I am trying to load freetype chars, stuff them into a texture as subimages and then render them instanced.
While most of it seems to work, right now I have a problem with storing the texture coordinates into a glm::mat2x4 matrix.
As can be seen below each character has a struct with information I right now deem necessary, including a matrix called face, which should store the texture coordinates.
But when it comes to assigning the coordinates, after leaving the loop in which it takes place, suddenly all the values go crazy, without any (wanted/ intended) operation taking place from my side.
After creating the texture atlas with freetype and putting all my structs into the map, I assign the width and height of my texture aw & ah to a storage class called c_atlas.
I calculate the texture coordinates in the loop shown below, make the glm::mat2x4 a 0.0f matrix and then stuff them into it. Couting them into the console gives the values I want.
After leaving the for loop I start another one, browsing over the matrix and cout them into the console, which gives me more or less random values in the range of e^-23 to e^32.
All of this happens in namespace foo and is called in a constructor of a class in the same namespace (sth. like this:)
foo::class::constructor()
{
call_function();
}
int main()
{
foo::class c;
c.call_function();
}
I crafted a minimum working example, but unfortunatly I am not able to replicate the error.
So I have the following loop running (a part of call_function():
namespace foo
{
namespace alphabet
{
const char path_arial[] = "res/font/consola.ttf";
class character
{
public:
glm::vec2 advance;
glm::vec2 bearing;
glm::vec2 size;
glm::vec2 offset;
glm::mat2x4 face;
};
std::map<char, character> char_map;
FT_Library m_ftlib;
FT_Face m_ftface;
GLuint m_VBO, m_VAO;
}
c_atlas ascii;
}
void foo::call_function()
{
//creating all the charactur structs with freetype and store them in the char_map
std::ofstream f("atlas_data.csv", std::ios::openmode::_S_app);
f << "letter;topleft.x;topleft.y;topright.x;topright.y;bottomright.x;bottomright.y;bottomleft.x;bottomleft.y" << std::endl;
for(auto c : alphabet::char_map)
{
std::cout << "b4: " << c.second.offset.x;
c.second.offset /= glm::vec2(aw,ah);
std::cout << "\nafter: " << c.second.offset.x << std::endl;
glm::vec2 ts = c.second.size/glm::vec2(aw,ah);
//couts the right values
uint16_t n = 0;
c.second.face = glm::mat2x4(0.0f);
for(uint16_t i = 0; i < 4; ++i)
{
std::cout << c.first << " at init:\n";
std::cout << c.second.face[0][i] << "\n";
std::cout << c.second.face[1][i] << std::endl;
}
//couts the right values
c.second.face[0][n++] = c.second.offset.x;
c.second.face[0][n++] = c.second.offset.y;
c.second.face[0][n++] = c.second.offset.x+ts.x;
c.second.face[0][n++] = c.second.offset.y;
n = 0;
c.second.face[1][n++]= c.second.offset.x+ts.x;
c.second.face[1][n++] = c.second.offset.y+ts.y;
c.second.face[1][n++] = c.second.offset.x;
c.second.face[1][n++]= c.second.offset.y+ts.y;
for(uint16_t i = 0; i < 4; ++i)
{
std::cout << c.first << " assigned:\n";
std::cout << c.second.face[0][i] << "\n";
std::cout << c.second.face[1][i] << std::endl;
}
//still couts the right values
f << (char)c.first << ";" << c.second.face[0].x << ";" << c.second.face[0].y << ";" << c.second.face[0].z << ";" << c.second.face[0].w << ";" << c.second.face[1].x << ";" << c.second.face[1].y << ";" << c.second.face[1].z << ";" << c.second.face[1].w << std::endl;
//the file also have the right values
}
f.close();
glPixelStorei(GL_UNPACK_ALIGNMENT, 4);
//yet here all the values totally off track, i.e. e^32 or e^-23 (while they should all be between 0.01f - 1.0f)
for(auto i : alphabet::char_map)
{
std::cout << "\ntopleft:\n";
std::cout << "X: " << i.second.face[0].x << " | " << "Y: " << i.second.face[0].x;
std::cout << "\ntopright:\n";
std::cout << "X: " << i.second.face[0].z << " | " << "Y: " << i.second.face[0].w;
std::cout << "\nbotleft:\n";
std::cout << "X: " << i.second.face[1].x << " | " << "Y: " << i.second.face[1].x;
std::cout << "\nbotright:\n";
std::cout << "X: " << i.second.face[1].z << " | " << "Y: " << i.second.face[1].w;
}
}
my mwe:
#include <iostream>
#include <string>
#include "glm/glm.hpp"
#include "GL/gl.h"
#include <map>
struct bin
{
glm::mat2x4 mat;
};
int main( int argc, char *argv[] )
{
std::map<char, bin> bucket;
uint16_t r = 0;
for(uint16_t n = 0; n < 7; ++n)
{
glm::vec4 v = glm::vec4(0.12128f, 0.12412f, 0.15532f, 0.23453f);
bin b;
r = 0;
b.mat[0][r++] = v.x;
b.mat[0][r++] = v.y;
b.mat[0][r++] = v.z;
b.mat[0][r++] = v.w;
r = 0;
b.mat[1][r++] = v.x;
b.mat[1][r++] = v.y;
b.mat[1][r++] = v.z;
b.mat[1][r++] = v.w;
bucket[n] = b;
}
for(auto it : bucket)
{
r = 0;
std::cout << "0:\t" << it.second.mat[0][0] << "\t" << it.second.mat[0][1] << "\t" << it.second.mat[0][2] << "\t" << it.second.mat[0][3] << "\n";
r = 0;
std::cout << "1:\t" << it.second.mat[1][0] << "\t" << it.second.mat[1][1] << "\t" << it.second.mat[1][2] << "\t" << it.second.mat[1][3] << std::endl;
}
return 0;
}
Right now I am totally lost, especially as my mwe works fine.
I am clueless what goes wrong after leaving the for-loop, so thanks for any thought on that!
Indeed, I could just rewrite that section and hope it would work - as my mwe does. But I would like to find out/ get help on finding out what exactly happens between the "assign" for loop and the "retrieve" for loop. Any ideas on that?
I made it work for me now:
Appartenly assigning the values this way:
for(auto c : alphabet::char_map)
{
c.second.face[0][n++] = c.second.offset.x;
//and so on
}
Did not work properly (for whatever reason..)
Changing this into a for(uint16_t i = 32; i < 128; ++i) worked for me. Also it was just the assigning loop, the auto-iterating ofer the map elsewhere works just fine.
I am writing a program to create a horizontal histogram from an array of type double data. I was able to get the program to display the boundaries of each sub-interval along with the correct number of asterisks. However, the data is not formatted.
Here's the part of the program responsible for the output:
// endpoints == the boundaries of each sub-interval
// frequency == the number of values which occur in a given sub-interval
for (int i = 0; i < count - 1; i++)
{
cout << setprecision(2) << fixed;
cout << endPoints[i] << " to " << endPoints[i + 1] << ": ";
for (int j = frequency[i]; j > 0; j--)
{
cout << "*";
}
cout << " (" << frequency[i] << ")" << endl;
}
Here's what my output looks like:
0.00 to 3.90: *** (3)
3.90 to 7.80: * (1)
7.80 to 11.70: * (1)
11.70 to 15.60: (0)
15.60 to 19.50: ***** (5)
Here's what I would like it to look like:
00.00 to 04.00: *** (3)
04.00 to 08.00: * (1)
08.00 to 12.00: * (1)
12.00 to 16.00: (0)
16.00 to 20.00: ****** (6)
I've looked up C++ syntax and have found things like setw() and setprecision(). I tried to use both to format my histogram but have not been able to make it look like the model. I was hoping someone could tell me if I'm on the right track and, if so, how to implement setw() and/or setprecision() to properly format my histogram.
Assuming that all numbers are in the [0,100) interval, what you want is a chain of manipulators like:
#include <iostream>
#include <iomanip>
int main() {
std::cout
<< std::setfill('0') << std::setw(5)
<< std::setprecision(2) << std::fixed
<< 2.0
<< std::endl;
return 0;
}
Which will output:
02.00
This is for a single value, you can easily adapt it to suit your needs.
You could, for instance, turn this into an operator and use it like:
#include <iostream>
#include <iomanip>
class FixedDouble {
public:
FixedDouble(double v): value(v) {}
const double value;
}
std::ostream & operator<< (std::ostream & stream, const FixedDouble &number) {
stream
<< std::setfill('0') << std::setw(5)
<< std::setprecision(2) << std::fixed
<< number.value
<< std::endl;
return stream;
}
int main() {
//...
for (int i = 0; i < count - 1; i++) {
std::cout
<< FixedDouble(endPoints[i])
<< " to "
<< FixedDouble(endPoints[i + 1])
<< ": ";
}
for (int j = frequency[i]; j > 0; j--) {
std::cout << "*";
}
std::cout << " (" << frequency[i] << ")" << std::endl;
//...
}
I'm trying to get some old C++ code up and running. I've gotten it to compile without error, but it immediately segfaults when I run, without entering main. When I use gdb to find out where things are going wrong, I find the following:
(gdb) run
Starting program: /Users/dreens/Documents/OH/extrabuncher2/ParaOHSB
Reading symbols for shared libraries +++. done
Program received signal EXC_BAD_ACCESS, Could not access memory.
Reason: KERN_INVALID_ADDRESS at address: 0x00007fff5636581c
0x000000010000151e in main (argc=1, argv=0x100000ad0) at ParaMainOHSlowerBuncher.cc:13
13 int main(int argc, char *argv[]){
(gdb) backtrace
#0 0x000000010000151e in main (argc=1, argv=0x100000ad0) at ParaMainOHSlowerBuncher.cc:13
(gdb)
Does anyone know what could cause a memory access issue right at the start of the main method?
The code is rather large, but here is the file containing the main method. Could the included .hh and .cc files be a part of the problem? Should I attach them?
Thanks!
David
#include <iostream>
#include <stdlib.h>
#include <math.h>
#include <time.h>
#include "MoleculeEnsemble.hh"
#include "SlowerForceLoadOH32.cc"
#include "SlowerForceLoadOH12.cc"
//#include "SlowerForceLoad3mmBuncher.cc"
#include "SlowerForceLoad4mmBuncher.cc"
using namespace std;
int main(int argc, char *argv[]){
//int main(){
cout << "Ahhhh!" << endl;
/******Parallel Crap********/
/*
int totalnodes = 0;
int mynode = 0;
MPI_Status status;
MPI_Init(&argv,&argc);
MPI_Comm_size(MPI_COMM_WORLD,&totalnodes);
MPI_Comm_rank(MPI_COMM_WORLD,&mynode);
srand(time(NULL)*mynode);
*/
/******Distribution Parameters *******/
long MoleculeNumber = long(5e4);
double Xcenter = 0;
double Ycenter = 0;
double Zcenter = 0;
double DeltaX = 0.0015;
double DeltaY = 0.0015;
double DeltaZ = 0.01;
int FlatX = 1;
int FlatY = 1;
int FlatZ = 1;
double vXcenter = 0;
double vYcenter = 0;
double vZcenter = 406;
double Vcalc = 406;
double vZfinal = 0;
double DeltavX = 2;
double DeltavY = DeltavX;
double DeltavZ = 40;
int FlatvX = 0;
int FlatvY = 0;
int FlatvZ = 0;
int TimeArrayOnly = 0; //Outputs only Time Array
double TimeOffset = 0; //Adds valve-skimmer flight time to ToF array
/*******Overtone Parameters********/
int S = 1; //parameter S=Vz/Vswitch as defined by VDM et al.
int JILAOT = 0; //JILAOT is either 0 or 1, denoting whether or not to use special switching
/*******Hexapole Parameters********/
double VSD = 0.06;
double Voltage = 2000;
double HexRadius = .00268;
double HexStart = .0238;
double HexEnd = .083170;//0.089103;
double HexOn = 1e-6;
double HexOff = 203e-6;//224e-6; 212 for current data; Good = 243e-6 for 408m/s
double DeltaT = 1e-6;
double DeltaTSeqGen = 1e-9; //Need to use smaller time steps for finding the time sequence
double DetectionTime = HexOff; //Use to fake out hex code
double TriggerLatency = 0;//170e-9;
/*******Detection Parameters*******/
double DetectionPosition = double(0.9319);//0.257480; <- for viewing at 31.5 ||||| 0.9428; <-Mag trap(4stages), .9319 <-MagTrap(3Stages)
double IrisWidth = 0.008;//31.5 0.0023 //PostSlower.015;
double LaserRadius = .001;
/*****Bunching Paramaters******/
int BunchNumber = 0;
int NumberUsed = 0;
/*****Timing Variables*********/
time_t start, finish;
time( &start);
/*****Molecule Parameters******/
double mass =double(17*1.672e-27);
/******ToF Detection Arrays and Slowing Parameters *********/
double Phi = double(34.2);
double PhiEB = double(0);
int NumberOfStages = int(142/S); //Use 142 for Big machine
int EBStages = 3; //Larger Add-on stages at end of slower
double BuncherScale = 1;
double Time[int(1e7)];
int ToFSignal32[int(1e7)];
int ToFSignal12[int(1e7)];
double TimeArray[800];
double VExit[800];
double Average32[7];
double Average12[7];
int LOST[200];
/*************Finished ToF Detection Arrays and Slowing Parameters ********/
/******Force Arrays********/
int Xnumber = 111;
int Ynumber = 21;
int Znumber = 21;
int FLength = Xnumber*Ynumber*Znumber;
double AXxDT[FLength];
double AYxDT[FLength];
double AZxDT[FLength];
double AZxDTSeqGen[FLength];
SlowerForceLoadOH32(AZxDT, AYxDT, AXxDT); //Note how Z and X are placed in this function. My matlab code calls the longitudnal dimension X, here it is Z
double DTovermass = DeltaT/mass;
for(int j = 0; j <FLength; j++){
AXxDT[j] = DTovermass*AXxDT[j];
AYxDT[j] = DTovermass*AYxDT[j];
AZxDT[j] = DTovermass*AZxDT[j];
AZxDTSeqGen[j] = DeltaTSeqGen*AZxDT[j]/DeltaT;
}
double AXxDT12[FLength];
double AYxDT12[FLength];
double AZxDT12[FLength];
SlowerForceLoadOH12(AZxDT12, AYxDT12, AXxDT12); //Note how Z and X are placed in this function. My matlab code calls the longitudnal dimension X, here it is Z
for(int j = 0; j <FLength; j++){
AXxDT12[j] = DTovermass*AXxDT12[j];
AYxDT12[j] = DTovermass*AYxDT12[j];
AZxDT12[j] = DTovermass*AZxDT12[j];
}
/********Load Extra Buncher Forces*********/
int XnumberEB = 251;
int YnumberEB = 41;
int ZnumberEB = 41;
int FLengthEB = XnumberEB*YnumberEB*ZnumberEB;
double AXxDTEB[FLengthEB], AYxDTEB[FLengthEB], AZxDTEB[FLengthEB], AZxDTSeqGenEB[FLengthEB];
SlowerForceLoad4mmBuncher(AZxDTEB, AYxDTEB, AXxDTEB);
for(int j = 0; j <FLengthEB; j++)
{
AXxDTEB[j] = DTovermass*AXxDTEB[j]/BuncherScale;
AYxDTEB[j] = DTovermass*AYxDTEB[j]/BuncherScale;
AZxDTEB[j] = DTovermass*AZxDTEB[j]/BuncherScale;
AZxDTSeqGenEB[j] = DeltaTSeqGen*AZxDTEB[j]/(DeltaT*BuncherScale);
}
/********* End All initiliazation ***************************/
/************Beginning Calculation *************************/
//Create Molecule Ensemble
MoleculeEnsemble Alice(MoleculeNumber,Xcenter,Ycenter,Zcenter,DeltaX,DeltaY,DeltaZ,FlatX,FlatY,FlatZ,vXcenter,vYcenter,vZcenter,DeltavX,DeltavY,DeltavZ,FlatvX,FlatvY,FlatvZ);
//MoleculeEnsemble Bob(MoleculeNumber,Xcenter,Ycenter,Zcenter,DeltaX,DeltaY,DeltaZ,FlatX,FlatY,FlatZ,vXcenter,vYcenter,vZcenter,DeltavX,DeltavY,DeltavZ,FlatvX,FlatvY,FlatvZ);
//Generate the Timing Sequence
Alice.TimeArrayGeneratorWithBuncher(Vcalc,Phi,PhiEB,TimeArray,VExit,AZxDTSeqGen,AZxDTSeqGenEB,HexOff,DeltaTSeqGen,BunchNumber,vZfinal,NumberUsed,NumberOfStages,S,EBStages);
/*if(mynode == 0){
cout << "Slowing utilized " << NumberUsed << " stages, yielding a final velocity of " << VExit[NumberUsed] << " m/s." << endl;
cout << endl;
for(int kk = 0; kk < NumberOfStages; kk++){cout << kk << " , " << TimeArray[kk] << " , " << VExit[kk] << endl;}
}*/
/*Alice.MoleculeEnsemble_Averager(Average32);
Bob.MoleculeEnsemble_Averager(Average12);
cout << "Processor: " << mynode << "\t" << sqrt(pow(Average32[3],2)+pow(Average32[4],2)) << ", " << sqrt(pow(Average12[3],2)+pow(Average12[4],2));
cout << " Mean = " << Average32[6] << ", " << Average12[6] << endl << endl << endl;
*/
if(TimeArrayOnly!=1)
{
//Fly the Ensemble through the hexapole
Alice.HexapoleFlightOH(Voltage, HexRadius, HexStart, HexEnd, HexOn, HexOff, DeltaT, double(3/2), DetectionTime);
//Bob.HexapoleFlightOH(Voltage, HexRadius, HexStart, HexEnd, HexOn, HexOff, DeltaT, double(1/2), DetectionTime);
/*
Alice.MoleculeEnsemble_Averager(Average32);
Bob.MoleculeEnsemble_Averager(Average12);
cout << "Processor: " << mynode << "\t" << sqrt(pow(Average32[3],2)+pow(Average32[4],2)) << ", " << sqrt(pow(Average12[3],2)+pow(Average12[4],2));
cout << " Mean = " << Average32[6] << ", " << Average12[6] << endl << endl << endl;
*/
//Fly the Ensemble through the slower
Alice.SlowerFlight(LOST, Time, ToFSignal32, Phi, TimeArray, DeltaT, AXxDT, AYxDT, AZxDT, AXxDTEB, AYxDTEB, AZxDTEB, Xnumber, Ynumber, Znumber, DetectionPosition, IrisWidth, LaserRadius, NumberOfStages, EBStages,S, TriggerLatency);
//Bob.SlowerFlight(LOST, Time, ToFSignal12, Phi, TimeArray, DeltaT, AXxDT12, AYxDT12, AZxDT12, Xnumber, Ynumber, Znumber, DetectionPosition, IrisWidth, LaserRadius, NumberOfStages, EBStages, S, TriggerLatency);
}
/**********Ending Calculation **********************/
//Alice.MoleculeEnsemble_Drawer();
/*
Alice.MoleculeEnsemble_Averager(Average32);
Bob.MoleculeEnsemble_Averager(Average12);
cout << "Processor: " << mynode << "\t" << sqrt(pow(Average32[3],2)+pow(Average32[4],2)) << ", " << sqrt(pow(Average12[3],2)+pow(Average12[4],2));
cout << " Mean = " << Average32[6] << ", " << Average12[6] << endl << endl;
*/
//Output ToF signal
if(TimeArrayOnly!=1)
{
for(int ii = 0; ii < int(1e7); ii++)
{
if(ToFSignal32[ii] > 0 && Time[ii] > 3e-3)
{
cout << Time[ii]+TimeOffset << "," << ToFSignal32[ii] << endl;
//+double(VSD/vZcenter)+38e-6 << "," << ToFSignal32[ii] << endl;
}
if(ToFSignal12[ii] > 0 && Time[ii] > 3e-3)
{
cout << Time[ii]+TimeOffset << "," << ToFSignal12[ii] << endl;
//+double(VSD/vZcenter)+38e-6 << "," << ToFSignal12[ii] << endl;
}
}
}
if(TimeArrayOnly==1)
{
for(int ii = 0; ii < NumberOfStages+EBStages+1; ii++)
{
cout << ii << "\t" << TimeArray[ii] << "\t" << VExit[ii] << endl;
//+double(VSD/vZcenter)+double(265e-6) << "\t" << VExit[ii] << endl;
}
}
/*for(int ii = 0; ii < NumberOfStages; ii++)
{
cout << ii << "\t" << LOST[ii] << endl;
}
*/
/*
MPI_Finalize();
*/
}
You're out of stack space.
You declare very large arrays in your code (over 10 million elements), which are all allocated on the stack. Instead of declaring the arrays statically, use dynamic memory allocation. So, instead of
double Time[int(1e7)];
write
double* Time;
Time = new double[int(1e7)];
and hope to have enough RAM in your computer :)
I have writtent a small C++ console application with code::blocks that loads
an array of values from a CSV file, performs a special "inverted" random dithering on the values, and exports the result as a PBM file (a bitmap).
The density of black pixels on the final PBM picture depends on 3 independent variables: "Reflectance of the white", "Reflectance of the black", and the values of the CSV.
The reason I use a CSV file is because I don't know how I can directly load a TIFF file into my script. The values of my file "wall.csv" are produced by a python script that transforms any tiff file in a csv...
Could you please check my code and advise for a solution to load a TIFF and detect automatically the size of the image in pixels?
The variables colo and lines define the size of the image contained as ASCII data in the CSV...
And the image values are loaded in the vector <float> CSV
What library would you use to load the tiff?
Thanks!
code:
#include <deque>
#include <cmath>
#include <iostream>
#include <fstream>
#include <algorithm>
#include <random>
#include <cstdlib>
using namespace std;
deque <float> CSV; // CSV input values, "PHOTOMETRY"
deque <float> RND; // will contain random values from 0.0 to 1.0
int colo = 0; // variables inputed
int lines = 0; // lines
float YBK = 0; // Reflectance White
float YW = 0; // Reflectance Black
float Lmax = 0; // variables to be computed
float Lmin = 10000000; // arbitrarily high value
float NBK = 0; // will contain a normalized Black value
float NW = 1; // normalized white value
float CRATIO = 0; // Black to White dynamic ratio
float LRATIO = 0; // Lowest to Highest pixel value dynamic ratio
float Z = 0; // processing variables
float X = 0;
float aBK = 0; // computed density of black at each pixel
float vRND = 0; // random value container
float IO = 0;
int main(){
cout << "please put a file named wall.csv" << endl << "in the same forler as this executable" << endl << endl;
cout << "how many:" << endl << "columns does the CSV has?" << endl;
cin >> colo;
cout << "lines does the CSV has?" << endl;
cin >> lines;
cout << "reflectance of the WHITE (CIE Y)?" << endl;
cin >> YW;
cout << "reflectance of the BLACK (CIE Y)?" << endl;
cin >> YBK;
NBK = YBK / YW; // normalized BK
CRATIO = NW / NBK; // correction Ratio
int C = lines * colo; // cells
cout << endl << " there are: " << colo << " columns";
cout << endl << " and : " << lines << " lines " ;
cout << endl << " that makes " << C << " cells " << endl;
cout << endl << " correction ratio is: " << CRATIO << endl << endl;
///_____ IMPORT THE PHOTOMETRIC DATA
cout << "...importing the photometric data" << endl;
float x = 0; // a variable that will contain a value from the file
ifstream ifs ("wall.csv");
char dummy;
for (int i = 0; i < lines; ++i){
for (int i = 0; i < colo; ++i){
ifs >> x;
if (x > Lmax) {
Lmax = x; // determines the highest pixel value
}
if (x < Lmin) {
Lmin = x; // determines the lowest pixel value
}
CSV.push_back(x);
// So the dummy won't eat digits
if (i < (colo - 1))
ifs >> dummy;
}}
ifstream ifs_close();
LRATIO = Lmax / Lmin;
cout << "...photometric data imported" << endl;
cout << endl << " maximum Luminance is: " << Lmax;
cout << endl << " minimum Luminance is: " << Lmin << endl;
cout << endl << "...luminance ratio is: " << LRATIO;
if (LRATIO > CRATIO) {
cout << endl << "...luminance ratio is: " << LRATIO;
cout << endl << "...this is too high, ending..." << '\a';
return(0);
}
cout << endl << "...luminance can be corrected :)" << endl;
///______ CREATE RANDOM VALUES BETWEEN 0 & 1
std::default_random_engine generator;
std::uniform_real_distribution <double> distribution(0.0,1.0);
for (int i=0; i<C; ++i) {
double number = distribution(generator);
RND.push_back(number);
}
cout << endl << "...random values created" << endl;
///_______ process & export to PBM
ofstream output_file("./wall.pbm");
output_file << "P1" << "\n" << colo << " " << lines << "\n"; /// PBM HEADER
cout << endl << "...file header written" << endl;
cout << endl << "...computing";
int CELLS = C; // copy the amount of cells
int LINEW = colo;
int PERCENT = 100;
while (CELLS > 0) {
while (LINEW > 0) {
Z = Lmin/CSV.front(); /// processing calculus
X = (NBK - Z)/(NBK - NW);
aBK = (1 - X);
vRND = RND.front();
if (aBK > (vRND)) {
IO = 1;
}
else {
IO = 0;
}
LINEW = LINEW - 1;
CELLS = CELLS - 1;
PERCENT = PERCENT - CELLS / C;
output_file << IO << "\n";
//cout << ERR << " "; /// fancy...
CSV.erase(CSV.begin());
RND.erase(RND.begin());
}
LINEW = colo;
}
cout << endl << "...computing done" << endl;
cout << "...file written";
output_file.close();
return(0);
}
Check out lib tiff. OpenCV just uses lib tiff as well.
http://www.libtiff.org/
I have never used CGAL and have got almost no C/C++ experience. But following
Google I have however managed to compile the example "Alpha_shapes_3"
(\CGAL-4.1-beta1\examples\Alpha_shapes_3) on a Windows 7 64bit machine using
visual studio 2010.
Now if we check the source code for the program "ex_alpha_shapes_3" we
notice that a data file called "bunny_1000" is red where the 3d point
cluster resides.
Now my question is how can I change the source code so that after the alpha
shape is computed for the given points, surface mesh of the alpha shape is
saved/wrote in an external file. It can be simply the list of polygons and
their respective 3D vertices. I guess these polygons will be defining the
surface mesh of the alpha shape. If I can do that I can see the output of
the alpha shape generation program in an external tool I am familiar with.
I know this is very straightforward but I could not figure this out with my
limited knowledge of CGAL.
I know you gueys have the code but I am pasting it again for completion.
#include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
#include <CGAL/Delaunay_triangulation_3.h>
#include <CGAL/Alpha_shape_3.h>
#include <fstream>
#include <list>
#include <cassert>
typedef CGAL::Exact_predicates_inexact_constructions_kernel Gt;
typedef CGAL::Alpha_shape_vertex_base_3<Gt> Vb;
typedef CGAL::Alpha_shape_cell_base_3<Gt> Fb;
typedef CGAL::Triangulation_data_structure_3<Vb,Fb> Tds;
typedef CGAL::Delaunay_triangulation_3<Gt,Tds> Triangulation_3;
typedef CGAL::Alpha_shape_3<Triangulation_3> Alpha_shape_3;
typedef Gt::Point_3 Point;
typedef Alpha_shape_3::Alpha_iterator Alpha_iterator;
int main()
{
std::list<Point> lp;
//read input
std::ifstream is("./data/bunny_1000");
int n;
is >> n;
std::cout << "Reading " << n << " points " << std::endl;
Point p;
for( ; n>0 ; n--) {
is >> p;
lp.push_back(p);
}
// compute alpha shape
Alpha_shape_3 as(lp.begin(),lp.end());
std::cout << "Alpha shape computed in REGULARIZED mode by default"
<< std::endl;
// find optimal alpha value
Alpha_iterator opt = as.find_optimal_alpha(1);
std::cout << "Optimal alpha value to get one connected component is "
<< *opt << std::endl;
as.set_alpha(*opt);
assert(as.number_of_solid_components() == 1);
return 0;
}
After searching a lot in the internet I found that probably we need to use something like
std::list<Facet> facets;
alpha_shape.get_alpha_shape_facets
(
std::back_inserter(facets),Alpha_shape::REGULAR
);
But I am still completely clueless how to use this in the above code!
As documented here, a facet is a pair (Cell_handle c,int i) defined as the facet in c opposite to the vertex of index i.
On this page, you have the description of how the vertex indices of a cell are.
In the following code sample, I added a small output that prints an OFF file on cout by duplicating the vertices. To do something clean, you can either use a std::map<Alpha_shape_3::Vertex_handle,int> to associate a unique index per vertex or add an info to the vertices like in those examples.
/// collect all regular facets
std::vector<Alpha_shape_3::Facet> facets;
as.get_alpha_shape_facets(std::back_inserter(facets), Alpha_shape_3::REGULAR);
std::stringstream pts;
std::stringstream ind;
std::size_t nbf=facets.size();
for (std::size_t i=0;i<nbf;++i)
{
//To have a consistent orientation of the facet, always consider an exterior cell
if ( as.classify( facets[i].first )!=Alpha_shape_3::EXTERIOR )
facets[i]=as.mirror_facet( facets[i] );
CGAL_assertion( as.classify( facets[i].first )==Alpha_shape_3::EXTERIOR );
int indices[3]={
(facets[i].second+1)%4,
(facets[i].second+2)%4,
(facets[i].second+3)%4,
};
/// according to the encoding of vertex indices, this is needed to get
/// a consistent orienation
if ( facets[i].second%2==0 ) std::swap(indices[0], indices[1]);
pts <<
facets[i].first->vertex(indices[0])->point() << "\n" <<
facets[i].first->vertex(indices[1])->point() << "\n" <<
facets[i].first->vertex(indices[2])->point() << "\n";
ind << "3 " << 3*i << " " << 3*i+1 << " " << 3*i+2 << "\n";
}
std::cout << "OFF "<< 3*nbf << " " << nbf << " 0\n";
std::cout << pts.str();
std::cout << ind.str();
Here is my code, which outputs vtk file for visualization in Paraview. Comparing with slorior's solutions, no duplicated points are saved in the file. But my code is just for the visualization, if you need to figure out the exterior or interior simplexes, you should modify the code to get these results.
void writevtk(Alpha_shape_3 &as, const std::string &asfile) {
// http://cgal-discuss.949826.n4.nabble.com/Help-with-filtration-and-filtration-with-alpha-values-td4659524.html#a4659549
std::cout << "Information of the Alpha_Complex:\n";
std::vector<Alpha_shape_3::Cell_handle> cells;
std::vector<Alpha_shape_3::Facet> facets;
std::vector<Alpha_shape_3::Edge> edges;
// tetrahedron = cell, they should be the interior, it is inside the 3D space
as.get_alpha_shape_cells(std::back_inserter(cells), Alpha_shape_3::INTERIOR);
// triangles
// for the visualiization, don't need regular because tetrahedron will show it
//as.get_alpha_shape_facets(std::back_inserter(facets), Alpha_shape_3::REGULAR);
as.get_alpha_shape_facets(std::back_inserter(facets), Alpha_shape_3::SINGULAR);
// edges
as.get_alpha_shape_edges(std::back_inserter(edges), Alpha_shape_3::SINGULAR);
std::cout << "The alpha-complex has : " << std::endl;
std::cout << cells.size() << " cells as tetrahedrons" << std::endl;
std::cout << facets.size() << " triangles" << std::endl;
std::cout << edges.size() << " edges" << std::endl;
size_t tetra_num, tri_num, edge_num;
tetra_num = cells.size();
tri_num = facets.size();
edge_num = edges.size();
// vertices: points <-> id
std::map<Point, size_t> points;
size_t index = 0;
// finite_.. is from DT class
for (auto v_it = as.finite_vertices_begin(); v_it != as.finite_vertices_end(); v_it++) {
points[v_it->point()] = index;
index++;
}
// write
std::ofstream of(asfile);
of << "# vtk DataFile Version 2.0\n\nASCII\nDATASET UNSTRUCTURED_GRID\n\n";
of << "POINTS " << index << " float\n";
for (auto v_it = as.finite_vertices_begin(); v_it != as.finite_vertices_end(); v_it++) {
of << v_it->point() << std::endl;
}
of << std::endl;
of << "CELLS " << tetra_num + tri_num + edge_num << " " << 5 * tetra_num + 4 * tri_num + 3 * edge_num << std::endl;
for (auto cell:cells) {
size_t v0 = points.find(cell->vertex(0)->point())->second;
size_t v1 = points.find(cell->vertex(1)->point())->second;
size_t v2 = points.find(cell->vertex(2)->point())->second;
size_t v3 = points.find(cell->vertex(3)->point())->second;
of << "4 " << v0 << " " << v1 << " " << v2 << " " << v3 << std::endl;
}
// https://doc.cgal.org/latest/TDS_3/classTriangulationDataStructure__3.html#ad6a20b45e66dfb690bfcdb8438e9fcae
for (auto tri_it = facets.begin(); tri_it != facets.end(); ++tri_it) {
of << "3 ";
auto tmp_tetra = tri_it->first;
for (int i = 0; i < 4; i++) {
if (i != tri_it->second) {
of << points.find(tmp_tetra->vertex(i)->point())->second << " ";
}
}
of << std::endl;
}
// https://doc.cgal.org/latest/TDS_3/classTriangulationDataStructure__3.html#af31db7673a6d7d28c0bb90a3115ac695
for (auto e : edges) {
of << "2 ";
auto tmp_tetra = e.get<0>();
int p1, p2;
p1 = e.get<1>();
p2 = e.get<2>();
of << points.find(tmp_tetra->vertex(p1)->point())->second << " "
<< points.find(tmp_tetra->vertex(p2)->point())->second << std::endl;
}
of << std::endl;
of << "CELL_TYPES " << tetra_num + tri_num + edge_num << std::endl;
for (int i = 0; i < tetra_num; i++) {
of << "10 ";
}
for (int i = 0; i < tri_num; i++) {
of << "5 ";
}
for (int i = 0; i < edge_num; i++) {
of << "3 ";
}
of << std::endl;
of.close();
}