#include "TCanvas.h"
#include "TH2.h"
#include "TH3.h"
#include "TMarker3DBox.h"
#include "TPolyLine3D.h"
#include "TGLViewer.h"
#include "TView3D.h"
#include "TStyle.h"
#include "TRandom.h"

#include <iostream>
using namespace std;

void proj3d(TH3F *inh3 = NULL)
{
	// Draw 3d hist in a box together with its 2d projections
	// on the walls using TView3D
	// For nicer look one should dive into the features
	// offered by the 3d viewers, especially the TGLViewer
	// Note: This is meant as a guide, no guarantee for correctness
	// 
	// Author: OS
	//
	gStyle->SetCanvasPreferGL(kFALSE);
	auto *c1 = new TCanvas("c1","Project 3d",250,10,800,800);
	TH3F *h3;
	if (inh3 != NULL) {
		h3 = inh3;
	} else {
		// build an example if no TH3 is provided
		h3 = new TH3F("hp33", "3dim ", 40,-4,4, 40,-4,4, 40,-4,4);
		h3->GetXaxis()->SetTitle("px");
		h3->GetYaxis()->SetTitle("py");
		h3->GetZaxis()->SetTitle("pz");
		gRandom->SetSeed();
		Double_t px, py, pz, px1, py1;
		for (Int_t i = 0; i < 1000; i++) {
			gRandom->Rannor(px,py);
			gRandom->Rannor(px1,pz);

			px = 1+ 0.8* px;
			py = -2.5 + 0.4*py;
			pz = -1.5 + 0.2*pz;
			h3->Fill(px, py,pz);
			
			px = -2+ px1;
			py = 2.5 + 0.6*py;
			pz = 1. + 0.25*pz;
			h3->Fill(px, py,pz);
		}
	}
	// draw hist + projections in normal way
	c1->Divide(2,2);
	c1->cd(1);
	h3->Draw("BOX2");
	
	// build projections on planes
	auto projxy = (TH2D*)h3->Project3D("xy");
	auto projyz = (TH2D*)h3->Project3D("yz");
	auto projxz = (TH2D*)h3->Project3D("xz");
	c1->cd(2);
	projxy->Draw("col");
	c1->cd(3);
	projyz->Draw("col");
	c1->cd(4);
	projxz->Draw("col");
	c1->Modified();
	c1->Update();
	
	// now the new part
	gStyle->SetCanvasPreferGL(kTRUE);
	auto *c2 = new TCanvas("c2","Project 3d",600,100,800,800);
	c2->cd();
	Double_t xymin = projxy->GetMinimum();
	Double_t xymax = projxy->GetMaximum();
	Double_t yzmin = projyz->GetMinimum();
	Double_t yzmax = projyz->GetMaximum();
	Double_t xzmin = projxz->GetMinimum();
	Double_t xzmax = projxz->GetMaximum();
	
   TAxis *xa3 = h3->GetXaxis();
   TAxis *ya3 = h3->GetYaxis();
   TAxis *za3 = h3->GetZaxis();
   // assume fixed binwidth
   Double_t xw = 0.5*xa3->GetBinWidth(1);
	Double_t yw = 0.5*ya3->GetBinWidth(1);
	Double_t zw = 0.5*za3->GetBinWidth(1);
   // create view with axis
   Double_t rmin[3], rmax[3];
   // draw the marker boxes just outside the 3d hist volume
   rmin[0] = xa3->GetXmin() - 2 * xw;
   rmin[1] = ya3->GetXmin() - 2 * yw;
   rmin[2] = za3->GetXmin() - 2 * zw;
   rmax[0] = xa3->GetXmax() + 2 * xw;
   rmax[1] = ya3->GetXmax() + 2 * yw;
   rmax[2] = za3->GetXmax() + 2 * zw;

   TView3D *view = new TView3D(1, rmin, rmax);
   view->ShowAxis();
 //  view->Draw("gl");
	TMarker3DBox *pm3d;
	// a box around the scene
	TPolyLine3D *pl3d;
	Double_t xl[5] = {rmin[0], rmax[0], rmax[0], rmin[0], rmin[0]};
	Double_t yl[5] = {rmin[1], rmin[1], rmax[1], rmax[1], rmin[1]};
	Double_t zl[5] = {rmin[2],rmin[2],rmin[2],rmin[2],rmin[2]};
	pl3d = new TPolyLine3D(5, xl, yl, zl);
	pl3d->SetLineColor(1);
	pl3d->SetLineWidth(2);
	pl3d->Draw();
	Double_t xu[5] = {rmin[0], rmax[0], rmax[0], rmin[0], rmin[0]};
	Double_t yu[5] = {rmin[1], rmin[1], rmax[1], rmax[1], rmin[1]};
	Double_t zu[5] = {rmax[2], rmax[2],rmax[2],rmax[2],rmax[2]};
	pl3d = new TPolyLine3D(5, xu, yu, zu);
	pl3d->SetLineColor(1);
	pl3d->SetLineWidth(2);
	pl3d->Draw();
	Double_t xr[2] = {rmax[0], rmax[0]};
	Double_t yr[2] = {rmin[1], rmin[1]};
	Double_t zr[2] = {rmin[2], rmax[2]};
	pl3d = new TPolyLine3D(2, xr, yr, zr);
	pl3d->SetLineColor(1);
	pl3d->SetLineWidth(2);
	pl3d->Draw();
	Double_t xb[2] = {rmax[0], rmax[0]};
	Double_t yb[2] = {rmax[1], rmax[1]};
	Double_t zb[2] = {rmin[2], rmax[2]};
	pl3d = new TPolyLine3D(2, xb, yb, zb);
	pl3d->SetLineColor(1);
	pl3d->SetLineWidth(2);
	pl3d->Draw();
	Double_t xf[2] = {rmin[0], rmin[0]};
	Double_t yf[2] = {rmin[1], rmin[1]};
	Double_t zf[2] = {rmin[2], rmax[2]};
	pl3d = new TPolyLine3D(2, xf, yf, zf);
	pl3d->SetLineColor(1);
	pl3d->SetLineWidth(2);
	pl3d->Draw();
	Double_t xk[2] = {rmin[0], rmin[0]};
	Double_t yk[2] = {rmax[1], rmax[1]};
	Double_t zk[2] = {rmin[2], rmax[2]};
	pl3d = new TPolyLine3D(2, xk, yk, zk);
	pl3d->SetLineColor(1);
	pl3d->SetLineWidth(2);
	pl3d->Draw();
	//
	Int_t ncolors  = gStyle->GetNumberOfColors();
   TAxis *xa = projxy->GetXaxis();
   TAxis *ya = projxy->GetYaxis();

	Double_t xc, yc, zc, bwidth, range;
	// draw xy proj at bottom, fixed z
	zc = za3->GetXmin() - zw;
	// thickness of the boxes
	bwidth = 0.25*zw;
	range = xymax-xymin;
	for(int xb=1; xb<=xa->GetNbins(); xb++) {
		for(int yb=1; yb<=ya->GetNbins(); yb++) {
			int binc = projxy->GetBinContent(xb, yb);
			if (binc > 0) {
				xc = xa->GetBinCenter(xb);
				yc = ya->GetBinCenter(yb);
				pm3d = new TMarker3DBox(yc,xc,zc,yw,xw,bwidth, 0, 0);
				// color number
				int nc = ncolors * binc / range;
				pm3d->SetLineColor(gStyle->GetColorPalette(nc));
				pm3d->SetFillColor(gStyle->GetColorPalette(nc));
				pm3d->SetFillStyle(1);
				pm3d->Draw();
			}
		}
	}
	// draw zy proj at right side, fixed x
	xc = xa3->GetXmax() + xw;
	bwidth = 0.25*xw;
	range = yzmax-yzmin;
	for(int xb=1; xb<=xa->GetNbins(); xb++) {
		for(int yb=1; yb<=ya->GetNbins(); yb++) {
			int binc = projyz->GetBinContent(xb, yb);
			if (binc > 0) {
				yc = xa->GetBinCenter(xb);
				zc = ya->GetBinCenter(yb);
				pm3d = new TMarker3DBox(xc,zc,yc,bwidth,zw,yw, 0, 0);
				// color number
				int nc = ncolors * binc / range;
				pm3d->SetLineColor(gStyle->GetColorPalette(nc));
				pm3d->SetFillColor(gStyle->GetColorPalette(nc));
				pm3d->SetFillStyle(1);
				pm3d->Draw();
			}
		}
	}
	// draw zx proj at back side, fixed y
	yc = ya3->GetXmax() + yw;
	bwidth = 0.25*yw;
	range = xzmax-xzmin;
	for(int xb=1; xb<=xa->GetNbins(); xb++) {
		for(int yb=1; yb<=ya->GetNbins(); yb++) {
			int binc = projxz->GetBinContent(xb, yb);
			if (binc > 0) {
				xc = xa->GetBinCenter(xb);
				zc = ya->GetBinCenter(yb);
				pm3d = new TMarker3DBox(zc,yc,xc,zw,bwidth,xw, 0, 0);
				// color number
				int nc = ncolors * binc / range;
				pm3d->SetLineColor(gStyle->GetColorPalette(nc));
				pm3d->SetFillColor(gStyle->GetColorPalette(nc));
				pm3d->SetFillStyle(1);
				pm3d->Draw();
			}
		}
	}
	// now the 3d hist itself
	range = h3->GetMaximum();
   for(int xb=0; xb<=h3->GetNbinsX(); xb++) {
      for(int yb=0; yb<=h3->GetNbinsY(); yb++) {
         for(int zb=0; zb<=h3->GetNbinsZ(); zb++) {
				int bin = h3->GetBin(xb, yb, zb);
				int binc = h3->GetBinContent(bin);
				if (binc > 0) {
					xc = xa3->GetBinCenter(xb);
					yc = ya3->GetBinCenter(yb);
					zc = za3->GetBinCenter(zb);
					xw = 0.5*xa3->GetBinWidth(xb);
					yw = 0.5*ya3->GetBinWidth(yb);
					zw = 0.5*za3->GetBinWidth(zb);
					pm3d = new TMarker3DBox(xc,yc,zc,xw,yw,zw, 0, 0);
					int nc = ncolors * binc / range;
					pm3d->SetLineColor(gStyle->GetColorPalette(nc));
					pm3d->SetFillColor(gStyle->GetColorPalette(nc));
					pm3d->SetFillStyle(1);
					pm3d->Draw();
				}
			}
		}
	}
	view->Draw();
   TGLViewer *glv = (TGLViewer*)c2->GetViewer3D("ogl");
   cout << "TGLViewer *glv =(TGLViewer*)" << glv << endl;
	glv->DoDraw();
}