Libraries: Move to Userland/Libraries/

1 files changed, 234 insertions, 0 deletions

diff --git a/Userland/Libraries/LibGfx/Path.cpp b/Userland/Libraries/LibGfx/Path.cpp
new file mode 100644
index 0000000000..5fe2bb2f63
--- /dev/null
+++ b/Userland/Libraries/LibGfx/Path.cpp
@@ -0,0 +1,234 @@
+/*
+ * Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <AK/Function.h>
+#include <AK/HashTable.h>
+#include <AK/QuickSort.h>
+#include <AK/StringBuilder.h>
+#include <LibGfx/Painter.h>
+#include <LibGfx/Path.h>
+
+namespace Gfx {
+
+void Path::close()
+{
+    if (m_segments.size() <= 1)
+        return;
+
+    invalidate_split_lines();
+
+    auto& last_point = m_segments.last().point();
+
+    for (ssize_t i = m_segments.size() - 1; i >= 0; --i) {
+        auto& segment = m_segments[i];
+        if (segment.type() == Segment::Type::MoveTo) {
+            if (last_point == segment.point())
+                return;
+            append_segment<LineSegment>(segment.point());
+            return;
+        }
+    }
+}
+
+void Path::close_all_subpaths()
+{
+    if (m_segments.size() <= 1)
+        return;
+
+    invalidate_split_lines();
+
+    Optional<FloatPoint> cursor, start_of_subpath;
+    bool is_first_point_in_subpath { false };
+
+    for (auto& segment : m_segments) {
+        switch (segment.type()) {
+        case Segment::Type::MoveTo: {
+            if (cursor.has_value() && !is_first_point_in_subpath) {
+                // This is a move from a subpath to another
+                // connect the two ends of this subpath before
+                // moving on to the next one
+                ASSERT(start_of_subpath.has_value());
+
+                append_segment<MoveSegment>(cursor.value());
+                append_segment<LineSegment>(start_of_subpath.value());
+            }
+            is_first_point_in_subpath = true;
+            cursor = segment.point();
+            break;
+        }
+        case Segment::Type::LineTo:
+        case Segment::Type::QuadraticBezierCurveTo:
+        case Segment::Type::EllipticalArcTo:
+            if (is_first_point_in_subpath) {
+                start_of_subpath = cursor;
+                is_first_point_in_subpath = false;
+            }
+            cursor = segment.point();
+            break;
+        case Segment::Type::Invalid:
+            ASSERT_NOT_REACHED();
+            break;
+        }
+    }
+}
+
+String Path::to_string() const
+{
+    StringBuilder builder;
+    builder.append("Path { ");
+    for (auto& segment : m_segments) {
+        switch (segment.type()) {
+        case Segment::Type::MoveTo:
+            builder.append("MoveTo");
+            break;
+        case Segment::Type::LineTo:
+            builder.append("LineTo");
+            break;
+        case Segment::Type::QuadraticBezierCurveTo:
+            builder.append("QuadraticBezierCurveTo");
+            break;
+        case Segment::Type::EllipticalArcTo:
+            builder.append("EllipticalArcTo");
+            break;
+        case Segment::Type::Invalid:
+            builder.append("Invalid");
+            break;
+        }
+        builder.appendf("(%s", segment.point().to_string().characters());
+
+        switch (segment.type()) {
+        case Segment::Type::QuadraticBezierCurveTo:
+            builder.append(", ");
+            builder.append(static_cast<const QuadraticBezierCurveSegment&>(segment).through().to_string());
+            break;
+        case Segment::Type::EllipticalArcTo: {
+            auto& arc = static_cast<const EllipticalArcSegment&>(segment);
+            builder.appendf(", %s, %s, %f, %f, %f",
+                arc.radii().to_string().characters(),
+                arc.center().to_string().characters(),
+                arc.x_axis_rotation(),
+                arc.theta_1(),
+                arc.theta_delta());
+            break;
+        }
+        default:
+            break;
+        }
+
+        builder.append(") ");
+    }
+    builder.append("}");
+    return builder.to_string();
+}
+
+void Path::segmentize_path()
+{
+    Vector<SplitLineSegment> segments;
+    float min_x = 0;
+    float min_y = 0;
+    float max_x = 0;
+    float max_y = 0;
+
+    auto add_point_to_bbox = [&](const Gfx::FloatPoint& point) {
+        float x = point.x();
+        float y = point.y();
+        min_x = min(min_x, x);
+        min_y = min(min_y, y);
+        max_x = max(max_x, x);
+        max_y = max(max_y, y);
+    };
+
+    auto add_line = [&](const auto& p0, const auto& p1) {
+        float ymax = p0.y(), ymin = p1.y(), x_of_ymin = p1.x(), x_of_ymax = p0.x();
+        auto slope = p0.x() == p1.x() ? 0 : ((float)(p0.y() - p1.y())) / ((float)(p0.x() - p1.x()));
+        if (p0.y() < p1.y()) {
+            swap(ymin, ymax);
+            swap(x_of_ymin, x_of_ymax);
+        }
+
+        segments.append({ FloatPoint(p0.x(), p0.y()),
+            FloatPoint(p1.x(), p1.y()),
+            slope == 0 ? 0 : 1 / slope,
+            x_of_ymin,
+            ymax, ymin, x_of_ymax });
+
+        add_point_to_bbox(p1);
+    };
+
+    FloatPoint cursor { 0, 0 };
+    bool first = true;
+
+    for (auto& segment : m_segments) {
+        switch (segment.type()) {
+        case Segment::Type::MoveTo:
+            if (first) {
+                min_x = segment.point().x();
+                min_y = segment.point().y();
+                max_x = segment.point().x();
+                max_y = segment.point().y();
+            } else {
+                add_point_to_bbox(segment.point());
+            }
+            cursor = segment.point();
+            break;
+        case Segment::Type::LineTo: {
+            add_line(cursor, segment.point());
+            cursor = segment.point();
+            break;
+        }
+        case Segment::Type::QuadraticBezierCurveTo: {
+            auto& control = static_cast<QuadraticBezierCurveSegment&>(segment).through();
+            Painter::for_each_line_segment_on_bezier_curve(control, cursor, segment.point(), [&](const FloatPoint& p0, const FloatPoint& p1) {
+                add_line(p0, p1);
+            });
+            cursor = segment.point();
+            break;
+        }
+        case Segment::Type::EllipticalArcTo: {
+            auto& arc = static_cast<EllipticalArcSegment&>(segment);
+            Painter::for_each_line_segment_on_elliptical_arc(cursor, arc.point(), arc.center(), arc.radii(), arc.x_axis_rotation(), arc.theta_1(), arc.theta_delta(), [&](const FloatPoint& p0, const FloatPoint& p1) {
+                add_line(p0, p1);
+            });
+            cursor = segment.point();
+            break;
+        }
+        case Segment::Type::Invalid:
+            ASSERT_NOT_REACHED();
+        }
+
+        first = false;
+    }
+
+    // sort segments by ymax
+    quick_sort(segments, [](const auto& line0, const auto& line1) {
+        return line1.maximum_y < line0.maximum_y;
+    });
+
+    m_split_lines = move(segments);
+    m_bounding_box = Gfx::FloatRect { min_x, min_y, max_x - min_x, max_y - min_y };
+}
+
+}