初始提交: UE5.3项目基础框架

Plugins/CesiumForUnreal/Source/CesiumRuntime/Private/CesiumTransforms.cpp

@@ -0,0 +1,30 @@
+// Copyright 2020-2024 CesiumGS, Inc. and Contributors
+
+#include "CesiumTransforms.h"
+
+const double CesiumTransforms::metersToCentimeters = 100.0;
+const double CesiumTransforms::centimetersToMeters = 0.01;
+
+// Scale Cesium's meters up to Unreal's centimeters.
+const glm::dmat4x4 CesiumTransforms::scaleToUnrealWorld =
+    glm::dmat4x4(glm::dmat3x3(metersToCentimeters));
+
+// Scale down Unreal's centimeters into Cesium's meters.
+const glm::dmat4x4 CesiumTransforms::scaleToCesium =
+    glm::dmat4x4(glm::dmat3x3(centimetersToMeters));
+
+// We're initializing with a static function instead of inline to avoid an
+// internal compiler error in MSVC v14.27.29110.
+static glm::dmat4 createUnrealToOrFromCesium() {
+  return glm::dmat4x4(
+      glm::dvec4(1.0, 0.0, 0.0, 0.0),
+      glm::dvec4(0.0, -1.0, 0.0, 0.0),
+      glm::dvec4(0.0, 0.0, 1.0, 0.0),
+      glm::dvec4(0.0, 0.0, 0.0, 1.0));
+}
+
+// Transform Cesium's right-handed, Z-up coordinate system to Unreal's
+// left-handed, Z-up coordinate system by inverting the Y coordinate. This same
+// transformation can also go the other way.
+const glm::dmat4x4 CesiumTransforms::unrealToOrFromCesium =
+    createUnrealToOrFromCesium();