Split up files. Added rapidxml for xml parsing.

Makefile

@@ -1,2 +1,4 @@
-a.out: main.cpp
+a.out: *.cpp
-	clang++ -std=c++17 -g -o a.out main.cpp -lGL -lGLU -lglut -lstdc++fs
+	clang++ -std=c++17 -g -o a.out main.cpp \
+camera/Camera.cpp Track.cpp Xml.cpp \
+-lGL -lGLU -lglut -lstdc++fs

Track.cpp

@@ -0,0 +1,152 @@
+#include "Track.h"
+#include "Xml.h"
+
+#include <GL/glut.h>
+
+#include <syslog.h>
+#include <iostream>
+#include <iomanip>
+#include <fstream>
+
+bool ParseFile(std::vector<Track> &out_tracks,
+               const std::string &file_and_path)
+{
+	std::ifstream ifs(file_and_path);
+	if(!ifs.is_open())
+	{
+		std::cerr << "Couldn't open " << file_and_path << "." << std::endl;
+		return false;
+	}
+
+	// get size
+	ifs.seekg(0, std::ios_base::end);
+	auto end = ifs.tellg();
+	std::string file_str(end, '\0');
+	ifs.seekg(0, std::ios_base::beg); // back to beginning to read
+	ifs.read(&file_str[0], end);
+
+	// parse it (warning: possibly destructive / not const)
+	using namespace rapidxml;
+	xml_document<> doc;    // character type defaults to char
+	doc.parse<0>(&file_str[0]);    // 0 means default parse flags
+
+	xml_node<> *node = recursive_find_next_node(doc.first_node(), "trkpt");
+	if(!node)
+	{
+		std::cerr << "Couldn't find a <trkpt> node for file \"" << file_and_path << "\"." << std::endl;
+		return false;
+	}
+
+	Track t;
+
+	// recursively search for all trkpt nodes:
+	for(; node; node = recursive_find_next_node(node->next_sibling(), "trkpt"))
+	{
+		bool found_lat = false;
+		bool found_lon = false;
+		bool found_ele = false;
+
+		Point p;
+		for(xml_attribute<> *attr = node->first_attribute();
+		    attr;
+		    attr = attr->next_attribute())
+		{
+			if(std::string(attr->name()) == "lat")
+			{
+				try {
+					p.lat = std::atof(attr->value());
+					found_lat = true;
+				} catch(const std::exception &e) {
+					syslog(LOG_USER|LOG_DEBUG,"%s:%d:%s Error Parsing lat",
+					       __FILE__,__LINE__,__PRETTY_FUNCTION__);
+				}
+			}
+			if(std::string(attr->name()) == "lon")
+			{
+				try {
+					p.lon = std::atof(attr->value());
+					found_lon = true;
+				} catch(const std::exception &e) {
+					syslog(LOG_USER|LOG_DEBUG,"%s:%d:%s Error Parsing lon",
+					       __FILE__,__LINE__,__PRETTY_FUNCTION__);
+				}
+			}
+		}
+		auto ele_node = node->first_node("ele");
+		if(ele_node)
+		{
+			try {
+				p.ele = std::atof(ele_node->value());
+				found_ele = true;
+			} catch(const std::exception &e) {
+				syslog(LOG_USER|LOG_DEBUG,"%s:%d:%s Error Parsing ele",
+				       __FILE__,__LINE__,__PRETTY_FUNCTION__);
+			}
+		}
+
+		if(found_lat && found_lon && found_ele)
+			t.points.push_back(p);
+		else if(found_lat || found_lon || found_ele)
+			syslog(LOG_USER|LOG_DEBUG, "%s:%d:%s Incomplete trkpt",
+			       __FILE__,__LINE__,__PRETTY_FUNCTION__);
+	}
+
+	// Bring track to a scale that we're comfortable rendering:
+	// Grab stats:
+	bool first = true;
+	for(auto &p : t.points)
+	{
+		if(first)
+		{
+			first = false;
+			t.min.lat = t.max.lat = p.lat;
+			t.min.lon = t.max.lon = p.lon;
+			t.min.ele = t.max.ele = p.ele;
+		}
+		else
+		{
+			if(p.lat < t.min.lat)
+				t.min.lat = p.lat;
+			else if(p.lat > t.max.lat)
+				t.max.lat = p.lat;
+			if(p.lon < t.min.lon)
+				t.min.lon = p.lon;
+			else if(p.lon > t.max.lon)
+				t.max.lon = p.lon;
+			if(p.ele < t.min.ele)
+				t.min.ele = p.ele;
+			else if(p.ele > t.max.ele)
+				t.max.ele = p.ele;
+		}
+		p.lat *= 500;
+		p.lon *= 500;
+		p.ele *= 0.2;
+	}
+
+	out_tracks.push_back(t);
+	ifs.close();
+
+	std::cout << std::setw(6) << t.points.size() << " tracks points "
+	          << "found in \"" << file_and_path << "\"." << std::endl;
+
+	return true;
+}
+
+void draw(const Track &track)
+{
+	// glLineWidth(1.0f);
+
+	// Draw bike path
+	glBegin(GL_LINE_STRIP);
+	for(auto p : track.points)
+	{
+		auto val = (50 + (p.ele * 10)) / 180.0;
+		glColor3d(val / 2.0, val / 2.0, val / 2.0);
+		glVertex3f(p.lat, p.ele, p.lon);
+	}
+	glEnd();
+
+	// usleep(100000);
+
+	glutPostRedisplay();
+}

Track.h

@@ -0,0 +1,27 @@
+#ifndef TRACK_H
+#define TRACK_H
+
+#include <vector>
+#include <string>
+
+struct Point {
+	float lat;
+	float lon;
+	float ele;
+};
+
+struct Track {
+public:
+	std::vector<Point> points;
+	Point min;
+	Point max;
+};
+
+static std::vector<Track> tracks;
+
+bool ParseFile(std::vector<Track> &out_tracks,
+               const std::string &file_and_path);
+
+void draw(const Track &track);
+
+#endif

Xml.cpp

@@ -0,0 +1,26 @@
+#include "Xml.h"
+
+using namespace rapidxml;
+
+xml_node<>* recursive_find_next_node(xml_node<> *node, const std::string &node_name)
+{
+	if(!node)
+		return nullptr;
+
+	// go through each sibling node...
+	for(; node; node = node->next_sibling())
+	{
+		if(node->name() == node_name)
+			return node;
+
+		// first make sure none of the children nodes have this name, too.
+		if(node->first_node() != nullptr)
+		{
+			auto child_node = recursive_find_next_node(node->first_node(), node_name);
+			if(child_node)
+				return child_node;
+		}
+	}
+
+	return nullptr;
+}

Xml.h

@@ -0,0 +1,13 @@
+#ifndef XML_H
+#define XML_H
+
+#include "rapidxml.hpp"
+
+#include <string>
+
+rapidxml::xml_node<>* recursive_find_next_node(
+	rapidxml::xml_node<> *node,
+	const std::string &node_name
+	);
+
+#endif

main.cpp

@@ -1,11 +1,13 @@
-#include "rapidxml.hpp"
+#include "camera/Camera.h"
+#include "Xml.h"
+#include "Track.h"
 
 #include <GL/glut.h>
 
 #include <experimental/filesystem>
 
+#include <syslog.h>
 #include <cstdlib>
-#include <fstream>
 #include <iostream>
 #include <math.h> // fmod
 #include <unistd.h>
@@ -14,119 +16,41 @@
 GLfloat light_diffuse[] = {1.0, 0.0, 0.0, 1.0};  /* Red diffuse light. */
 GLfloat light_position[] = {1.0, 1.0, 1.0, 0.0};  /* Infinite light location. */
 
-struct Point {
+Camera camera;
-	float lat;
-	float lon;
-	float ele;
-};
-
-static std::vector<std::vector<Point> > tracks;
-
-bool ParseFile(std::vector<std::vector<Point>> &out_tracks,
-               const std::string &file_and_path)
-{
-	std::ifstream ifs(file_and_path);
-	if(!ifs.is_open())
-	{
-		std::cerr << "Couldn't open " << file_and_path << "." << std::endl;
-		return -2;
-	}
-
-	std::string line = "";
-	bool first = true;
-	float diff_lat, diff_lon, diff_ele;
-	std::vector<Point> track;
-	while(std::getline(ifs, line))
-	{
-		// get starting position of field NAME
-		auto lat = line.find("lat=\"");
-		if(lat == std::string::npos)
-			continue;
-		// get ending position of field DATA
-		auto lat_to = line.find("\"", lat);
-		if(lat_to == std::string::npos)
-			continue;
-
-		// get starting position of field NAME
-		auto lon = line.find("lon=\"", lat_to);
-		if(lon == std::string::npos)
-			continue;
-		// get ending position of field DATA
-		auto lon_to = line.find("\"", lon);
-		if(lon_to == std::string::npos)
-			continue;
-
-		auto ele = line.find("<ele>", lon_to);
-		if(ele == std::string::npos)
-			continue;
-		auto ele_to = line.find("</ele>", ele);
-		if(ele_to == std::string::npos)
-			continue;
-
-		Point p;
-		try {
-			p.lat = std::atof(line.substr(lat + 5, lat_to).c_str()) * 200;
-			p.lon = std::atof(line.substr(lon + 5, lon_to).c_str()) * 200;
-			p.ele = std::atof(line.substr(ele + 5, ele_to).c_str()) * 0.1;
-		} catch (const std::exception &e) {
-			std::cerr << "Error in file " << file_and_path
-			          << ", line \"" << line << "\"."
-			          << std::endl;
-			continue;
-		}
-
-		track.push_back(p);
-	}
-	out_tracks.push_back(track);
-	ifs.close();
-}
 
 // TODO(dev):
 //  As per https://www.opengl.org/resources/libraries/glut/spec3/node11.html
 //  "Therefore, GLUT programs should not assume the window was created at the specified size or position.
 //   A GLUT program should use the window's reshape callback to determine the true size of the window."
 
-void draw(const std::vector<Point> &points)
-{
-	// glLineWidth(1.0f);
-
-	// Draw bike path
-	glBegin(GL_LINE_STRIP);
-	for(auto p : points)
-	{
-		auto val = (50 + (p.ele * 10)) / 180.0;
-		glColor3d(val, val, val);
-		glVertex3f(p.lat, p.ele, p.lon);
-	}
-	glEnd();
-
-	// usleep(100000);
-
-	glutPostRedisplay();
-}
-
 void draw_origin()
 {
-	glBegin(GL_LINES);
-
 	// X:
+	glBegin(GL_LINE_STRIP);
+	glColor3d(0, 0, 0);
+	glVertex3f(-10.0f, 0.0f, 0.0f);
 	glColor3d(255, 0, 0);
-	glVertex3f(-1.0f, 0.0f, 0.0f);
+	glVertex3f(0.0f, 0.0f, 0.0f);
 	glColor3d(0, 0, 0);
 	glVertex3f(10.0f, 0.0f, 0.0f);
+	glEnd();
 
 	// Y:
+	glBegin(GL_LINE_STRIP);
+	glVertex3f(0.0f, -10.0f, 0.0f);
 	glColor3d(0, 255, 0);
-	glVertex3f(0.0f, -1.0f, 0.0f);
+	glVertex3f(0.0f, 0.0f, 0.0f);
 	glColor3d(0, 0, 0);
 	glVertex3f(0.0f, 10.0f, 0.0f);
+	glEnd();
 
 	// Z:
-	glColor3d(0, 0, 255);
+	glBegin(GL_LINE_STRIP);
 	glVertex3f(0.0f, 0.0f, -10.0f);
+	glColor3d(0, 0, 255);
+	glVertex3f(0.0f, 0.0f, 0.0f);
 	glColor3d(0, 0, 0);
 	glVertex3f(0.0f, 0.0f, 10.0f);
-
 	glEnd();
 }
 
@@ -136,12 +60,16 @@ void display()
 	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 	glLoadIdentity();
 
+	glLineWidth(1.0f);
+
+	//camera.RotateYaw(0.01);
+
 	static double asdf = -10.0;
 	asdf += 0.02;
 	if(asdf > 15.0)
 		asdf = -15.0;
-	gluLookAt(-15, 12.0, -asdf,  /* eye is at */
+	gluLookAt(-15.0, 30.0, -asdf,  /* eye is at */
-	          0.0, 6.0, 0.0,  /* center is at */
+	          0.0, 5.0, 0.0,  /* center is at */
 	          0.0, 1.0, 0.0);    /* up is in positive Y direction */
 
 	draw_origin();
@@ -197,18 +125,55 @@ int main(int argc, char *argv[])
 	}
 
 	for(auto file : files)
-	{
+		ParseFile(tracks, file);
-		// NOTE(dev): OLD:
-		if(!ParseFile(tracks, file))
-			return -3; // couldn't parse file
 
-		// NOTE(dev): NEW:
+	// NORMALIZE TRACKS TO VIEWPORT:
-		// TODO(dev): Xml Parser
+	bool first = true;
+	float min_lat, min_lon, min_ele, max_lat, max_lon, max_ele;
+	for(auto &track : tracks)
+	{
+		for(auto &p : track.points)
+		{
+			if(first)
+			{
+				first = false;
+				min_lat = max_lat = p.lat;
+				min_lon = max_lon = p.lon;
+				min_ele = max_ele = p.ele;
+			}
+			else
+			{
+				if(p.lat < min_lat)
+					min_lat = p.lat;
+				else if(p.lat > max_lat)
+					max_lat = p.lat;
+				if(p.lon < min_lon)
+					min_lon = p.lon;
+				else if(p.lon > max_lon)
+					max_lon = p.lon;
+				if(p.ele < min_ele)
+					min_ele = p.ele;
+				else if(p.ele > max_ele)
+					max_ele = p.ele;
+			}
+		}
+	}
+	auto lat_diff = min_lat + ((max_lat - min_lat) / 2.0);
+	auto lon_diff = min_lon + ((max_lon - min_lon) / 2.0);
+	auto ele_diff = min_ele;
+	for(auto &track : tracks)
+	{
+		for(auto &p : track.points)
+		{
+			p.lat -= lat_diff;
+			p.lon -= lon_diff;
+			p.ele -= ele_diff;
+		}
 	}
 
 	glutInitDisplayMode(GLUT_DOUBLE | GLUT_DEPTH | GLUT_ALPHA | GLUT_MULTISAMPLE);
 	glutInit(&argc, argv);
-	glutCreateWindow("test opengl program");
+	glutCreateWindow("3D GPX Viewer");
 	glutDisplayFunc(display);
 
 	// NOTE(dev): lmfao:
@@ -216,6 +181,9 @@ int main(int argc, char *argv[])
 	glutSetCursor(GLUT_CURSOR_FULL_CROSSHAIR);
 
 	init();
+	camera.Init();
+	camera.Fly(50);
+	camera.RotatePitch(-89 * M_PI / 180.0);
 	glutMainLoop();
 
 	return 0;