feat(selection): port retail offscreen target indicator

tests/AcDream.App.Tests/UI/Layout/VividTargetIndicatorLayoutTests.cs

@@ -37,4 +37,78 @@ public sealed class VividTargetIndicatorLayoutTests
         Assert.Equal(new Vector2(8f, 8f), layout.RootPosition);
         Assert.Equal(new Vector2(66f, 87f), layout.RootSize);
     }
+
+    [Fact]
+    public void ProjectionHasNoDistanceOrWorldDrawVisibilityGate()
+    {
+        Matrix4x4 projection = Matrix4x4.CreatePerspectiveFieldOfView(
+            MathF.PI / 2f, 4f / 3f, 0.1f, 100f);
+
+        VividTargetProjection result = VividTargetIndicatorController.ComputeProjection(
+            new Vector3(0f, 0f, -1_000_000f),
+            1f,
+            Matrix4x4.Identity,
+            projection,
+            new Vector2(800f, 600f));
+
+        Assert.Equal(VividTargetProjectionStatus.OnScreen, result.Status);
+        Assert.InRange((result.RectMin.X + result.RectMax.X) * 0.5f, 399.9f, 400.1f);
+        Assert.InRange((result.RectMin.Y + result.RectMax.Y) * 0.5f, 299.9f, 300.1f);
+    }
+
+    [Theory]
+    [InlineData(100f, 0f, -10f, 0f, 6u)]
+    [InlineData(0f, 100f, -10f, 90f, 9u)]
+    [InlineData(-100f, 0f, -10f, 180f, 11u)]
+    [InlineData(0f, -100f, -10f, 270f, 8u)]
+    public void OffScreenDirectionMatchesRetailViewerAxes(
+        float x, float y, float z, float expectedAngle, uint expectedImageEnum)
+    {
+        Matrix4x4 projection = Matrix4x4.CreatePerspectiveFieldOfView(
+            MathF.PI / 2f, 4f / 3f, 0.1f, 100f);
+
+        VividTargetProjection result = VividTargetIndicatorController.ComputeProjection(
+            new Vector3(x, y, z),
+            1f,
+            Matrix4x4.Identity,
+            projection,
+            new Vector2(800f, 600f));
+
+        Assert.Equal(VividTargetProjectionStatus.OffScreen, result.Status);
+        Assert.Equal(expectedAngle, result.AngleDegrees, precision: 3);
+        Assert.Equal(expectedImageEnum,
+            VividTargetIndicatorController.SelectOffScreenImageEnum(result.AngleDegrees));
+    }
+
+    [Theory]
+    [InlineData(0f, 768f, 288f)]
+    [InlineData(90f, 388f, 8f)]
+    [InlineData(180f, 8f, 288f)]
+    [InlineData(270f, 388f, 568f)]
+    public void OffScreenImageClampsToRetailEightPixelEdge(
+        float angle, float expectedLeft, float expectedTop)
+    {
+        Vector2 position = VividTargetIndicatorController.ComputeOffScreenPosition(
+            angle,
+            new Vector2(800f, 600f),
+            new Vector2(24f, 24f));
+
+        Assert.Equal(expectedLeft, position.X, precision: 3);
+        Assert.Equal(expectedTop, position.Y, precision: 3);
+    }
+
+    [Theory]
+    [InlineData(0f, 6u)]
+    [InlineData(22.999f, 6u)]
+    [InlineData(23f, 7u)]
+    [InlineData(68f, 9u)]
+    [InlineData(113f, 12u)]
+    [InlineData(158f, 11u)]
+    [InlineData(203f, 10u)]
+    [InlineData(248f, 8u)]
+    [InlineData(293f, 5u)]
+    [InlineData(338f, 6u)]
+    public void DirectionImageUsesRetailSectorBoundaries(float angle, uint expected)
+        => Assert.Equal(expected,
+            VividTargetIndicatorController.SelectOffScreenImageEnum(angle));
 }