/****************************************************************************
* MeshLab                                                           o o     *
* A versatile mesh processing toolbox                             o     o   *
*                                                                _   O  _   *
* Copyright(C) 2005                                                \/)\/    *
* Visual Computing Lab                                            /\/|      *
* ISTI - Italian National Research Council                           |      *
*                                                                    \      *
* All rights reserved.                                                      *
*                                                                           *
* 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 2 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 (http://www.gnu.org/licenses/gpl.txt)          *
* for more details.                                                         *
*                                                                           *
****************************************************************************/

#ifndef SPLATRENDERER_H
#define SPLATRENDERER_H

#include <QObject>
#include <QTextStream>
#include <QFile>
#include <wrap/gl/trimesh.h>
#include <wrap/gl/shaders.h>
#include <wrap/gl/trimesh.h>
#include <QGLFramebufferObject>
#include <vcg/complex/complex.h>
#define GL_TEST_ERR\
	{\
			GLenum eCode;\
			if((eCode=glGetError())!=GL_NO_ERROR)\
					std::cerr << "OpenGL error : " <<  gluErrorString(eCode) << " in " <<  __FILE__ << " : " << __LINE__ << std::endl;\
	}

class QGLFramebufferObject;

/*
	Rendering with Algebraic Point Set Surfaces, by Gael Guennebaud.
	paper: Algebraic Point Set Surfaces SIGGRAPH '07 
*/
template <class MeshType>
class SplatRenderer 
{
	bool mIsSupported;
	bool init_called;

	enum {
		DEFERRED_SHADING_BIT	= 0x000001,
		DEPTH_CORRECTION_BIT	= 0x000002,
		OUTPUT_DEPTH_BIT			= 0x000004,
		BACKFACE_SHADING_BIT	= 0x000008,
		FLOAT_BUFFER_BIT			= 0x000010
	};
	int mFlags;
	int mCachedFlags;
	int mRenderBufferMask;
	int mSupportedMask;

	//int mCurrentPass;
	int mBindedPass;
	GLuint mDummyTexId; // on ATI graphics card we need to bind a texture to get point sprite working !
	bool mWorkaroundATI;
	bool mBuggedAtiBlending;
	GLuint mNormalTextureID;
	GLuint mDepthTextureID;
	ProgramVF mShaders[3];
	QString mShaderSrcs[6];
	QGLFramebufferObject* mRenderBuffer;
	float mCachedMV[16];
	float mCachedProj[16];
	GLint mCachedVP[4];

	struct UniformParameters
	{
		float radiusScale;
		float preComputeRadius;
		float depthOffset;
		float oneOverEwaRadius;
		vcg::Point2f halfVp;
		vcg::Point3f rayCastParameter1;
		vcg::Point3f rayCastParameter2;
		vcg::Point2f depthParameterCast;

		void loadTo(Program& prg);
		void update(float* mv, float* proj, GLint* vp);
	};

	UniformParameters mParams;

	QString loadSource(const QString& func,const QString& file);
	void configureShaders();
	void updateRenderBuffer();
	void enablePass(int n);
	void drawSplats(std::vector<MeshType*> & , vcg::GLW::ColorMode cm,  vcg::GLW::TextureMode tm);
	void drawSplats(
		std::vector< std::vector<vcg::Point3f> *				> & positions,
		std::vector< std::vector<vcg::Point3f> *				> & normals,
		std::vector< std::vector<vcg::Point3<unsigned char> > *	> & colors,
		std::vector<float>  & radius,
		vcg::GLW::ColorMode cm,  vcg::GLW::TextureMode tm);
	

public:

	void Clear();
	void Destroy();
	bool isSupported() {return mIsSupported;}
	void Init(QGLWidget *gla);
	void Render( std::vector<MeshType*> &meshes,  vcg::GLW::ColorMode cm,  vcg::GLW::TextureMode tm);

	void Render(
		std::vector< std::vector<vcg::Point3f> *				> & positions,
		std::vector< std::vector<vcg::Point3f> *				> & normals,
		std::vector< std::vector<vcg::Point3<unsigned char> > *	> & colors,
		std::vector<float>  & radius,
		vcg::GLW::ColorMode cm,  vcg::GLW::TextureMode tm);

};// end class

template <class MeshType>
void SplatRenderer<MeshType>:: Destroy(){
	delete mRenderBuffer; 
	mRenderBuffer = 0;
	glDeleteTextures(1,&mDepthTextureID);
	glDeleteTextures(1,&mNormalTextureID);
	for(int i = 0; i < 3; ++i)
		this->mShaders[i].prog.Del();

	Clear();
}

template <class MeshType>
void SplatRenderer<MeshType>::Clear()
{
	mNormalTextureID = 0;
	mDepthTextureID = 0;
	mIsSupported = false;
	mRenderBuffer = 0;
	mWorkaroundATI = false;
	mBuggedAtiBlending = false;
	mDummyTexId = 0;

	mFlags = DEFERRED_SHADING_BIT | DEPTH_CORRECTION_BIT | FLOAT_BUFFER_BIT | OUTPUT_DEPTH_BIT;
	mCachedFlags = ~mFlags;
	// union of bits which controls the render buffer
	mRenderBufferMask = DEFERRED_SHADING_BIT | FLOAT_BUFFER_BIT;

	init_called = false;
}


template <class MeshType>
QString SplatRenderer<MeshType>::loadSource(const QString& func,const QString& filename)
{
	QString res;
	QFile f(":/SplatRenderer/shaders/" + filename);
	if (!f.open(QFile::ReadOnly))
	{
		std::cerr << "failed to load shader file " << filename.toUtf8().data() << "\n";
		return res;
	}
	else qDebug("Succesfully loaded shader func '%s' in file '%s'",qPrintable(func),qPrintable(filename));
	QTextStream stream(&f);
	res = stream.readAll();
	f.close();
	res = QString("#define __%1__ 1\n").arg(func)
			+ QString("#define %1 main\n").arg(func)
			+ res;
	return res;
}
template <class MeshType>
void SplatRenderer<MeshType>::configureShaders()
{
	const char* passNames[3] = {"Visibility","Attribute","Finalization"};
	QString defines = "";
	if (mFlags & DEFERRED_SHADING_BIT)
		defines += "#define EXPE_DEFERRED_SHADING\n";
	if (mFlags & DEPTH_CORRECTION_BIT)
		defines += "#define EXPE_DEPTH_CORRECTION\n";
	if (mFlags & OUTPUT_DEPTH_BIT)
		defines += "#define EXPE_OUTPUT_DEPTH 1\n";
	if (mFlags & BACKFACE_SHADING_BIT)
		defines += "#define EXPE_BACKFACE_SHADING\n";
	if (mWorkaroundATI)
		defines += "#define EXPE_ATI_WORKAROUND\n";

	QString shading =
"vec4 meshlabLighting(vec4 color, vec3 eyePos, vec3 normal)"
"{"
"	normal = normalize(normal);"
"	vec3 lightVec = normalize(gl_LightSource[0].position.xyz);"
"	vec3 halfVec = normalize( lightVec - normalize(eyePos) );"
"	float aux_dot = dot(normal,lightVec);"
"	float diffuseCoeff = clamp(aux_dot, 0.0, 1.0);"
" float specularCoeff = aux_dot>0.0 ? clamp(pow(clamp(dot(halfVec, normal),0.0,1.0),gl_FrontMaterial.shininess), 0.0, 1.0) : 0.0;"
"	return vec4(color.rgb * ( gl_FrontLightProduct[0].ambient.rgb + diffuseCoeff * gl_FrontLightProduct[0].diffuse.rgb) + specularCoeff * gl_FrontLightProduct[0].specular.rgb, 1.0);"
"}\n";

	for (int k=0;k<3;++k)
	{
		QString vsrc = shading + defines + mShaderSrcs[k*2+0];
		QString fsrc = shading + defines + mShaderSrcs[k*2+1];
		mShaders[k].SetSources(mShaderSrcs[k*2+0]!="" ? vsrc.toUtf8().data() : 0,
													 mShaderSrcs[k*2+1]!="" ? fsrc.toUtf8().data() : 0);
		mShaders[k].prog.Link();
		if (mShaderSrcs[k*2+0]!="")
		{
			std::string compileinfo = mShaders[k].vshd.InfoLog();
			if (compileinfo.size()>0)
				std::cout << "Vertex shader info (" << passNames[k] << ":\n" << compileinfo << "\n";
		}
		if (mShaderSrcs[k*2+1]!="")
		{
			std::string compileinfo = mShaders[k].fshd.InfoLog();
			if (compileinfo.size()>0)
				std::cout << "Fragment shader info (" << passNames[k] << ":\n" << compileinfo << "\n";
		}
		std::string linkinfo = mShaders[k].prog.InfoLog();
		if (linkinfo.size()>0)
			std::cout << "Link info (" << passNames[k] << ":\n" << linkinfo << "\n";
	}
}

template <class MeshType>
void SplatRenderer<MeshType>::Init(QGLWidget *gla)
{

	mIsSupported = true;
	gla->makeCurrent();
	// FIXME this should be done in meshlab !!! ??
	glewInit();

	const char* rs = (const char*)glGetString(GL_RENDERER);
	QString rendererString("");
	if(rs)
		rendererString = QString(rs);
	mWorkaroundATI = rendererString.startsWith("ATI") || rendererString.startsWith("AMD");
	// FIXME: maybe some recent HW correctly supports floating point blending...
	mBuggedAtiBlending = rendererString.startsWith("ATI") || rendererString.startsWith("AMD");

	if (mWorkaroundATI && mDummyTexId==0)
	{
		glActiveTexture(GL_TEXTURE0);
		glGenTextures(1,&mDummyTexId);
		glBindTexture(GL_TEXTURE_2D, mDummyTexId);
		glTexImage2D(GL_TEXTURE_2D, 0, GL_LUMINANCE, 4, 4, 0, GL_LUMINANCE, GL_UNSIGNED_BYTE, 0);
	}

	// let's check the GPU capabilities
	mSupportedMask = DEPTH_CORRECTION_BIT | BACKFACE_SHADING_BIT;
	if (!QGLFramebufferObject::hasOpenGLFramebufferObjects ())
	{
		mIsSupported = false;
		return;
	}
	if (GLEW_ARB_texture_float)
		mSupportedMask |= FLOAT_BUFFER_BIT;
	else
		std::cout << "Splatting: warning floating point textures are not supported.\n";

	if (GLEW_ARB_draw_buffers && (!mBuggedAtiBlending))
		mSupportedMask |= DEFERRED_SHADING_BIT;
	else
		std::cout << "Splatting: warning deferred shading is not supported.\n";

	if (GLEW_ARB_shadow)
		mSupportedMask |= OUTPUT_DEPTH_BIT;
	else
		std::cerr << "Splatting: warning copy of the depth buffer is not supported.\n";

	mFlags = mFlags & mSupportedMask;

	// load shader source
	mShaderSrcs[0] = loadSource("VisibilityVP","Raycasting.glsl");
	mShaderSrcs[1] = loadSource("VisibilityFP","Raycasting.glsl");
	mShaderSrcs[2] = loadSource("AttributeVP","Raycasting.glsl");
	mShaderSrcs[3] = loadSource("AttributeFP","Raycasting.glsl");
	mShaderSrcs[4] = "";
	mShaderSrcs[5] = loadSource("Finalization","Finalization.glsl");

	//mCurrentPass = 2;
	mBindedPass = -1;
	GL_TEST_ERR
}

template <class MeshType>
void SplatRenderer<MeshType>::updateRenderBuffer()
{
	if ( (!mRenderBuffer)
		|| (mRenderBuffer->width()!=mCachedVP[2])
		|| (mRenderBuffer->height()!=mCachedVP[3])
		|| ( (mCachedFlags & mRenderBufferMask) != (mFlags & mRenderBufferMask) ))
	{
		delete mRenderBuffer;
		GLenum fmt = (mFlags&FLOAT_BUFFER_BIT) ? GL_RGBA16F_ARB : GL_RGBA;
		mRenderBuffer = new QGLFramebufferObject(mCachedVP[2], mCachedVP[3],
				(mFlags&OUTPUT_DEPTH_BIT) ? QGLFramebufferObject::NoAttachment : QGLFramebufferObject::Depth,
				GL_TEXTURE_RECTANGLE_ARB, fmt);

		if (!mRenderBuffer->isValid())
		{
			std::cout << "SplatRenderer: invalid FBO\n";
		}

		GL_TEST_ERR
		if (mFlags&DEFERRED_SHADING_BIT)
		{
			// in deferred shading mode we need an additional buffer to accumulate the normals
			if (mNormalTextureID==0)
				glGenTextures(1,&mNormalTextureID);
			glBindTexture(GL_TEXTURE_RECTANGLE_ARB, mNormalTextureID);
			glTexImage2D(GL_TEXTURE_RECTANGLE_ARB, 0, fmt, mCachedVP[2], mCachedVP[3], 0, GL_RGBA, GL_FLOAT, 0);
			glTexParameteri(GL_TEXTURE_RECTANGLE_ARB, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
			glTexParameteri(GL_TEXTURE_RECTANGLE_ARB, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
			mRenderBuffer->bind();
			glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT1_EXT, GL_TEXTURE_RECTANGLE_ARB, mNormalTextureID, 0);
			mRenderBuffer->release();
			GL_TEST_ERR
		}

		if (mFlags&OUTPUT_DEPTH_BIT)
		{
			// to output the depth values to the final depth buffer we need to
			// attach a depth buffer as a texture
			if (mDepthTextureID==0)
				glGenTextures(1,&mDepthTextureID);
			glBindTexture(GL_TEXTURE_RECTANGLE_ARB, mDepthTextureID);
			glTexImage2D(GL_TEXTURE_RECTANGLE_ARB, 0, GL_DEPTH_COMPONENT24_ARB, mCachedVP[2], mCachedVP[3], 0, GL_DEPTH_COMPONENT, GL_FLOAT, 0);
			glTexParameteri(GL_TEXTURE_RECTANGLE_ARB, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
			glTexParameteri(GL_TEXTURE_RECTANGLE_ARB, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
			mRenderBuffer->bind();
			glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT, GL_DEPTH_ATTACHMENT_EXT, GL_TEXTURE_RECTANGLE_ARB, mDepthTextureID, 0);
			mRenderBuffer->release();
			GL_TEST_ERR
		}
	}
}


template <class MeshType>
void SplatRenderer<MeshType>::Render(std::vector<MeshType*> & meshes,  vcg::GLW::ColorMode cm,  vcg::GLW::TextureMode tm )
{
	if(meshes.empty()) return;

	GL_TEST_ERR

		/*************** First Pass ***********/
		// this is the first pass of the frame, so let's update the shaders, buffers, etc...
		glGetIntegerv(GL_VIEWPORT, mCachedVP);
		glGetFloatv(GL_MODELVIEW_MATRIX, mCachedMV);
		glGetFloatv(GL_PROJECTION_MATRIX, mCachedProj);

		updateRenderBuffer();
		if (mCachedFlags != mFlags)
			configureShaders();

		mCachedFlags = mFlags;

		mParams.update(mCachedMV, mCachedProj, mCachedVP);
		//float s = meshes[0]->glw.GetHintParamf(vcg::GLW::HNPPointSize);
		//if (s>1)
		//	s = pow(s,0.3f);
		float s = 1.f;
		mParams.radiusScale *= s;

		// FIXME since meshlab does not set any material properties, let's define some here
		glDisable(GL_COLOR_MATERIAL);
		glMaterialf(GL_FRONT_AND_BACK, GL_SHININESS, 64);
		glMaterialfv(GL_FRONT_AND_BACK, GL_AMBIENT, vcg::Point4f(0.3, 0.3, 0.3, 1.).V());
		glMaterialfv(GL_FRONT_AND_BACK, GL_DIFFUSE, vcg::Point4f(0.6, 0.6, 0.6, 1.).V());
		glMaterialfv(GL_FRONT_AND_BACK, GL_SPECULAR, vcg::Point4f(0.5, 0.5, 0.5, 1.).V());

		mRenderBuffer->bind();
		if (mFlags&DEFERRED_SHADING_BIT)
		{
			GLenum buf[2] = {GL_COLOR_ATTACHMENT0_EXT,GL_COLOR_ATTACHMENT1_EXT};
			glDrawBuffersARB(2, buf);
		}
		glViewport(mCachedVP[0],mCachedVP[1],mCachedVP[2],mCachedVP[3]);
		glClearColor(0,0,0,0);
		glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
		
		//* End Setup of first Pass Now a simple rendering of all the involved meshes.*/ 
		mParams.loadTo(mShaders[0].prog);
		enablePass(0);
		drawSplats(meshes,cm,tm);

		// begin second pass 
		mParams.loadTo(mShaders[1].prog);
		enablePass(1);

		drawSplats(meshes,cm,tm);
		
		//* Start third Pass Setup */ 

		// this is the last pass: normalization by the sum of weights + deferred shading
		mRenderBuffer->release();
		if (mFlags&DEFERRED_SHADING_BIT)
			glDrawBuffer(GL_BACK);

		enablePass(2);

		// switch to normalized 2D rendering mode
		glMatrixMode(GL_PROJECTION);
		glPushMatrix();
		glLoadIdentity();
		glMatrixMode(GL_MODELVIEW);
		glPushMatrix();
		glLoadIdentity();

		mShaders[2].prog.Uniform("viewport",float(mCachedVP[0]),float(mCachedVP[1]),float(mCachedVP[2]),float(mCachedVP[3]));
		mShaders[2].prog.Uniform("ColorWeight",GLint(0)); // this is a texture unit
		glActiveTexture(GL_TEXTURE0);
		glBindTexture(GL_TEXTURE_RECTANGLE_ARB,mRenderBuffer->texture());

		if (mFlags&DEFERRED_SHADING_BIT)
		{
			mShaders[2].prog.Uniform("unproj", mCachedProj[10], mCachedProj[14]);
			mShaders[2].prog.Uniform("NormalWeight",GLint(1)); // this is a texture unit
			glActiveTexture(GL_TEXTURE1);
			glBindTexture(GL_TEXTURE_RECTANGLE_ARB,mNormalTextureID);
			GL_TEST_ERR
		}

		if (mFlags&OUTPUT_DEPTH_BIT)
		{
			mShaders[2].prog.Uniform("Depth",GLint(2)); // this is a texture unit
			glActiveTexture(GL_TEXTURE2);GL_TEST_ERR
			glBindTexture(GL_TEXTURE_RECTANGLE_ARB,mDepthTextureID);GL_TEST_ERR
			GL_TEST_ERR
		}
		else
		{
			glDisable(GL_DEPTH_TEST);
			glDepthMask(GL_FALSE);
		}

		// draw a quad covering the whole screen
    vcg::Point3f viewVec(1./mCachedProj[0], 1./mCachedProj[5], -1);

    glBegin(GL_QUADS);
			glColor3f(1, 0, 0);
			glTexCoord3f(viewVec.X(),viewVec.Y(),viewVec.Z());
			glMultiTexCoord2f(GL_TEXTURE1,1.,1.);
			glVertex3f(1,1,0);

			glColor3f(1, 1, 0);
			glTexCoord3f(-viewVec.X(),viewVec.Y(),viewVec.Z());
			glMultiTexCoord2f(GL_TEXTURE1,0.,1.);
			glVertex3f(-1,1,0);

			glColor3f(0, 1, 1);
			glTexCoord3f(-viewVec.X(),-viewVec.Y(),viewVec.Z());
			glMultiTexCoord2f(GL_TEXTURE1,0.,0.);
			glVertex3f(-1,-1,0);

			glColor3f(1, 0, 1);
			glTexCoord3f(viewVec.X(),-viewVec.Y(),viewVec.Z());
			glMultiTexCoord2f(GL_TEXTURE1,1.,0.);
			glVertex3f(1,-1,0);
    glEnd();
    if (!(mFlags&OUTPUT_DEPTH_BIT))
    {
        glEnable(GL_DEPTH_TEST);
        glDepthMask(GL_TRUE);
    }

		glUseProgram(0);

		// restore matrices
		glMatrixMode(GL_PROJECTION);
		glPopMatrix();
		glMatrixMode(GL_MODELVIEW);
		glPopMatrix();
		
	  GL_TEST_ERR

}


template <class MeshType>
void SplatRenderer<MeshType>::Render(
		std::vector< std::vector<vcg::Point3f> *				> & positions,
		std::vector< std::vector<vcg::Point3f> *				> & normals,
		std::vector< std::vector<vcg::Point3<unsigned char> > *	> & colors,
		std::vector<float>  & radius,  vcg::GLW::ColorMode cm,  vcg::GLW::TextureMode tm )
{
	if(positions.empty()) return;

	GL_TEST_ERR

		/*************** First Pass ***********/
		// this is the first pass of the frame, so let's update the shaders, buffers, etc...
		glGetIntegerv(GL_VIEWPORT, mCachedVP);
		glGetFloatv(GL_MODELVIEW_MATRIX, mCachedMV);
		glGetFloatv(GL_PROJECTION_MATRIX, mCachedProj);

		updateRenderBuffer();
		if (mCachedFlags != mFlags)
			configureShaders();

		mCachedFlags = mFlags;

		mParams.update(mCachedMV, mCachedProj, mCachedVP);
		//float s = meshes[0]->glw.GetHintParamf(vcg::GLW::HNPPointSize);
		//if (s>1)
		//	s = pow(s,0.3f);
		float s = 1.f;
		mParams.radiusScale *= s;

		// FIXME since meshlab does not set any material properties, let's define some here
		glDisable(GL_COLOR_MATERIAL);
		glMaterialf(GL_FRONT_AND_BACK, GL_SHININESS, 64);
		glMaterialfv(GL_FRONT_AND_BACK, GL_AMBIENT, vcg::Point4f(0.3, 0.3, 0.3, 1.).V());
		glMaterialfv(GL_FRONT_AND_BACK, GL_DIFFUSE, vcg::Point4f(0.6, 0.6, 0.6, 1.).V());
		glMaterialfv(GL_FRONT_AND_BACK, GL_SPECULAR, vcg::Point4f(0.5, 0.5, 0.5, 1.).V());

		mRenderBuffer->bind();
		if (mFlags&DEFERRED_SHADING_BIT)
		{
			GLenum buf[2] = {GL_COLOR_ATTACHMENT0_EXT,GL_COLOR_ATTACHMENT1_EXT};
			glDrawBuffersARB(2, buf);
		}
		glViewport(mCachedVP[0],mCachedVP[1],mCachedVP[2],mCachedVP[3]);
		glClearColor(0,0,0,0);
		glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
		
		//* End Setup of first Pass Now a simple rendering of all the involved meshes.*/ 
		mParams.loadTo(mShaders[0].prog);
		enablePass(0);
		drawSplats(positions,normals,colors,radius,cm,tm);

		// begin second pass 
		mParams.loadTo(mShaders[1].prog);
		enablePass(1);

		drawSplats(positions,normals,colors,radius,cm,tm);
		
		//* Start third Pass Setup */ 

		// this is the last pass: normalization by the sum of weights + deferred shading
		mRenderBuffer->release();
		if (mFlags&DEFERRED_SHADING_BIT)
			glDrawBuffer(GL_BACK);

		enablePass(2);

		// switch to normalized 2D rendering mode
		glMatrixMode(GL_PROJECTION);
		glPushMatrix();
		glLoadIdentity();
		glMatrixMode(GL_MODELVIEW);
		glPushMatrix();
		glLoadIdentity();

		mShaders[2].prog.Uniform("viewport",float(mCachedVP[0]),float(mCachedVP[1]),float(mCachedVP[2]),float(mCachedVP[3]));
		mShaders[2].prog.Uniform("ColorWeight",GLint(0)); // this is a texture unit
		glActiveTexture(GL_TEXTURE0);
		glBindTexture(GL_TEXTURE_RECTANGLE_ARB,mRenderBuffer->texture());

		if (mFlags&DEFERRED_SHADING_BIT)
		{
			mShaders[2].prog.Uniform("unproj", mCachedProj[10], mCachedProj[14]);
			mShaders[2].prog.Uniform("NormalWeight",GLint(1)); // this is a texture unit
			glActiveTexture(GL_TEXTURE1);
			glBindTexture(GL_TEXTURE_RECTANGLE_ARB,mNormalTextureID);
			GL_TEST_ERR
		}

		if (mFlags&OUTPUT_DEPTH_BIT)
		{
			mShaders[2].prog.Uniform("Depth",GLint(2)); // this is a texture unit
			glActiveTexture(GL_TEXTURE2);GL_TEST_ERR
			glBindTexture(GL_TEXTURE_RECTANGLE_ARB,mDepthTextureID);GL_TEST_ERR
			GL_TEST_ERR
		}
		else
		{
			glDisable(GL_DEPTH_TEST);
			glDepthMask(GL_FALSE);
		}

		// draw a quad covering the whole screen
    vcg::Point3f viewVec(1./mCachedProj[0], 1./mCachedProj[5], -1);

    glBegin(GL_QUADS);
			glColor3f(1, 0, 0);
			glTexCoord3f(viewVec.X(),viewVec.Y(),viewVec.Z());
			glMultiTexCoord2f(GL_TEXTURE1,1.,1.);
			glVertex3f(1,1,0);

			glColor3f(1, 1, 0);
			glTexCoord3f(-viewVec.X(),viewVec.Y(),viewVec.Z());
			glMultiTexCoord2f(GL_TEXTURE1,0.,1.);
			glVertex3f(-1,1,0);

			glColor3f(0, 1, 1);
			glTexCoord3f(-viewVec.X(),-viewVec.Y(),viewVec.Z());
			glMultiTexCoord2f(GL_TEXTURE1,0.,0.);
			glVertex3f(-1,-1,0);

			glColor3f(1, 0, 1);
			glTexCoord3f(viewVec.X(),-viewVec.Y(),viewVec.Z());
			glMultiTexCoord2f(GL_TEXTURE1,1.,0.);
			glVertex3f(1,-1,0);
    glEnd();
    if (!(mFlags&OUTPUT_DEPTH_BIT))
    {
        glEnable(GL_DEPTH_TEST);
        glDepthMask(GL_TRUE);
    }

		glUseProgram(0);

		// restore matrices
		glMatrixMode(GL_PROJECTION);
		glPopMatrix();
		glMatrixMode(GL_MODELVIEW);
		glPopMatrix();
		
	  GL_TEST_ERR

}
#if 0
void SplatRenderer::Draw(QAction *a, MeshModel &m, RenderMode &rm, QGLWidget * gla)
{
	if (m.vert.RadiusEnabled)
	{
		if (mCurrentPass==2)
			return;

		enablePass(mCurrentPass);
		/*if (mCurrentPass==1)*/ drawSplats(m, rm);
	}
	else if (mCurrentPass==2)
	{
		MeshRenderInterface::Draw(a, m, rm, gla);
	}
}
#endif
template <class MeshType>
void SplatRenderer<MeshType>::enablePass(int n)
{
	if (mBindedPass!=n)
	{
		if (mBindedPass>=0)
			mShaders[mBindedPass].prog.Unbind();
		mShaders[n].prog.Bind();
		mBindedPass = n;

		// set GL states
		if (n==0)
		{
			glDisable(GL_LIGHTING);
// 			glDisable(GL_POINT_SMOOTH);
			glEnable(GL_VERTEX_PROGRAM_POINT_SIZE);

			glAlphaFunc(GL_LESS,1);
			glColorMask(GL_FALSE,GL_FALSE,GL_FALSE,GL_FALSE);
			glDepthMask(GL_TRUE);
			glDisable(GL_BLEND);
			glEnable(GL_ALPHA_TEST);
			glEnable(GL_DEPTH_TEST);

// 			glActiveTexture(GL_TEXTURE0);
// 			glTexEnvf(GL_POINT_SPRITE, GL_COORD_REPLACE, GL_TRUE);
// 			glEnable(GL_POINT_SPRITE_ARB);
		}
		if (n==1)
		{
			glDisable(GL_LIGHTING);
			glEnable(GL_POINT_SMOOTH);
			glActiveTexture(GL_TEXTURE0);
			glEnable(GL_VERTEX_PROGRAM_POINT_SIZE);

			glColorMask(GL_TRUE,GL_TRUE,GL_TRUE,GL_TRUE);
			glBlendFuncSeparate(GL_SRC_ALPHA, GL_ONE, GL_ONE,GL_ONE);
// 			//glBlendFuncSeparate(GL_ONE, GL_ZERO, GL_ONE,GL_ZERO);
// 			glBlendFunc(GL_ONE,GL_ZERO);
			glDepthMask(GL_FALSE);
			glEnable(GL_BLEND);
			glEnable(GL_DEPTH_TEST);
			glDisable(GL_ALPHA_TEST);

// 			glActiveTexture(GL_TEXTURE0);

		}
		if ( (n==0) || (n==1) )
		{
			// enable point sprite rendering mode
			glActiveTexture(GL_TEXTURE0);
			if (mWorkaroundATI)
			{
				glBindTexture(GL_TEXTURE_2D, mDummyTexId);
				glTexImage2D(GL_TEXTURE_2D, 0, GL_LUMINANCE, 2, 2, 0, GL_LUMINANCE, GL_UNSIGNED_BYTE, 0);
				glPointParameterf(GL_POINT_SPRITE_COORD_ORIGIN, GL_LOWER_LEFT);
				// hm... ^^^^
			}
			glTexEnvf(GL_POINT_SPRITE, GL_COORD_REPLACE, GL_TRUE);
			glEnable(GL_POINT_SPRITE_ARB);
		}
		if (n==2)
		{
			glColorMask(GL_TRUE,GL_TRUE,GL_TRUE,GL_TRUE);
			glDepthMask(GL_TRUE);
			glDisable(GL_LIGHTING);
			glDisable(GL_BLEND);
		}
	}
}


template <class MeshType>
void SplatRenderer<MeshType>::drawSplats(
		std::vector< std::vector<vcg::Point3f> *				> & positions,
		std::vector< std::vector<vcg::Point3f> *				> & normals,
		std::vector< std::vector<vcg::Point3<unsigned char> > *	> & colors,
		std::vector<float>  & radius,
		vcg::GLW::ColorMode cm,  vcg::GLW::TextureMode tm)
{
	for(unsigned int ii = 0; ii < positions.size();++ii)
		{

			glBegin(GL_POINTS);
			glMultiTexCoord1f(GL_TEXTURE2, radius[ii] );

			for(unsigned int  vi= 0;vi<  positions[ii]->size() ;++vi){
				vcg::Point3<unsigned char> co = (*colors[ii])[vi];
					glColor3ub ( co[0],co[1],co[2]);
					glNormal((*normals[ii])[vi]);
					glVertex( (*positions[ii])[vi]);
				}
			glEnd();
	}
}


template <class MeshType>
void SplatRenderer<MeshType>::drawSplats(std::vector<MeshType*> & meshes, vcg::GLW::ColorMode cm,  vcg::GLW::TextureMode tm)
{

	// check if we have to use the immediate mode
	if(meshes.empty()) return;
	int nV = 0;

	/* temporary patch: If the number of vertices is above IMMEDIATE_MODE_THR,
		use the immediate mode
	*/
	const int IMMEDIATE_MODE_THR = 0;

	unsigned int ii = 0;
	for(; ii < meshes.size();++ii){
		nV+=meshes[ii]->vn;
		if((nV>IMMEDIATE_MODE_THR) || (meshes[ii]->vn!=(int) meshes[ii]->vert.size()))
			break; 
	}
	bool immediatemode =  ii<meshes.size() ;


	if(immediatemode){
		for(unsigned int ii = 0; ii < meshes.size();++ii)
			{
			MeshType & m = *meshes[ii];
			// immediate mode
			 
			if( (cm == vcg::GLW::CMPerFace)  && (!vcg::tri::HasPerFaceColor( m)) )
				cm=vcg::GLW::CMNone;
			glPushMatrix();
			glMultMatrix( m.Tr);
                        typename MeshType::VertexIterator vi;
			glBegin(GL_POINTS);
				if(cm==vcg::GLW::CMPerMesh)
					glColor( m.C());


				for(vi= m.vert.begin();vi!= m.vert.end();++vi)
					if(!(*vi).IsD())
					{
						glMultiTexCoord1f(GL_TEXTURE2, (*vi).cR());
						glNormal((*vi).cN());
						if (cm==vcg::GLW::CMPerVert) glColor((*vi).C());
						glVertex((*vi).P());
					}
			glEnd();
			glPopMatrix();
			
		}
		return;
	}

		for(unsigned int ii = 0; ii < meshes.size();++ii){
			MeshType & m = *meshes[ii];
			// bind the radius
			glClientActiveTexture(GL_TEXTURE2);
			glTexCoordPointer(
				1,
				GL_FLOAT,
				size_t(&m.vert[1].R())-size_t(&m.vert[0].R()),
				&m.vert[0].R()
			);
			glEnableClientState(GL_TEXTURE_COORD_ARRAY);
			glClientActiveTexture(GL_TEXTURE0);

			// draw the vertices
			vcg::GlTrimesh<MeshType> glw;
			glw.m = &m;
			glw.Draw(vcg::GLW::DMPoints,cm,tm);

			glClientActiveTexture(GL_TEXTURE2);
			glDisableClientState(GL_TEXTURE_COORD_ARRAY);
			glClientActiveTexture(GL_TEXTURE0);
		}
}

template <class MeshType>
void SplatRenderer<MeshType>::UniformParameters::update(float* mv, float* proj, GLint* vp)
{
	// extract the uniform scale
	float scale = vcg::Point3f(mv[0],mv[1],mv[2]).Norm();

	radiusScale = scale;
	preComputeRadius = - std::max(proj[0]*vp[2], proj[5]*vp[3]);
	depthOffset = 2.0;
	oneOverEwaRadius = 0.70710678118654;
	halfVp = vcg::Point2f(0.5*vp[2], 0.5*vp[3]);
	rayCastParameter1 =vcg::Point3f(2./(proj[0]*vp[2]), 2./(proj[5]*vp[3]), 0.0);
	rayCastParameter2 =vcg::Point3f(-1./proj[0], -1./proj[5], -1.0);
	depthParameterCast = vcg::Point2f(0.5*proj[14], 0.5-0.5*proj[10]);
}
template <class MeshType>
void SplatRenderer <MeshType>::UniformParameters::loadTo(Program& prg)
{
	prg.Bind();
	prg.Uniform("expeRadiusScale",radiusScale);
	prg.Uniform("expePreComputeRadius",preComputeRadius);
	prg.Uniform("expeDepthOffset",depthOffset);
	prg.Uniform("oneOverEwaRadius",oneOverEwaRadius);
	prg.Uniform("halfVp",halfVp);
	prg.Uniform("rayCastParameter1",rayCastParameter1);
	prg.Uniform("rayCastParameter2",rayCastParameter2);
	prg.Uniform("depthParameterCast",depthParameterCast);
}

#endif