Method DoQuantizeModal

Src/Quantize.cpp:122–236

void Viewer::DoQuantizeModal(bool quantizeImagePressed)
{
	if (quantizeImagePressed)
		ImGui::OpenPopup("Quantize");

	float modalWidth = Gutil::GetUIParamScaled(308.0f, 2.5f);
	bool isOpenQuantizeImage = true;
	ImGui::SetNextWindowSize(tVector2(modalWidth, 0.0f));
	if (!ImGui::BeginPopupModal("Quantize", &isOpenQuantizeImage, ImGuiWindowFlags_AlwaysAutoResize | ImGuiWindowFlags_NoScrollbar))
		return;

	float buttonWidth	= Gutil::GetUIParamScaled(76.0f, 2.5f);
	float itemWidth		= Gutil::GetUIParamScaled(160.0f, 2.5f);

	tAssert(CurrImage);
	static int method = int(tImage::tQuantize::Method::Wu);
	static int spatialFilterSize = 1;
	static float spatialDitherLevel = 0.0f;
	static int neuSampleFactor = 1;
	static int numColours = 256;

	DoQuantizeInterface(method, spatialFilterSize, spatialDitherLevel, neuSampleFactor, itemWidth);

	ImGui::SetNextItemWidth(itemWidth);
	ImGui::InputInt("Num Colours", &numColours);
	ImGui::SameLine();
	Gutil::HelpMark
	(
		"The number of colours you are quantizing to. Must be between 2 and 256."
	);
	tMath::tiClamp(numColours, 2, 256);

	static bool checkExact = true;
	ImGui::Checkbox("Check Exact", &checkExact);
	ImGui::SameLine();
	Gutil::HelpMark
	(
		"If Check-Exact is true pressing Quantize will inspect all image pixels in case there are\n"
		"fewer (or equal) colours than the number of colours requested. If this is true then the\n"
		"image is exactly representable already and the quantize is not needed. If false the\n"
		"quantize will proceed either way, and the chosen quantize method may adjust the colours."
	);

	// This is so we can print a warning if it's going to take a really long time.
	float quantizeDurationApprox = ComputeApproxQuantizeDuration(CurrImage, tImage::tQuantize::Method(method), numColours);
	float maxDurationBeforeWarning = 10.0f;
	if (quantizeDurationApprox > maxDurationBeforeWarning)
	{
		ImGui::Text
		(
			"\n"
			"Based on the image resolution, quantization\n"
			"method, and number of colours, this operation\n"
			"will take more than %d seconds.\n\n"
			"Consider a different method or reduce the\n"
			"number of colours.",
			int(quantizeDurationApprox)
		);