Draw markers better next to the position slider (#3005).

3 files changed, 252 insertions, 0 deletions

diff --git a/src/lib/layout_markers.cc b/src/lib/layout_markers.cc
new file mode 100644
index 000000000..7b16b07f1
--- /dev/null
+++ b/src/lib/layout_markers.cc
@@ -0,0 +1,158 @@
+/*
+    Copyright (C) 2025 Carl Hetherington <cth@carlh.net>
+
+    This file is part of DCP-o-matic.
+
+    DCP-o-matic is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    DCP-o-matic is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with DCP-o-matic.  If not, see <http://www.gnu.org/licenses/>.
+
+*/
+
+
+#include "dcpomatic_time.h"
+#include "layout_markers.h"
+#include <dcp/types.h>
+#include <functional>
+#include <iostream>
+#include <map>
+#include <string>
+#include <vector>
+
+#include "i18n.h"
+
+
+using std::function;
+using std::map;
+using std::max;
+using std::min;
+using std::pair;
+using std::string;
+using std::vector;
+using namespace std::placeholders;
+
+
+vector<MarkerLayoutComponent>
+layout_markers(
+	map<dcp::Marker, dcpomatic::DCPTime> const& markers,
+	int width_in_pixels,
+	dcpomatic::DCPTime width_in_time,
+	int label_to_end_gap,
+	int outside_label_gap,
+	function<int (string)> text_width
+)
+{
+	float const pixels_per_unit_time = static_cast<float>(width_in_pixels) / width_in_time.get();
+	auto pixels_between = [&](dcpomatic::DCPTime t1, dcpomatic::DCPTime t2) {
+		return pixels_per_unit_time * t2.get() - pixels_per_unit_time * t1.get();
+	};
+
+	vector<AllocationRow> allocations;
+
+	auto allocate = [&](int x1, int x2) -> int {
+		int index = 0;
+		for (auto& row: allocations) {
+			if (row.allocate(x1, x2)) {
+				return index;
+			}
+			++index;
+		}
+
+		auto row = AllocationRow();
+		row.allocate(x1, x2);
+		allocations.push_back(row);
+		return index;
+	};
+
+	vector<MarkerLayoutComponent> components;
+	auto layout_pair = [&](string name, pair<dcp::Marker, dcpomatic::DCPTime> start, pair<dcp::Marker, dcpomatic::DCPTime> end) {
+		auto const width = text_width(name);
+		int const x1 = floor(pixels_per_unit_time * start.second.get());
+		int const x2 = ceil(pixels_per_unit_time * end.second.get());
+
+		int label_x = 0;
+		int y = 0;
+
+		if (pixels_between(start.second, end.second) <= text_width(name)) {
+			if (x1 > width_in_pixels / 2) {
+				label_x = x1 - outside_label_gap - width;
+				y = allocate(x1 - outside_label_gap - width, x2);
+			} else {
+				label_x = x2 + outside_label_gap;
+				y = allocate(x1, x2 + outside_label_gap + width);
+			}
+		} else {
+			label_x = (x1 + x2 - width) / 2;
+			y = allocate(x1, x2);
+		}
+
+		components.push_back(MarkerLayoutComponent{MarkerLayoutComponent::Type::LEFT, x1, y, start.first, start.second});
+		components.push_back(MarkerLayoutComponent{MarkerLayoutComponent::Type::RIGHT, x2, y, end.first, end.second});
+		components.push_back(MarkerLayoutComponent{MarkerLayoutComponent::Type::LABEL, label_x, width, y, name});
+		components.push_back(MarkerLayoutComponent{MarkerLayoutComponent::Type::LINE, x1, x2, y});
+	};
+
+	auto layout_left = [&](string name, pair<dcp::Marker, dcpomatic::DCPTime> marker) {
+		int const x1 = floor(pixels_per_unit_time * marker.second.get());
+		auto const width = text_width(name);
+		auto const y = allocate(x1, x1 + label_to_end_gap + width);
+		components.push_back(MarkerLayoutComponent{MarkerLayoutComponent::Type::LEFT, x1, y, marker.first, marker.second});
+		components.push_back(MarkerLayoutComponent{MarkerLayoutComponent::Type::LABEL, x1 + label_to_end_gap, width, y, name});
+		components.push_back(MarkerLayoutComponent{MarkerLayoutComponent::Type::LINE, x1, x1 + label_to_end_gap, y});
+	};
+
+	auto layout_right = [&](string name, pair<dcp::Marker, dcpomatic::DCPTime> marker) {
+		int const x2 = floor(pixels_per_unit_time * marker.second.get());
+		auto const width = text_width(name);
+		auto const y = allocate(x2 - label_to_end_gap - width, x2);
+		components.push_back(MarkerLayoutComponent{MarkerLayoutComponent::Type::RIGHT, x2, y, marker.first, marker.second});
+		components.push_back(MarkerLayoutComponent{MarkerLayoutComponent::Type::LABEL, x2 - label_to_end_gap - width, width, y, name});
+		components.push_back(MarkerLayoutComponent{MarkerLayoutComponent::Type::LINE, x2 - label_to_end_gap, x2, y});
+	};
+
+	auto check_pair = [&](string name, dcp::Marker a, dcp::Marker b) {
+		auto fa = markers.find(a);
+		auto fb = markers.find(b);
+		if (fa != markers.end() && fb != markers.end()) {
+			layout_pair(name, *fa, *fb);
+		} else if (fa != markers.end()) {
+			layout_left(name, *fa);
+		} else if (fb != markers.end()) {
+			layout_right(name, *fb);
+		}
+	};
+
+	check_pair(_("RB"), dcp::Marker::FFOB, dcp::Marker::LFOB);
+	check_pair(_("TC"), dcp::Marker::FFTC, dcp::Marker::LFTC);
+	check_pair(_("IN"), dcp::Marker::FFOI, dcp::Marker::LFOI);
+	check_pair(_("EC"), dcp::Marker::FFEC, dcp::Marker::LFEC);
+	check_pair(_("MC"), dcp::Marker::FFMC, dcp::Marker::LFMC);
+
+	return components;
+}
+
+
+bool
+AllocationRow::allocate(int x1, int x2)
+{
+	auto overlaps = [](pair<int, int> a, pair<int, int> b) {
+		return max(a.first, b.first) <= min(a.second, b.second);
+	};
+
+	if (std::none_of(_allocated.begin(), _allocated.end(), std::bind(overlaps, pair{x1, x2}, _1))) {
+		_allocated.push_back({x1, x2});
+		return true;
+	}
+
+	return false;
+}
+
diff --git a/src/lib/layout_markers.h b/src/lib/layout_markers.h
new file mode 100644
index 000000000..5c615f20e
--- /dev/null
+++ b/src/lib/layout_markers.h
@@ -0,0 +1,93 @@
+/*
+    Copyright (C) 2025 Carl Hetherington <cth@carlh.net>
+
+    This file is part of DCP-o-matic.
+
+    DCP-o-matic is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    DCP-o-matic is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with DCP-o-matic.  If not, see <http://www.gnu.org/licenses/>.
+
+*/
+
+
+#include "dcpomatic_time.h"
+#include <dcp/types.h>
+#include <string>
+#include <utility>
+#include <vector>
+
+
+class MarkerLayoutComponent
+{
+public:
+	enum class Type {
+		LEFT,
+		RIGHT,
+		LINE,
+		LABEL
+	};
+
+	MarkerLayoutComponent(Type type_, int x1_, int y_, dcp::Marker marker_, dcpomatic::DCPTime t1_)
+		: type(type_)
+		, x1(x1_)
+		, y(y_)
+		, marker(marker_)
+		, t1(t1_)
+	{}
+
+	MarkerLayoutComponent(Type type_, int x1_, int x2_, int y_)
+		: type(type_)
+		, x1(x1_)
+		, x2(x2_)
+		, y(y_)
+	{}
+
+	MarkerLayoutComponent(Type type_, int x1_, int width, int y_, std::string text_)
+		: type(type_)
+		, x1(x1_)
+		, x2(x1_ + width)
+		, y(y_)
+		, text(text_)
+	{}
+
+	Type type = Type::LINE;
+	int x1 = 0;
+	int x2 = 0;
+	int y = 0;
+	boost::optional<dcp::Marker> marker;
+	dcpomatic::DCPTime t1;
+	std::string text;
+};
+
+
+class AllocationRow
+{
+public:
+	AllocationRow() = default;
+
+	/** @return true if allocation succeded, otherwise false */
+	bool allocate(int x1, int x2);
+
+private:
+	std::vector<std::pair<int, int>> _allocated;
+};
+
+
+std::vector<MarkerLayoutComponent> layout_markers(
+	std::map<dcp::Marker, dcpomatic::DCPTime> const& markers,
+	int width_in_pixels,
+	dcpomatic::DCPTime width_in_time,
+	int label_to_end_gap,
+	int outside_label_gap,
+	std::function<int (std::string)> text_width
+);
+
diff --git a/src/lib/wscript b/src/lib/wscript
index ce93b5824..2e7b0339c 100644
--- a/src/lib/wscript
+++ b/src/lib/wscript
@@ -157,6 +157,7 @@ sources = """
           kdm_recipient.cc
           kdm_with_metadata.cc
           kdm_util.cc
+          layout_markers.cc
           log.cc
           log_entry.cc
           make_dcp.cc