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Diffstat (limited to 'source/blender/functions/FN_generic_span.hh')
-rw-r--r-- | source/blender/functions/FN_generic_span.hh | 158 |
1 files changed, 158 insertions, 0 deletions
diff --git a/source/blender/functions/FN_generic_span.hh b/source/blender/functions/FN_generic_span.hh new file mode 100644 index 00000000000..31b67dd3d70 --- /dev/null +++ b/source/blender/functions/FN_generic_span.hh @@ -0,0 +1,158 @@ +/* + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software Foundation, + * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. + */ + +#pragma once + +/** \file + * \ingroup fn + */ + +#include "BLI_span.hh" + +#include "FN_cpp_type.hh" + +namespace blender::fn { + +/** + * A generic span. It behaves just like a blender::Span<T>, but the type is only known at run-time. + */ +class GSpan { + private: + const CPPType *type_; + const void *data_; + int64_t size_; + + public: + GSpan(const CPPType &type, const void *buffer, int64_t size) + : type_(&type), data_(buffer), size_(size) + { + BLI_assert(size >= 0); + BLI_assert(buffer != nullptr || size == 0); + BLI_assert(type.pointer_has_valid_alignment(buffer)); + } + + GSpan(const CPPType &type) : GSpan(type, nullptr, 0) + { + } + + template<typename T> + GSpan(Span<T> array) + : GSpan(CPPType::get<T>(), static_cast<const void *>(array.data()), array.size()) + { + } + + const CPPType &type() const + { + return *type_; + } + + bool is_empty() const + { + return size_ == 0; + } + + int64_t size() const + { + return size_; + } + + const void *data() const + { + return data_; + } + + const void *operator[](int64_t index) const + { + BLI_assert(index < size_); + return POINTER_OFFSET(data_, type_->size() * index); + } + + template<typename T> Span<T> typed() const + { + BLI_assert(type_->is<T>()); + return Span<T>(static_cast<const T *>(data_), size_); + } +}; + +/** + * A generic mutable span. It behaves just like a blender::MutableSpan<T>, but the type is only + * known at run-time. + */ +class GMutableSpan { + private: + const CPPType *type_; + void *data_; + int64_t size_; + + public: + GMutableSpan(const CPPType &type, void *buffer, int64_t size) + : type_(&type), data_(buffer), size_(size) + { + BLI_assert(size >= 0); + BLI_assert(buffer != nullptr || size == 0); + BLI_assert(type.pointer_has_valid_alignment(buffer)); + } + + GMutableSpan(const CPPType &type) : GMutableSpan(type, nullptr, 0) + { + } + + template<typename T> + GMutableSpan(MutableSpan<T> array) + : GMutableSpan(CPPType::get<T>(), static_cast<void *>(array.begin()), array.size()) + { + } + + operator GSpan() const + { + return GSpan(*type_, data_, size_); + } + + const CPPType &type() const + { + return *type_; + } + + bool is_empty() const + { + return size_ == 0; + } + + int64_t size() const + { + return size_; + } + + void *data() const + { + return data_; + } + + void *operator[](int64_t index) const + { + BLI_assert(index >= 0); + BLI_assert(index < size_); + return POINTER_OFFSET(data_, type_->size() * index); + } + + template<typename T> MutableSpan<T> typed() const + { + BLI_assert(type_->is<T>()); + return MutableSpan<T>(static_cast<T *>(data_), size_); + } +}; + +} // namespace blender::fn |