ImathHash.h : Added file to allow using Imath types with unordered_map

Author: danieldresser-ie

include/IECore/ImathHash.h

@@ -0,0 +1,93 @@
+//////////////////////////////////////////////////////////////////////////
+//
+//  Copyright (c) 2023, Image Engine Design Inc. All rights reserved.
+//
+//  Redistribution and use in source and binary forms, with or without
+//  modification, are permitted provided that the following conditions are
+//  met:
+//
+//     * Redistributions of source code must retain the above copyright
+//       notice, this list of conditions and the following disclaimer.
+//
+//     * Redistributions in binary form must reproduce the above copyright
+//       notice, this list of conditions and the following disclaimer in the
+//       documentation and/or other materials provided with the distribution.
+//
+//     * Neither the name of Image Engine Design nor the names of any
+//       other contributors to this software may be used to endorse or
+//       promote products derived from this software without specific prior
+//       written permission.
+//
+//  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
+//  IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+//  THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+//  PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+//  CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+//  EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+//  PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+//  PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+//  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+//  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+//  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+//
+//////////////////////////////////////////////////////////////////////////
+
+#ifndef IE_CORE_IMATHHASH_H
+#define IE_CORE_IMATHHASH_H
+
+IECORE_PUSH_DEFAULT_VISIBILITY
+#include "OpenEXR/half.h"
+#include "OpenEXR/ImathBox.h"
+#include "OpenEXR/ImathColor.h"
+#include "OpenEXR/ImathMatrix.h"
+#include "OpenEXR/ImathQuat.h"
+#include "OpenEXR/ImathVec.h"
+IECORE_POP_DEFAULT_VISIBILITY
+
+namespace IECore
+{
+
+namespace Detail
+{
+
+template <typename T>
+struct PodHash
+{
+	size_t operator()( const T &x ) const
+	{
+		return std::hash<std::string_view>()( std::string_view( (char*)&x, sizeof( T ) ) );
+	}
+};
+
+} // namespace Detail
+
+} // namespace IECore
+
+namespace std
+{
+
+template <> struct hash<half> : public IECore::Detail::PodHash<half> { };
+template <> struct hash<Imath::V2f> : public IECore::Detail::PodHash<Imath::V2f> { };
+template <> struct hash<Imath::V2i> : public IECore::Detail::PodHash<Imath::V2i> { };
+template <> struct hash<Imath::V2d> : public IECore::Detail::PodHash<Imath::V2d> { };
+template <> struct hash<Imath::V3f> : public IECore::Detail::PodHash<Imath::V3f> { };
+template <> struct hash<Imath::V3i> : public IECore::Detail::PodHash<Imath::V3i> { };
+template <> struct hash<Imath::V3d> : public IECore::Detail::PodHash<Imath::V3d> { };
+template <> struct hash<Imath::Color3f> : public IECore::Detail::PodHash<Imath::Color3f> { };
+template <> struct hash<Imath::Color4f> : public IECore::Detail::PodHash<Imath::Color4f> { };
+template <> struct hash<Imath::Quatf> : public IECore::Detail::PodHash<Imath::Quatf> { };
+template <> struct hash<Imath::Quatd> : public IECore::Detail::PodHash<Imath::Quatd> { };
+template <> struct hash<Imath::M33f> : public IECore::Detail::PodHash<Imath::M33f> { };
+template <> struct hash<Imath::M33d> : public IECore::Detail::PodHash<Imath::M33d> { };
+template <> struct hash<Imath::M44f> : public IECore::Detail::PodHash<Imath::M44f> { };
+template <> struct hash<Imath::M44d> : public IECore::Detail::PodHash<Imath::M44d> { };
+template <> struct hash<Imath::Box2i> : public IECore::Detail::PodHash<Imath::Box2i> { };
+template <> struct hash<Imath::Box3i> : public IECore::Detail::PodHash<Imath::Box3i> { };
+template <> struct hash<Imath::Box2f> : public IECore::Detail::PodHash<Imath::Box2f> { };
+template <> struct hash<Imath::Box3f> : public IECore::Detail::PodHash<Imath::Box3f> { };
+template <> struct hash<Imath::Box2d> : public IECore::Detail::PodHash<Imath::Box2d> { };
+template <> struct hash<Imath::Box3d> : public IECore::Detail::PodHash<Imath::Box3d> { };
+
+} // namespace std
+
+#endif // IE_CORE_IMATHHASH_H