/*
** gl_dynlight1.cpp
** dynamic light application
**
**---------------------------------------------------------------------------
** Copyright 2002-2005 Christoph Oelckers
** All rights reserved.
**
** Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions
** are met:
**
** 1. Redistributions of source code must retain the above copyright
**    notice, this list of conditions and the following disclaimer.
** 2. Redistributions in binary form must reproduce the above copyright
**    notice, this list of conditions and the following disclaimer in the
**    documentation and/or other materials provided with the distribution.
** 3. The name of the author may not be used to endorse or promote products
**    derived from this software without specific prior written permission.
** 4. When not used as part of GZDoom or a GZDoom derivative, this code will be
**    covered by the terms of the GNU Lesser General Public License as published
**    by the Free Software Foundation; either version 2.1 of the License, or (at
**    your option) any later version.
** 5. Full disclosure of the entire project's source code, except for third
**    party libraries is mandatory. (NOTE: This clause is non-negotiable!)
**
** THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
** IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
** OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
** IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
** INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
** NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
** THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
**---------------------------------------------------------------------------
**
*/

#include "gl/system/gl_system.h"
#include "c_dispatch.h"
#include "p_local.h"
#include "vectors.h"
#include "gl/gl_functions.h"
#include "g_level.h"

#include "gl/system/gl_interface.h"
#include "gl/renderer/gl_renderer.h"
#include "gl/renderer/gl_lightdata.h"
#include "gl/data/gl_data.h"
#include "gl/dynlights/gl_dynlight.h"
#include "gl/scene/gl_drawinfo.h"
#include "gl/scene/gl_portal.h"
#include "gl/shaders/gl_shader.h"
#include "gl/textures/gl_material.h"


//==========================================================================
//
// Light related CVARs
//
//==========================================================================

CUSTOM_CVAR (Bool, gl_lights, true, CVAR_ARCHIVE | CVAR_GLOBALCONFIG | CVAR_NOINITCALL)
{
	if (self) gl_RecreateAllAttachedLights();
	else gl_DeleteAllAttachedLights();
}

CVAR (Bool, gl_attachedlights, true, CVAR_ARCHIVE | CVAR_GLOBALCONFIG);
CVAR (Bool, gl_lights_checkside, true, CVAR_ARCHIVE | CVAR_GLOBALCONFIG);
CVAR (Float, gl_lights_intensity, 1.0f, CVAR_ARCHIVE | CVAR_GLOBALCONFIG);
CVAR (Float, gl_lights_size, 1.0f, CVAR_ARCHIVE | CVAR_GLOBALCONFIG);
CVAR (Bool, gl_light_sprites, true, CVAR_ARCHIVE | CVAR_GLOBALCONFIG);
CVAR (Bool, gl_light_particles, true, CVAR_ARCHIVE | CVAR_GLOBALCONFIG);

//==========================================================================
//
// Sets up the parameters to render one dynamic light onto one plane
//
//==========================================================================
bool gl_GetLight(int group, Plane & p, ADynamicLight * light, bool checkside, FDynLightData &ldata)
{
	int i = 0;

	DVector3 pos = light->PosRelative(group);
	
	float dist = fabsf(p.DistToPoint(pos.X, pos.Z, pos.Y));
	float radius = (light->GetRadius() * gl_lights_size);
	
	if (radius <= 0.f) return false;
	if (dist > radius) return false;
	if (checkside && gl_lights_checkside && p.PointOnSide(pos.X, pos.Z, pos.Y))
	{
		return false;
	}


	float cs;
	if (light->IsAdditive()) 
	{
		cs = 0.2f;
		i = 2;
	}
	else 
	{
		cs = 1.0f;
	}

	float r = light->GetRed() / 255.0f * cs * gl_lights_intensity;
	float g = light->GetGreen() / 255.0f * cs * gl_lights_intensity;
	float b = light->GetBlue() / 255.0f * cs * gl_lights_intensity;

	if (light->IsSubtractive())
	{
		Vector v;
		
		v.Set(r, g, b);
		r = v.Length() - r;
		g = v.Length() - g;
		b = v.Length() - b;
		i = 1;
	}

	float *data = &ldata.arrays[i][ldata.arrays[i].Reserve(8)];
	data[0] = pos.X;
	data[1] = pos.Z;
	data[2] = pos.Y;
	data[3] = radius;
	data[4] = r;
	data[5] = g;
	data[6] = b;
	data[7] = 0;
	return true;
}