Rendering failure when generating bubble charts

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Generating a bubble chart can sometimes result in a display issue.

In very rare cases, execution reaches

vizzu-lib/src/chart/speclayout/bubblechart.cpp

Line 86 in 78ccbd5

// TODO bubblechart generation failed. It need a fix.

The unit tests below do not directly hit this code path, but they help illustrate how execution can reach it.

#include <cmath>
#include <iostream>
#include <sstream>
#include <vector>

#include "../util/test.h"

#include "chart/speclayout/bubblechart.h"

using test::operator""_suite;
using test::check;

const static auto tests =
	"Chart::Bubblechart"_suite
	| "short fail" |
	[]
	{
		std::vector<double> areas;
		areas.insert(areas.end(), 7, 1.0);
		areas.insert(areas.end(), 34, 0.1);
		auto&& bc{Vizzu::Charts::BubbleChart(areas)};
		auto&& nextCirc = bc.markers.at(8).circle();
		auto&& lastCirc = bc.markers.back().circle();

		check->* (nextCirc.center - lastCirc.center).abs() >= nextCirc.radius + lastCirc.radius;

	}

	| "long fail" |
	[]
	{
		std::vector<double> areas;
		areas.insert(areas.end(), 6, 1.0);
		areas.insert(areas.end(), 1, 0.64);
		areas.insert(areas.end(), 124, 0.008);
		auto&& bc{Vizzu::Charts::BubbleChart(areas)};

		auto&& nextCirc = bc.markers.at(12).circle();
		auto&& lastCirc = bc.markers.back().circle();
		check->* (nextCirc.center - lastCirc.center).abs() >= nextCirc.radius + lastCirc.radius;
	};

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An example where we hit that code