Liquify keeps pixels sharp, Smudge without ghost copies, Blur's own Radius, the largest Smear commits (13.16, part one)

tests/LargeCanvasBrushTests.cpp

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+#include "BrushFixtures.h"
+#include "Document/EditorSession.h"
+#include "IO/ImageExporter.h"
+#include "SessionFixtures.h"
+#include <cmath>
+
+// Swift's LargeCanvasBrushTests: the largest Smear on a big canvas.
+namespace {
+// Eight coloured bands across a square canvas.
+void bands(EditorSession &session, int side)
+{
+    session.createDocument(side, side);
+    QImage image = BrushRaster::context(side, side, false);
+    {
+        QPainter painter(&image);
+        for (int band = 0; band < 8; ++band)
+            painter.fillRect(QRect(band * side / 8, 0, side / 8 + 1, side), QColor::fromRgbF(band / 7.0, 0.4, 1 - band / 7.0));
+    }
+    session.insert(ImportedImage(image, image, QStringLiteral("Bands")));
+    session.selectTool(NavigationTool::blur);
+    BrushSettings settings = session.brushSettings();
+    settings.diameter = 2000;
+    settings.hardness = 0.5;
+    session.setBrushSettings(settings);
+}
+
+void stroke(EditorSession &session, int side)
+{
+    const double y = side / 2.0;
+    session.beginBrush(QPointF(1000, y));
+    for (int step = 1; step <= 20; ++step)
+        session.continueBrush(QPointF(1000 + step * 100.0, y + (step % 3) * 40.0));
+    session.finishBrushImmediately();
+}
+}
+
+class LargeCanvasBrushTests : public QObject {
+    Q_OBJECT
+private slots:
+    void largestBrushCommits_data();
+    void largestBrushCommits();
+    void aThinnedCommitLandsAllTheWarpMoved();
+};
+
+void LargeCanvasBrushTests::largestBrushCommits_data()
+{
+    QTest::addColumn<BlurToolMode>("mode");
+    QTest::newRow("liquify") << BlurToolMode::liquify;
+    QTest::newRow("smudge") << BlurToolMode::smudge;
+}
+
+// The commit's tip runs past Size's 2000, once refused.
+void LargeCanvasBrushTests::largestBrushCommits()
+{
+    QFETCH(BlurToolMode, mode);
+    EditorSession session;
+    bands(session, 5000);
+    session.setBlurMode(mode);
+    const ImageIdentity before = session.activeLayer().value().asset.value().identity();
+    stroke(session, 5000);
+    QCOMPARE(session.brushError(), std::optional<QString>());
+    QVERIFY(session.activeLayer().value().asset.value().identity() != before);
+    QCOMPARE(session.history.undoName(), rawValue(mode));
+}
+
+// A point every twentieth of the tip covers the warp.
+void LargeCanvasBrushTests::aThinnedCommitLandsAllTheWarpMoved()
+{
+    EditorSession session;
+    bands(session, 400);
+    session.setBlurMode(BlurToolMode::liquify);
+    BrushSettings settings = session.brushSettings();
+    settings.diameter = 160;
+    settings.hardness = 1;
+    session.setBrushSettings(settings);
+    // Hard to its rim, ending a rim before a band.
+    session.beginBrush(QPointF(60, 200));
+    session.continueBrush(QPointF(273, 213));
+    const QImage live = session.warpStroke()->image().copy();
+    QCOMPARE(int(session.warpStroke()->points().size()), 54);
+    session.finishBrush();
+    const QImage landed = ImageExporter::render(session.projectSnapshot().value()).image.convertToFormat(QImage::Format_RGBA8888_Premultiplied);
+    int apart = 0;
+    for (int y = 0; y < 400; ++y)
+        apart += std::memcmp(landed.constScanLine(y), live.constScanLine(y), 400 * 4) != 0;
+    QCOMPARE(apart, 0);
+    QCOMPARE(session.history.undoName(), QString("Liquify"));
+    // A tight circle: chords between kept points stay close.
+    session.beginBrush(QPointF(260, 200));
+    for (int step = 1; step <= 72; ++step)
+        session.continueBrush(QPointF(200 + 60 * std::cos(step * M_PI / 36), 200 + 60 * std::sin(step * M_PI / 36)));
+    const QImage circled = session.warpStroke()->image().copy();
+    session.finishBrush();
+    const QImage turned = ImageExporter::render(session.projectSnapshot().value()).image.convertToFormat(QImage::Format_RGBA8888_Premultiplied);
+    for (int y = 0; y < 400; ++y)
+        apart += std::memcmp(turned.constScanLine(y), circled.constScanLine(y), 400 * 4) != 0;
+    QCOMPARE(apart, 0);
+}
+
+QTEST_GUILESS_MAIN(LargeCanvasBrushTests)
+#include "LargeCanvasBrushTests.moc"