Restore lights in RTAO, at least on the CPU side + cleanups

Author: devshgraphicsprogramming

examples_tests/22.RaytracedAO/InstanceDataPerCamera.glsl

@@ -6,7 +6,7 @@
 struct InstanceDataPerCamera
 {
     mat4 MVP;
-    mat4x3 NormalMatrix;
+    mat4x3 NormalMatAndFlags;
 };
 
 #endif

examples_tests/22.RaytracedAO/common.glsl

@@ -3,10 +3,55 @@
 
 #define MAX_ACCUMULATED_SAMPLES (1024*1024)
 
+
 #ifdef __cplusplus
 	#define mat4 irr::core::matrix4SIMD
 	#define mat4x3 irr::core::matrix3x4SIMD
 #endif
 
 
+struct SLight
+{
+	#ifdef __cplusplus
+	SLight() : obb() {}
+	SLight(const SLight& other) : obb(other.obb) {}
+	SLight(const irr::core::aabbox3df& bbox, const irr::core::matrix3x4SIMD& tform) : SLight()
+	{
+		auto extent = bbox.getExtent();
+		obb.setScale(irr::core::vectorSIMDf(extent.X,extent.Y,extent.Z));
+		obb.setTranslation(irr::core::vectorSIMDf(bbox.MinEdge.X,bbox.MinEdge.Y,bbox.MinEdge.Z));
+
+		obb = irr::core::concatenateBFollowedByA(tform,obb);
+	}
+	
+	inline SLight& operator=(SLight&& other) noexcept
+	{
+		std::swap(obb, other.obb);
+
+		return *this;
+	}
+
+	// also known as an upper bound on lumens put into the scene
+	inline float computeFluxBound(const irr::core::vectorSIMDf& radiance) const
+	{
+		const irr::core::vectorSIMDf rec709LumaCoeffs(0.2126f, 0.7152f, 0.0722f, 0.f);
+		const auto unitHemisphereArea = 2.f*irr::core::PI<float>();
+				
+		const auto unitBoxScale = obb.getScale();
+		const float obbArea = 2.f*(unitBoxScale.x*unitBoxScale.y+unitBoxScale.x*unitBoxScale.z+unitBoxScale.y*unitBoxScale.z);
+				
+		return irr::core::dot(radiance,rec709LumaCoeffs).x*unitHemisphereArea*obbArea;
+	}
+	#endif
+
+	mat4x3 obb; // needs row_major qualifier
+};
+
+
+#ifdef __cplusplus
+	#undef mat4
+	#undef mat4x3
+#endif
+
+
 #endif