From df8eed957662a6cff9e31cc59387933cb587f501 Mon Sep 17 00:00:00 2001
From: 23rd <23rd@vivaldi.net>
Date: Sun, 29 Nov 2020 03:19:22 +0300
Subject: [PATCH] Added implementation of blobs painter.

---
 CMakeLists.txt               |  2 ++
 ui/effects/animation_value.h | 46 ++++++++++++++++++++++++++
 ui/paint/blobs.cpp           | 63 ++++++++++++++++++++++++++++++++++++
 ui/paint/blobs.h             | 50 ++++++++++++++++++++++++++++
 4 files changed, 161 insertions(+)
 create mode 100644 ui/paint/blobs.cpp
 create mode 100644 ui/paint/blobs.h

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 3d0597b..47285df 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -68,6 +68,8 @@ PRIVATE
     ui/layers/layer_widget.h
     ui/paint/blob.cpp
     ui/paint/blob.h
+    ui/paint/blobs.cpp
+    ui/paint/blobs.h
     ui/platform/linux/ui_window_linux.cpp
     ui/platform/linux/ui_window_linux.h
     ui/platform/linux/ui_utility_linux.cpp
diff --git a/ui/effects/animation_value.h b/ui/effects/animation_value.h
index dc5d530..93110ce 100644
--- a/ui/effects/animation_value.h
+++ b/ui/effects/animation_value.h
@@ -404,4 +404,50 @@ private:
 
 };
 
+class continuous_value {
+public:
+	continuous_value() = default;
+	continuous_value(float64 duration) : _duration(duration) {
+	}
+	void start(float64 to, float64 duration) {
+		_to = to;
+		_delta = (_to - _cur) / duration;
+	}
+	void start(float64 to) {
+		start(to, _duration);
+	}
+	void reset() {
+		_to = _cur = _delta = 0.;
+	}
+
+	float64 current() const {
+		return _cur;
+	}
+	float64 to() const {
+		return _to;
+	}
+	float64 delta() const {
+		return _delta;
+	}
+	void update(crl::time dt, Fn<void(float64 &)> &&callback = nullptr) {
+		if (_to != _cur) {
+			_cur += _delta * dt;
+			if ((_to != _cur) && ((_delta > 0) == (_cur > _to))) {
+				_cur = _to;
+			}
+			if (callback) {
+				callback(_cur);
+			}
+		}
+	}
+
+private:
+	float64 _duration = 0.;
+	float64 _to = 0.;
+
+	float64 _cur = 0.;
+	float64 _delta = 0.;
+
+};
+
 } // namespace anim
diff --git a/ui/paint/blobs.cpp b/ui/paint/blobs.cpp
new file mode 100644
index 0000000..a235725
--- /dev/null
+++ b/ui/paint/blobs.cpp
@@ -0,0 +1,63 @@
+// This file is part of Desktop App Toolkit,
+// a set of libraries for developing nice desktop applications.
+//
+// For license and copyright information please follow this link:
+// https://github.com/desktop-app/legal/blob/master/LEGAL
+//
+#include "ui/paint/blobs.h"
+
+#include "ui/painter.h"
+
+namespace Ui::Paint {
+
+Blobs::Blobs(
+	std::vector<BlobData> blobDatas,
+	float levelDuration,
+	float maxLevel)
+: _maxLevel(maxLevel)
+, _blobDatas(blobDatas)
+, _levelValue(levelDuration) {
+	init();
+}
+
+void Blobs::init() {
+	for (const auto &data : _blobDatas) {
+		auto blob = Paint::BlobBezier(data.segmentsCount, data.minScale);
+		blob.setRadius(data.minRadius, data.maxRadius);
+		_blobs.push_back(std::move(blob));
+	}
+}
+
+float Blobs::maxRadius() const {
+	const auto maxOfRadiuses = [](const BlobData data) {
+		return std::max(data.maxRadius, data.minRadius);
+	};
+	const auto max = *ranges::max_element(
+		_blobDatas,
+		std::less<>(),
+		maxOfRadiuses);
+	return maxOfRadiuses(max);
+}
+
+void Blobs::setLevel(float value) {
+	const auto to = std::min(_maxLevel, value) / _maxLevel;
+	_levelValue.start(to);
+}
+
+void Blobs::paint(Painter &p, const QBrush &brush) {
+	const auto dt = crl::now() - _lastUpdateTime;
+	_levelValue.update((dt > 20) ? 17 : dt);
+
+	const auto opacity = p.opacity();
+	for (auto i = 0; i < _blobs.size(); i++) {
+		_blobs[i].update(_levelValue.current(), _blobDatas[i].speedScale);
+		const auto alpha = _blobDatas[i].alpha;
+		if (alpha != 1.) {
+			p.setOpacity(opacity * alpha);
+		}
+		_blobs[i].paint(p, brush);
+	}
+	_lastUpdateTime = crl::now();
+}
+
+} // namespace Ui::Paint
diff --git a/ui/paint/blobs.h b/ui/paint/blobs.h
new file mode 100644
index 0000000..6d53eab
--- /dev/null
+++ b/ui/paint/blobs.h
@@ -0,0 +1,50 @@
+// This file is part of Desktop App Toolkit,
+// a set of libraries for developing nice desktop applications.
+//
+// For license and copyright information please follow this link:
+// https://github.com/desktop-app/legal/blob/master/LEGAL
+//
+#pragma once
+
+#include "ui/effects/animation_value.h"
+#include "ui/paint/blob.h"
+
+class Painter;
+
+namespace Ui::Paint {
+
+class Blobs final {
+public:
+	struct BlobData {
+		int segmentsCount = 0;
+		float minScale = 0;
+		float minRadius = 0;
+		float maxRadius = 0;
+		float speedScale = 0;
+		float alpha = 0;
+	};
+
+	Blobs(
+		std::vector<BlobData> blobDatas,
+		float levelDuration,
+		float maxLevel);
+
+	void setLevel(float value);
+	void paint(Painter &p, const QBrush &brush);
+
+	[[nodiscard]] float maxRadius() const;
+
+private:
+	void init();
+
+	const float _maxLevel;
+
+	std::vector<BlobData> _blobDatas;
+	std::vector<BlobBezier> _blobs;
+
+	crl::time _lastUpdateTime = 0;
+	anim::continuous_value _levelValue;
+
+};
+
+} // namespace Ui::Paint