Add scaleLinear unit test with mixed unsigned types

The integer promotion rules that apply to this case can trigger overflow issues with the previous `scaleLinear` code, though are correctly handled by the new update.
lairworks · Mar 5, 2025 · 40d4f21 · 40d4f21
1 parent 7acdda4
commit 40d4f21
Showing 1 changed file with 8 additions and 0 deletions.
diff --git a/test/Math/MathUtils.test.cpp b/test/Math/MathUtils.test.cpp
@@ -124,6 +124,14 @@ TEST(MathUtils, scaleLinearForwardUint32toUint8) {
 	EXPECT_EQ(uint8_t{255}, NAS2D::scaleLinear(uint32_t{10000}, uint32_t{0}, uint32_t{10000}, uint8_t{0}, uint8_t{255}));
 }
 
+TEST(MathUtils, scaleLinearReverseUint32toUint8) {
+	EXPECT_EQ(uint8_t{255}, NAS2D::scaleLinear(uint32_t{0}, uint32_t{0}, uint32_t{10000}, uint8_t{255}, uint8_t{0}));
+	EXPECT_EQ(uint8_t{191}, NAS2D::scaleLinear(uint32_t{2500}, uint32_t{0}, uint32_t{10000}, uint8_t{255}, uint8_t{0}));
+	EXPECT_EQ(uint8_t{127}, NAS2D::scaleLinear(uint32_t{5000}, uint32_t{0}, uint32_t{10000}, uint8_t{255}, uint8_t{0}));
+	EXPECT_EQ(uint8_t{63}, NAS2D::scaleLinear(uint32_t{7500}, uint32_t{0}, uint32_t{10000}, uint8_t{255}, uint8_t{0}));
+	EXPECT_EQ(uint8_t{0}, NAS2D::scaleLinear(uint32_t{10000}, uint32_t{0}, uint32_t{10000}, uint8_t{255}, uint8_t{0}));
+}
+
 TEST(MathUtils, scaleLinearFloatFahrenheitToCelsius) {
 	// Fahrenheit to Celsius
 	EXPECT_NEAR(-18.33333f, NAS2D::scaleLinear(-1.0f, 32.0f, 212.0f, 0.0f, 100.0f), 0.0001f);