genesis-3d_engine/Engine/graphicsystem/Camera/CameraSetting.cc

/****************************************************************************
Copyright (c) 2011-2013,WebJet Business Division,CYOU

http://www.genesis-3d.com.cn

Permission is hereby granted, free of charge, to any person obtaining a copy
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****************************************************************************/
#include "stdneb.h"
#include "Camera/CameraSetting.h"
#include "foundation/math/float3.h"

namespace Graphic
{
	using namespace Math;

	//------------------------------------------------------------------------------
	/**
	*/
	CameraSetting::CameraSetting() :
	viewProjDirty(true),
		viewMatrix(matrix44::identity()),
		viewProjMatrix(matrix44::identity())
	{
		zShadowDistance = 1000.0f;
	}

	//------------------------------------------------------------------------------
	/**
	*/
	CameraSetting::~CameraSetting()
	{
		//empty
	}
	//------------------------------------------------------------------------------
	/**
	Setup camera as perspective projection. This method can be called
	before or after setting up the object. When the object is alive,
	an update message will be sent to the render-thread.
	*/
	void
		CameraSetting::SetupPerspectiveFovRH(float fov_, float aspect_, float zNear_, float zFar_)
	{
		this->isPersp = true;
		this->zNear   = zNear_;
		this->zFar    = zFar_;
		this->fov     = fov_;
		this->aspect  = aspect_;

		this->projMatrix = matrix44::perspfovrh(this->fov, this->aspect, this->zNear, this->zFar);
		this->invProjMatrix = matrix44::inverse(this->projMatrix);

		float tan_fov = tan(fov_ * 0.5f);
		this->nearHeight = 2.0f * this->zNear * tan_fov;
		this->nearWidth = this->nearHeight * aspect_;

		this->farHeight = 2.0f * this->zFar * tan_fov;
		this->farWidth = this->farHeight * aspect_;


		float yLen = Math::n_tan(0.5f * this->fov);
		float xLen = yLen * this->aspect;
		this->focalLength.set(xLen, yLen);

		this->viewProjDirty = true;
	}

	//------------------------------------------------------------------------------
	/**
	Setup camera as perspective projection with a proj clip plane. 
	This method can be called before or after setting up the object. 
	When the object is alive, an update message will be sent to the
	render-thread.
	*/
	void
		CameraSetting::SetupPerspectiveFovRH(float fov_, float aspect_, float zNear_, float zFar_, float4 clipPlane_, bool reflection)
	{
		float4 plane;

		SetupPerspectiveFovRH(fov_,aspect_,zNear_,zFar_);

		if (reflection)
		{
			plane = clipPlane_;
		}
		else
		{
			plane = float4::transform(matrix44::transpose(matrix44::inverse(this->viewMatrix)), clipPlane_);
		}

		Math::float3 normal = Math::float3(plane.x(), plane.y(), plane.z());
		plane.set_w(plane.w() / normal.normalise());


		float4 vec;
		vec.set_x( (n_sign(plane.x()) + projMatrix.getrow0().z()) / projMatrix.getrow0().x());
		vec.set_y( (n_sign(plane.y()) + projMatrix.getrow1().z()) / projMatrix.getrow1().y());
		vec.set_z(-1.f);
		vec.set_w((1.f + projMatrix.getrow2().z()) / projMatrix.getrow2().w());

		// Calculate the scaled plane vector
		float4 clipPlane4d(plane.x(), plane.y(), plane.z(), plane.w());
		float4 c = clipPlane4d * ( 2.f / (float4::dot4(clipPlane4d,vec)));

#if RENDERDEVICE_D3D9
		projMatrix.setrowcol((c.x() + projMatrix.getrow3().x()) / 2,2,0);
		projMatrix.setrowcol((c.y() + projMatrix.getrow3().y()) / 2,2,1);
		projMatrix.setrowcol((c.z() + 1.f + projMatrix.getrow3().z()) / 2,2,2);
		projMatrix.setrowcol((c.w() + projMatrix.getrow3().w()) / 2, 2,3);
#endif

#if RENDERDEVICE_OPENGL || RENDERDEVICE_OPENGLES
		projMatrix.setrowcol(c.x(),2,0);
		projMatrix.setrowcol(c.y(),2,1);
		projMatrix.setrowcol(c.z() + 1.0f,2,2);
		projMatrix.setrowcol(c.w(),2,3);
#endif	

		UpdateViewFrustum();
	}

	//------------------------------------------------------------------------------
	/**
	Setup camera as orthogonal projection.  This method can be called
	before or after setting up the object. When the object is alive,
	an update message will be sent to the render-thread.
	*/
	void
		CameraSetting::SetupOrthogonal(float w, float h, float zNear_, float zFar_)
	{
		this->isPersp    = false;
		this->zNear      = zNear_;
		this->zFar       = zFar_;
		this->fov        = 0.0f;
		this->aspect     = w / h;
		this->nearWidth  = w;
		this->nearHeight = h;
		this->farWidth   = w;
		this->farHeight  = h;
		this->focalLength.set(1.0f, 1.0f);

		this->projMatrix = matrix44::orthorh(w, h, this->zNear, this->zFar);
		this->invProjMatrix = matrix44::inverse(this->projMatrix);

		this->viewProjDirty = true;
	}

	//------------------------------------------------------------------------------
	/**
	Setup camera as orthogonal projection.  This method can be called
	before or after setting up the object. When the object is alive,
	an update message will be sent to the render-thread.
	*/
	void
		CameraSetting::SetupOffCenterOrthogonal(float l, float r, float b, float t, float zNear_, float zFar_)
	{
		this->isPersp    = false;
		this->zNear      = zNear_;
		this->zFar       = zFar_;
		this->fov        = 0.0f;
		this->aspect     = (r-l) / (t - b);
		this->nearWidth  = r-l;
		this->nearHeight = t - b;
		this->farWidth   = r-l;
		this->farHeight  = t - b;
		this->focalLength.set(1.0f, 1.0f);

		this->projMatrix = matrix44::orthooffcenterrh(l, r, b, t, this->zNear, this->zFar);
		this->invProjMatrix = matrix44::inverse(this->projMatrix);

		this->viewProjDirty = true;
	}

	//------------------------------------------------------------------------------
	/**
	Updates the view-projection matrix.
	*/
	void
		CameraSetting::UpdateViewProjMatrix() const
	{
		n_assert(this->viewProjDirty);
		this->viewProjDirty = false;
		this->viewProjMatrix = matrix44::multiply(this->projMatrix, this->viewMatrix);
	}

	//------------------------------------------------------------------------------
	/**
	*/
	void
		CameraSetting::UpdateViewFrustum() const
	{

		this->viewFrustum.setmatrix(GetViewProjTransform());
		this->viewFrustumDirty = false;
	}

} // namespace Graphic