	color;		// Light color with exponent
+	float	die;				// stop lighting after this time
+	float	decay;				// drop this each second
+	float	minlight;			// don't add when contributing less
+	int		key;
+	int		style;				// lightstyle
+
+	// For spotlights. Use m_OuterAngle == 0 for point lights
+	Vector	m_Direction;		// center of the light cone
+	float	m_InnerAngle;
+	float	m_OuterAngle;
+
+	// see comments above about HL2_BROKEN_MIN_LIGHTING_VALUE and MIN_LIGHTING_VALUE
+	// THIS SHOULD ONLY GET CALLED FROM THE ENGINE
+	float GetRadius() const
+	{
+//		return FastSqrt( radius * radius * ( HL2_BROKEN_MIN_LIGHTING_VALUE / MIN_LIGHTING_VALUE ) );
+		return radius;
+	}
+
+	// see comments above about HL2_BROKEN_MIN_LIGHTING_VALUE and MIN_LIGHTING_VALUE
+	// THIS SHOULD ONLY GET CALLED FROM THE ENGINE
+	float GetRadiusSquared() const
+	{
+//		return radius * radius * ( HL2_BROKEN_MIN_LIGHTING_VALUE / MIN_LIGHTING_VALUE );
+		return radius * radius;
+	}
+
+	// THIS SHOULD ONLY GET CALLED FROM THE ENGINE
+	float IsRadiusGreaterThanZero() const
+	{
+		// don't bother calculating the new radius if you just want to know if it is greater than zero.
+		return radius > 0.0f;
+	}
+};
+
+#endif