/* ScummVM - Graphic Adventure Engine
 *
 * ScummVM is the legal property of its developers, whose names
 * are too numerous to list here. Please refer to the COPYRIGHT
 * file distributed with this source distribution.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 */

/*
 * Copyright (C) 2006-2010 - Frictional Games
 *
 * This file is part of HPL1 Engine.
 */

#include "hpl1/engine/scene/Camera2D.h"

#include "hpl1/engine/graphics/LowLevelGraphics.h"

namespace hpl {

//////////////////////////////////////////////////////////////////////////
// CONSTRUCTORS
//////////////////////////////////////////////////////////////////////////

//-----------------------------------------------------------------------

cCamera2D::cCamera2D(unsigned int alW, unsigned int alH) {
	mvPosition = cVector3f(0, 0, 0);
	mfAngle = 0;
	mvClipArea.x = alW;
	mvClipArea.y = alH;

	mfZMin = -100;
	mfZMax = -100;
	mfFOV = 60;
}

//-----------------------------------------------------------------------

cCamera2D::~cCamera2D() {
}

//-----------------------------------------------------------------------

//////////////////////////////////////////////////////////////////////////
// PUBLIC METHODS
//////////////////////////////////////////////////////////////////////////

//-----------------------------------------------------------------------

cVector3f cCamera2D::GetEyePosition() {
	cVector3f vEyePos = GetPosition();
	vEyePos.z = 100;
	return vEyePos;
}

//-----------------------------------------------------------------------

void cCamera2D::GetClipRect(cRect2f &aRect) {
	float fDiv = 1;
	if (mvPosition.z < 0) {
		fDiv = 1 - ABS(mvPosition.z / mfZMin);
		if (fDiv <= 0)
			fDiv = 0.0001f;
	} else
		fDiv = 1 + ABS(mvPosition.z / mfZMax);

	// Transform these depending on z
	float lW = ((float)mvClipArea.x) * fDiv;
	float lH = ((float)mvClipArea.y) * fDiv;

	float lX = mvPosition.x - lW / 2;
	float lY = mvPosition.y - lH / 2;

	aRect.x = lX;
	aRect.y = lY;
	aRect.w = lW;
	aRect.h = lH;
}

//-----------------------------------------------------------------------

void cCamera2D::SetModelViewMatrix(iLowLevelGraphics *apLowLevel) {
	apLowLevel->SetIdentityMatrix(eMatrix_ModelView);

	cRect2f ClipRect;
	GetClipRect(ClipRect);
	cVector2f vVirtSize = apLowLevel->GetVirtualSize();
	cVector3f vPos(-(ClipRect.x), -(ClipRect.y), 0);
	cVector3f vScale(vVirtSize.x / ClipRect.w, vVirtSize.y / ClipRect.h, 1);

	apLowLevel->ScaleMatrix(eMatrix_ModelView, vScale);
	apLowLevel->TranslateMatrix(eMatrix_ModelView, vPos);
}

void cCamera2D::SetProjectionMatrix(iLowLevelGraphics *apLowLevel) {
	apLowLevel->SetOrthoProjection(apLowLevel->GetVirtualSize(), -1000, 1000);
}

//-----------------------------------------------------------------------

} // namespace hpl