Create aabb.hlsl

Author: devshgraphicsprogramming

include/nbl/builtin/hlsl/shapes/aabb.hlsl

@@ -0,0 +1,68 @@
+// Copyright (C) 2018-2022 - DevSH Graphics Programming Sp. z O.O.
+// This file is part of the "Nabla Engine".
+// For conditions of distribution and use, see copyright notice in nabla.h
+#ifndef _NBL_BUILTIN_HLSL_SHAPES_AABB_INCLUDED_
+#define _NBL_BUILTIN_HLSL_SHAPES_AABB_INCLUDED_
+
+#include <nbl/builtin/hlsl/format/decode.hlsl>
+
+
+namespace nbl
+{
+namespace hlsl
+{
+namespace shapes
+{
+
+struct AABB_t
+{
+    //
+    void addPoint(const float3 pt)
+    {
+        minVx = min(pt, minVx);
+        maxVx = max(pt, maxVx);
+    }
+    //
+    float3 getExtent()
+    {
+        return maxVx - minVx;
+    }
+
+    //
+    float getVolume()
+    {
+        const float3 extent = AABB_t::getExtent();
+        return extent.x * extent.y * extent.z;
+    }
+
+    // returns the corner of the AABB which has the most positive dot product
+    float3 getFarthestPointInFront(const float3 plane)
+    {
+        return lerp(maxVx, minVx, plane<float3(0.f,0.f,0.f));
+    }
+
+    float3 minVx;
+    float3 maxVx;
+};
+
+struct nbl_glsl_shapes_CompressedAABB_t
+{
+    //
+    AABB_t decompress()
+    {
+        AABB_t retval;
+        retval.minVx = decodeRGB18E7S3(minVx18E7S3);
+        retval.maxVx = decodeRGB18E7S3(maxVx18E7S3);
+        return retval;
+    }
+
+    uint2 minVx18E7S3;
+    uint2 maxVx18E7S3;
+};
+
+
+}
+}
+}
+
+#endif