feat(desktop): P17 清晨/黄昏光照精修（暖色天际 + 过渡窗口参数化，分数小时平滑）

1 files changed, 29 insertions, 15 deletions

diff --git a/src/LivingVillage.Desktop.Tests/PrototypeTests.fs b/src/LivingVillage.Desktop.Tests/PrototypeTests.fs
index b8f23a0..5a153b1 100644
--- a/src/LivingVillage.Desktop.Tests/PrototypeTests.fs
+++ b/src/LivingVillage.Desktop.Tests/PrototypeTests.fs
@@ -858,21 +858,35 @@ type PrototypeTests () =
         Assert.AreEqual<float32>(1.0f, (atHour 0).Blend)
         Assert.AreEqual<float32>(1.0f, (atHour 2).Blend)
 
-        // Dawn ramp: 4:00 -> 6:00 goes night -> day, monotonic.
-        let dawnStart = (atHour 4).Blend
-        let dawnMid = (M6Presentation.lightingAtTick (int64 5 * ticksPerHour)).Blend
-        let dawnEnd = (atHour 6).Blend
-        Assert.AreEqual<float32>(1.0f, dawnStart)
-        Assert.AreEqual<float32>(0.5f, dawnMid)
-        Assert.AreEqual<float32>(0.0f, dawnEnd)
-
-        // Dusk ramp 20:00 -> 22:00 goes day -> night monotonically.
-        let duskStart = (atHour 20).Blend
-        let duskMid = (M6Presentation.lightingAtTick (int64 21 * ticksPerHour)).Blend
-        let duskEnd = (atHour 22).Blend
-        Assert.AreEqual<float32>(0.0f, duskStart)
-        Assert.AreEqual<float32>(0.5f, duskMid)
-        Assert.AreEqual<float32>(1.0f, duskEnd)
+        // P17 window: dawn 4:00 -> 6:30 goes night -> day, monotonic (fractional hours).
+        let dawnMidTick = int64 5 * ticksPerHour + ticksPerHour / 4L // 5:15
+        let dawnEndTick = int64 6 * ticksPerHour + ticksPerHour / 2L // 6:30
+        Assert.AreEqual<float32>(1.0f, (atHour 4).Blend)
+        Assert.AreEqual<float32>(0.5f, (M6Presentation.lightingAtTick dawnMidTick).Blend)
+        Assert.AreEqual<float32>(0.0f, (M6Presentation.lightingAtTick dawnEndTick).Blend)
+
+        // Dusk ramp 19:30 -> 22:00 goes day -> night monotonically.
+        let duskStartTick = int64 19 * ticksPerHour + ticksPerHour / 2L // 19:30
+        let duskMidTick = int64 20 * ticksPerHour + ticksPerHour * 3L / 4L // 20:45
+        Assert.AreEqual<float32>(0.0f, (M6Presentation.lightingAtTick duskStartTick).Blend)
+        Assert.AreEqual<float32>(0.5f, (M6Presentation.lightingAtTick duskMidTick).Blend)
+        Assert.AreEqual<float32>(1.0f, (atHour 22).Blend)
+
+        // Blue hour: the transition lingers past 6:00 and starts before 20:00.
+        Assert.IsTrue((atHour 6).Blend > 0.0f && (atHour 6).Blend < 0.5f)
+        Assert.IsTrue((atHour 20).Blend > 0.0f && (atHour 20).Blend < 0.5f)
+
+        // Golden-hour warmth peaks mid-dawn/mid-dusk and vanishes at noon/midnight.
+        Assert.AreEqual<float32>(0.0f, (atHour 12).SkyWarmth)
+        Assert.AreEqual<float32>(0.0f, (atHour 0).SkyWarmth)
+        Assert.AreEqual<float32>(1.0f, (M6Presentation.lightingAtTick dawnMidTick).SkyWarmth)
+        Assert.AreEqual<float32>(1.0f, (M6Presentation.lightingAtTick duskMidTick).SkyWarmth)
+        Assert.IsTrue((atHour 5).SkyWarmth > 0.5f)
+        Assert.IsTrue((atHour 21).SkyWarmth > 0.5f)
+        // The warm shift pushes the sky redder and less blue than the plain blend.
+        let warmDawn = atHour 5
+        Assert.IsTrue(warmDawn.Background.R > (M6Presentation.backgroundAtBlend warmDawn.Blend).R)
+        Assert.IsTrue(warmDawn.Background.B < (M6Presentation.backgroundAtBlend warmDawn.Blend).B)
 
         // Determinism without randomness.
         let once = atHour 13