The document's own pixel budget, marching ants at screen resolution (12.11a)

tests/DocumentLimitsTests.cpp

@@ -0,0 +1,32 @@
+#include "Document/DocumentLimits.h"
+#include <QtTest>
+#include <unistd.h>
+
+// Swift 1.2.8's DocumentLimits: one surface, and a document's budget.
+class DocumentLimitsTests : public QObject {
+    Q_OBJECT
+private slots:
+    void theCeilingsAreSwifts();
+};
+
+void DocumentLimitsTests::theCeilingsAreSwifts()
+{
+    QCOMPARE(DocumentLimits::maxSide, 30'000);
+    QCOMPARE(DocumentLimits::maxSurfacePixels, qint64(200'000'000));
+    QCOMPARE(DocumentLimits::maxSurfaceMegapixels(), qint64(200));
+    QCOMPARE(DocumentLimits::maxSideText(), QString("30,000"));
+    // A quarter of memory, four bytes a pixel, clamped.
+    const qint64 memory = qint64(sysconf(_SC_PHYS_PAGES)) * qint64(sysconf(_SC_PAGE_SIZE));
+    const qint64 budget = std::clamp(memory / 16, qint64(200'000'000), qint64(800'000'000));
+    QCOMPARE(DocumentLimits::documentPixelBudget(), budget);
+    QCOMPARE(DocumentLimits::documentBudgetMegapixels(), budget / 1'000'000);
+    // Swift's 537 MP on 8 GB; the cap, the floor.
+    QCOMPARE(DocumentLimits::budgetFor(8ll << 30), qint64(536'870'912));
+    QCOMPARE(DocumentLimits::budgetFor(16ll << 30), qint64(800'000'000));
+    QCOMPARE(DocumentLimits::budgetFor(2ll << 30), qint64(200'000'000));
+    // Both stay under a square at the side limit.
+    QVERIFY(DocumentLimits::documentPixelBudget() < qint64(DocumentLimits::maxSide) * DocumentLimits::maxSide);
+}
+
+QTEST_GUILESS_MAIN(DocumentLimitsTests)
+#include "DocumentLimitsTests.moc"