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ac11a14509
Co-authored-by: Lars Mueller <appgurulars@gmx.de> Co-authored-by: jordan4ibanez <jordan4ibanez@users.noreply.github.com> Co-authored-by: sfan5 <sfan5@live.de> Co-authored-by: SmallJoker <SmallJoker@users.noreply.github.com>
696 lines
23 KiB
C++
696 lines
23 KiB
C++
// Minetest
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// SPDX-License-Identifier: LGPL-2.1-or-later
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#include "CGLTFMeshFileLoader.h"
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#include "coreutil.h"
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#include "CSkinnedMesh.h"
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#include "ISkinnedMesh.h"
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#include "irrTypes.h"
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#include "IReadFile.h"
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#include "matrix4.h"
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#include "path.h"
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#include "quaternion.h"
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#include "vector3d.h"
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#include "os.h"
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#include "tiniergltf.hpp"
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#include <array>
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#include <cstddef>
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#include <cstring>
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#include <limits>
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#include <memory>
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#include <optional>
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#include <stdexcept>
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#include <utility>
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#include <variant>
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#include <vector>
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namespace irr {
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/* Notes on the coordinate system.
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*
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* glTF uses a right-handed coordinate system where +Z is the
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* front-facing axis, and Irrlicht uses a left-handed coordinate
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* system where -Z is the front-facing axis.
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* We convert between them by mirroring the mesh across the X axis.
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* Doing this correctly requires negating the Z coordinate on
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* vertex positions and normals, and reversing the winding order
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* of the vertex indices.
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*/
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// Right-to-left handedness conversions
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template <typename T>
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static inline T convertHandedness(const T &t);
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template <>
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core::vector3df convertHandedness(const core::vector3df &p)
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{
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return core::vector3df(p.X, p.Y, -p.Z);
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}
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namespace scene {
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using SelfType = CGLTFMeshFileLoader;
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template <class T>
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SelfType::Accessor<T>
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SelfType::Accessor<T>::sparseIndices(const tiniergltf::GlTF &model,
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const tiniergltf::AccessorSparseIndices &indices,
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const std::size_t count)
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{
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const auto &view = model.bufferViews->at(indices.bufferView);
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const auto byteStride = view.byteStride.value_or(indices.elementSize());
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const auto &buffer = model.buffers->at(view.buffer);
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const auto source = buffer.data.data() + view.byteOffset + indices.byteOffset;
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return SelfType::Accessor<T>(source, byteStride, count);
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}
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template <class T>
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SelfType::Accessor<T>
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SelfType::Accessor<T>::sparseValues(const tiniergltf::GlTF &model,
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const tiniergltf::AccessorSparseValues &values,
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const std::size_t count,
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const std::size_t defaultByteStride)
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{
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const auto &view = model.bufferViews->at(values.bufferView);
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const auto byteStride = view.byteStride.value_or(defaultByteStride);
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const auto &buffer = model.buffers->at(view.buffer);
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const auto source = buffer.data.data() + view.byteOffset + values.byteOffset;
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return SelfType::Accessor<T>(source, byteStride, count);
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}
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template <class T>
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SelfType::Accessor<T>
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SelfType::Accessor<T>::base(const tiniergltf::GlTF &model, std::size_t accessorIdx)
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{
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const auto &accessor = model.accessors->at(accessorIdx);
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if (!accessor.bufferView.has_value()) {
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return Accessor<T>(accessor.count);
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}
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const auto &view = model.bufferViews->at(accessor.bufferView.value());
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const auto byteStride = view.byteStride.value_or(accessor.elementSize());
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const auto &buffer = model.buffers->at(view.buffer);
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const auto source = buffer.data.data() + view.byteOffset + accessor.byteOffset;
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return Accessor<T>(source, byteStride, accessor.count);
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}
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template <class T>
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SelfType::Accessor<T>
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SelfType::Accessor<T>::make(const tiniergltf::GlTF &model, std::size_t accessorIdx)
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{
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const auto &accessor = model.accessors->at(accessorIdx);
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if (accessor.componentType != getComponentType() || accessor.type != getType())
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throw std::runtime_error("invalid accessor");
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const auto base = Accessor<T>::base(model, accessorIdx);
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if (accessor.sparse.has_value()) {
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std::vector<T> vec(accessor.count);
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for (std::size_t i = 0; i < accessor.count; ++i) {
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vec[i] = base.get(i);
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}
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const auto overriddenCount = accessor.sparse->count;
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const auto indicesAccessor = ([&]() -> AccessorVariant<u8, u16, u32> {
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switch (accessor.sparse->indices.componentType) {
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case tiniergltf::AccessorSparseIndices::ComponentType::UNSIGNED_BYTE:
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return Accessor<u8>::sparseIndices(model, accessor.sparse->indices, overriddenCount);
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case tiniergltf::AccessorSparseIndices::ComponentType::UNSIGNED_SHORT:
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return Accessor<u16>::sparseIndices(model, accessor.sparse->indices, overriddenCount);
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case tiniergltf::AccessorSparseIndices::ComponentType::UNSIGNED_INT:
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return Accessor<u32>::sparseIndices(model, accessor.sparse->indices, overriddenCount);
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}
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throw std::logic_error("invalid enum value");
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})();
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const auto valuesAccessor = Accessor<T>::sparseValues(model,
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accessor.sparse->values, overriddenCount,
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accessor.bufferView.has_value()
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? model.bufferViews->at(*accessor.bufferView).byteStride.value_or(accessor.elementSize())
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: accessor.elementSize());
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for (std::size_t i = 0; i < overriddenCount; ++i) {
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u32 index;
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std::visit([&](auto &&acc) { index = acc.get(i); }, indicesAccessor);
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if (index >= accessor.count)
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throw std::runtime_error("index out of bounds");
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vec[index] = valuesAccessor.get(i);
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}
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return Accessor<T>(vec, accessor.count);
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}
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return base;
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}
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#define ACCESSOR_TYPES(T, U, V) \
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template <> \
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constexpr tiniergltf::Accessor::Type SelfType::Accessor<T>::getType() \
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{ \
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return tiniergltf::Accessor::Type::U; \
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} \
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template <> \
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constexpr tiniergltf::Accessor::ComponentType SelfType::Accessor<T>::getComponentType() \
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{ \
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return tiniergltf::Accessor::ComponentType::V; \
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}
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#define VEC_ACCESSOR_TYPES(T, U, N) \
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template <> \
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constexpr tiniergltf::Accessor::Type SelfType::Accessor<std::array<T, N>>::getType() \
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{ \
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return tiniergltf::Accessor::Type::VEC##N; \
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} \
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template <> \
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constexpr tiniergltf::Accessor::ComponentType SelfType::Accessor<std::array<T, N>>::getComponentType() \
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{ \
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return tiniergltf::Accessor::ComponentType::U; \
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} \
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template <> \
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std::array<T, N> SelfType::rawget(const char *ptr) \
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{ \
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std::array<T, N> res; \
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for (int i = 0; i < N; ++i) \
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res[i] = rawget<T>(ptr + sizeof(T) * i); \
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return res; \
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}
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#define ACCESSOR_PRIMITIVE(T, U) \
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ACCESSOR_TYPES(T, SCALAR, U) \
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VEC_ACCESSOR_TYPES(T, U, 2) \
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VEC_ACCESSOR_TYPES(T, U, 3) \
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VEC_ACCESSOR_TYPES(T, U, 4)
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ACCESSOR_PRIMITIVE(f32, FLOAT)
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ACCESSOR_PRIMITIVE(u8, UNSIGNED_BYTE)
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ACCESSOR_PRIMITIVE(u16, UNSIGNED_SHORT)
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ACCESSOR_PRIMITIVE(u32, UNSIGNED_INT)
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ACCESSOR_TYPES(core::vector3df, VEC3, FLOAT)
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template <class T>
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T SelfType::Accessor<T>::get(std::size_t i) const
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{
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// Buffer-based accessor: Read directly from the buffer.
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if (std::holds_alternative<BufferSource>(source)) {
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const auto bufsrc = std::get<BufferSource>(source);
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return rawget<T>(bufsrc.ptr + i * bufsrc.byteStride);
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}
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// Array-based accessor (used for sparse accessors): Read from array.
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if (std::holds_alternative<std::vector<T>>(source)) {
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return std::get<std::vector<T>>(source)[i];
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}
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// Default-initialized accessor.
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// We differ slightly from glTF here in that
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// we default-initialize quaternions and matrices properly,
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// but this does not cause any discrepancies for valid glTF models.
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std::get<std::tuple<>>(source);
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return T();
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}
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template <typename T>
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T SelfType::rawget(const char *ptr)
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{
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T dest;
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std::memcpy(&dest, ptr, sizeof(dest));
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#ifdef __BIG_ENDIAN__
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return os::Byteswap::byteswap(dest);
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#else
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return dest;
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#endif
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}
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// Note that these "more specialized templates" should win.
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template <>
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core::matrix4 SelfType::rawget(const char *ptr)
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{
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core::matrix4 mat;
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for (u8 i = 0; i < 16; ++i) {
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mat[i] = rawget<f32>(ptr + i * sizeof(f32));
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}
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return mat;
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}
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template <>
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core::vector3df SelfType::rawget(const char *ptr)
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{
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return core::vector3df(
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rawget<f32>(ptr),
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rawget<f32>(ptr + sizeof(f32)),
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rawget<f32>(ptr + 2 * sizeof(f32)));
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}
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template <>
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core::quaternion SelfType::rawget(const char *ptr)
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{
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return core::quaternion(
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rawget<f32>(ptr),
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rawget<f32>(ptr + sizeof(f32)),
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rawget<f32>(ptr + 2 * sizeof(f32)),
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rawget<f32>(ptr + 3 * sizeof(f32)));
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}
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template <std::size_t N>
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SelfType::NormalizedValuesAccessor<N>
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SelfType::createNormalizedValuesAccessor(
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const tiniergltf::GlTF &model,
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const std::size_t accessorIdx)
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{
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const auto &acc = model.accessors->at(accessorIdx);
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switch (acc.componentType) {
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case tiniergltf::Accessor::ComponentType::UNSIGNED_BYTE:
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return Accessor<std::array<u8, N>>::make(model, accessorIdx);
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case tiniergltf::Accessor::ComponentType::UNSIGNED_SHORT:
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return Accessor<std::array<u16, N>>::make(model, accessorIdx);
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case tiniergltf::Accessor::ComponentType::FLOAT:
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return Accessor<std::array<f32, N>>::make(model, accessorIdx);
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default:
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throw std::runtime_error("invalid component type");
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}
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}
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template <std::size_t N>
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std::array<f32, N> SelfType::getNormalizedValues(
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const NormalizedValuesAccessor<N> &accessor,
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const std::size_t i)
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{
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std::array<f32, N> values;
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if (std::holds_alternative<Accessor<std::array<u8, N>>>(accessor)) {
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const auto u8s = std::get<Accessor<std::array<u8, N>>>(accessor).get(i);
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for (u8 i = 0; i < N; ++i)
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values[i] = static_cast<f32>(u8s[i]) / std::numeric_limits<u8>::max();
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} else if (std::holds_alternative<Accessor<std::array<u16, N>>>(accessor)) {
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const auto u16s = std::get<Accessor<std::array<u16, N>>>(accessor).get(i);
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for (u8 i = 0; i < N; ++i)
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values[i] = static_cast<f32>(u16s[i]) / std::numeric_limits<u16>::max();
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} else {
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values = std::get<Accessor<std::array<f32, N>>>(accessor).get(i);
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for (u8 i = 0; i < N; ++i) {
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if (values[i] < 0 || values[i] > 1)
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throw std::runtime_error("invalid normalized value");
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}
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}
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return values;
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}
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/**
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* The most basic portion of the code base. This tells irllicht if this file has a .gltf extension.
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*/
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bool SelfType::isALoadableFileExtension(
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const io::path& filename) const
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{
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return core::hasFileExtension(filename, "gltf");
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}
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/**
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* Entry point into loading a GLTF model.
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*/
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IAnimatedMesh* SelfType::createMesh(io::IReadFile* file)
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{
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if (file->getSize() <= 0) {
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return nullptr;
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}
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std::optional<tiniergltf::GlTF> model = tryParseGLTF(file);
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if (!model.has_value()) {
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return nullptr;
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}
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if (!(model->buffers.has_value()
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&& model->bufferViews.has_value()
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&& model->accessors.has_value()
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&& model->meshes.has_value()
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&& model->nodes.has_value())) {
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os::Printer::log("glTF loader", "missing required fields", ELL_ERROR);
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return nullptr;
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}
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auto *mesh = new CSkinnedMesh();
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MeshExtractor parser(std::move(model.value()), mesh);
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try {
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parser.loadNodes();
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} catch (std::runtime_error &e) {
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os::Printer::log("glTF loader", e.what(), ELL_ERROR);
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mesh->drop();
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return nullptr;
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}
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if (model->images.has_value())
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os::Printer::log("glTF loader", "embedded images are not supported", ELL_WARNING);
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return mesh;
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}
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static void transformVertices(std::vector<video::S3DVertex> &vertices, const core::matrix4 &transform)
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{
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for (auto &vertex : vertices) {
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// Apply scaling, rotation and rotation (in that order) to the position.
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transform.transformVect(vertex.Pos);
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// For the normal, we do not want to apply the translation.
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// TODO note that this also applies scaling; the Irrlicht method is misnamed.
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transform.rotateVect(vertex.Normal);
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// Renormalize (length might have been affected by scaling).
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vertex.Normal.normalize();
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}
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}
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static void checkIndices(const std::vector<u16> &indices, const std::size_t nVerts)
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{
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for (u16 index : indices) {
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if (index >= nVerts)
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throw std::runtime_error("index out of bounds");
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}
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}
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static std::vector<u16> generateIndices(const std::size_t nVerts)
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{
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std::vector<u16> indices(nVerts);
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for (std::size_t i = 0; i < nVerts; i += 3) {
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// Reverse winding order per triangle
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indices[i] = i + 2;
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indices[i + 1] = i + 1;
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indices[i + 2] = i;
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}
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return indices;
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}
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/**
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* Load up the rawest form of the model. The vertex positions and indices.
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* Documentation: https://registry.khronos.org/glTF/specs/2.0/glTF-2.0.html#meshes
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* If material is undefined, then a default material MUST be used.
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*/
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void SelfType::MeshExtractor::loadMesh(
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const std::size_t meshIdx,
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ISkinnedMesh::SJoint *parent) const
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{
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for (std::size_t pi = 0; pi < getPrimitiveCount(meshIdx); ++pi) {
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const auto &primitive = m_gltf_model.meshes->at(meshIdx).primitives.at(pi);
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auto vertices = getVertices(primitive);
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if (!vertices.has_value())
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continue; // "When positions are not specified, client implementations SHOULD skip primitive’s rendering"
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// Excludes the max value for consistency.
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if (vertices->size() >= std::numeric_limits<u16>::max())
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throw std::runtime_error("too many vertices");
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// Apply the global transform along the parent chain.
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transformVertices(*vertices, parent->GlobalMatrix);
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auto maybeIndices = getIndices(primitive);
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std::vector<u16> indices;
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if (maybeIndices.has_value()) {
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indices = std::move(*maybeIndices);
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checkIndices(indices, vertices->size());
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} else {
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// Non-indexed geometry
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indices = generateIndices(vertices->size());
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}
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m_irr_model->addMeshBuffer(
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new SSkinMeshBuffer(std::move(*vertices), std::move(indices)));
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if (primitive.material.has_value()) {
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const auto &material = m_gltf_model.materials->at(*primitive.material);
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if (material.pbrMetallicRoughness.has_value()) {
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const auto &texture = material.pbrMetallicRoughness->baseColorTexture;
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if (texture.has_value()) {
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const auto meshbufNr = m_irr_model->getMeshBufferCount() - 1;
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m_irr_model->setTextureSlot(meshbufNr, static_cast<u32>(texture->index));
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}
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}
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}
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}
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}
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// Base transformation between left & right handed coordinate systems.
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// This just inverts the Z axis.
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static const core::matrix4 leftToRight = core::matrix4(
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1, 0, 0, 0,
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0, 1, 0, 0,
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0, 0, -1, 0,
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0, 0, 0, 1
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);
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static const core::matrix4 rightToLeft = leftToRight;
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static core::matrix4 loadTransform(const tiniergltf::Node::Matrix &m)
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{
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// Note: Under the hood, this casts these doubles to floats.
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return core::matrix4(
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m[0], m[1], m[2], m[3],
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m[4], m[5], m[6], m[7],
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m[8], m[9], m[10], m[11],
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m[12], m[13], m[14], m[15]);
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}
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static core::matrix4 loadTransform(const tiniergltf::Node::TRS &trs)
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{
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const auto &trans = trs.translation;
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const auto &rot = trs.rotation;
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const auto &scale = trs.scale;
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core::matrix4 transMat;
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transMat.setTranslation(core::vector3df(trans[0], trans[1], trans[2]));
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core::matrix4 rotMat = core::quaternion(rot[0], rot[1], rot[2], rot[3]).getMatrix();
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core::matrix4 scaleMat;
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scaleMat.setScale(core::vector3df(scale[0], scale[1], scale[2]));
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return transMat * rotMat * scaleMat;
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}
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static core::matrix4 loadTransform(std::optional<std::variant<tiniergltf::Node::Matrix, tiniergltf::Node::TRS>> transform) {
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if (!transform.has_value()) {
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return core::matrix4();
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}
|
||
core::matrix4 mat = std::visit([](const auto &t) { return loadTransform(t); }, *transform);
|
||
return rightToLeft * mat * leftToRight;
|
||
}
|
||
|
||
void SelfType::MeshExtractor::loadNode(
|
||
const std::size_t nodeIdx,
|
||
ISkinnedMesh::SJoint *parent) const
|
||
{
|
||
const auto &node = m_gltf_model.nodes->at(nodeIdx);
|
||
auto *joint = m_irr_model->addJoint(parent);
|
||
const core::matrix4 transform = loadTransform(node.transform);
|
||
joint->LocalMatrix = transform;
|
||
joint->GlobalMatrix = parent ? parent->GlobalMatrix * joint->LocalMatrix : joint->LocalMatrix;
|
||
if (node.name.has_value()) {
|
||
joint->Name = node.name->c_str();
|
||
}
|
||
if (node.mesh.has_value()) {
|
||
loadMesh(*node.mesh, joint);
|
||
}
|
||
if (node.children.has_value()) {
|
||
for (const auto &child : *node.children) {
|
||
loadNode(child, joint);
|
||
}
|
||
}
|
||
}
|
||
|
||
void SelfType::MeshExtractor::loadNodes() const
|
||
{
|
||
std::vector<bool> isChild(m_gltf_model.nodes->size());
|
||
for (const auto &node : *m_gltf_model.nodes) {
|
||
if (!node.children.has_value())
|
||
continue;
|
||
for (const auto &child : *node.children) {
|
||
isChild[child] = true;
|
||
}
|
||
}
|
||
// Load all nodes that aren't children.
|
||
// Children will be loaded by their parent nodes.
|
||
for (std::size_t i = 0; i < m_gltf_model.nodes->size(); ++i) {
|
||
if (!isChild[i]) {
|
||
loadNode(i, nullptr);
|
||
}
|
||
}
|
||
}
|
||
|
||
/**
|
||
* Extracts GLTF mesh indices.
|
||
*/
|
||
std::optional<std::vector<u16>> SelfType::MeshExtractor::getIndices(
|
||
const tiniergltf::MeshPrimitive &primitive) const
|
||
{
|
||
const auto accessorIdx = primitive.indices;
|
||
if (!accessorIdx.has_value())
|
||
return std::nullopt; // non-indexed geometry
|
||
|
||
const auto accessor = ([&]() -> AccessorVariant<u8, u16, u32> {
|
||
const auto &acc = m_gltf_model.accessors->at(*accessorIdx);
|
||
switch (acc.componentType) {
|
||
case tiniergltf::Accessor::ComponentType::UNSIGNED_BYTE:
|
||
return Accessor<u8>::make(m_gltf_model, *accessorIdx);
|
||
case tiniergltf::Accessor::ComponentType::UNSIGNED_SHORT:
|
||
return Accessor<u16>::make(m_gltf_model, *accessorIdx);
|
||
case tiniergltf::Accessor::ComponentType::UNSIGNED_INT:
|
||
return Accessor<u32>::make(m_gltf_model, *accessorIdx);
|
||
default:
|
||
throw std::runtime_error("invalid component type");
|
||
}
|
||
})();
|
||
const auto count = std::visit([](auto &&a) { return a.getCount(); }, accessor);
|
||
|
||
std::vector<u16> indices;
|
||
for (std::size_t i = 0; i < count; ++i) {
|
||
// TODO (low-priority, maybe never) also reverse winding order based on determinant of global transform
|
||
// FIXME this hack also reverses triangle draw order
|
||
std::size_t elemIdx = count - i - 1; // reverse index order
|
||
u16 index;
|
||
// Note: glTF forbids the max value for each component type.
|
||
if (std::holds_alternative<Accessor<u8>>(accessor)) {
|
||
index = std::get<Accessor<u8>>(accessor).get(elemIdx);
|
||
if (index == std::numeric_limits<u8>::max())
|
||
throw std::runtime_error("invalid index");
|
||
} else if (std::holds_alternative<Accessor<u16>>(accessor)) {
|
||
index = std::get<Accessor<u16>>(accessor).get(elemIdx);
|
||
if (index == std::numeric_limits<u16>::max())
|
||
throw std::runtime_error("invalid index");
|
||
} else if (std::holds_alternative<Accessor<u32>>(accessor)) {
|
||
u32 indexWide = std::get<Accessor<u32>>(accessor).get(elemIdx);
|
||
// Use >= here for consistency.
|
||
if (indexWide >= std::numeric_limits<u16>::max())
|
||
throw std::runtime_error("index too large (>= 65536)");
|
||
index = static_cast<u16>(indexWide);
|
||
}
|
||
indices.push_back(index);
|
||
}
|
||
|
||
return indices;
|
||
}
|
||
|
||
/**
|
||
* Create a vector of video::S3DVertex (model data) from a mesh & primitive index.
|
||
*/
|
||
std::optional<std::vector<video::S3DVertex>> SelfType::MeshExtractor::getVertices(
|
||
const tiniergltf::MeshPrimitive &primitive) const
|
||
{
|
||
const auto &attributes = primitive.attributes;
|
||
const auto positionAccessorIdx = attributes.position;
|
||
if (!positionAccessorIdx.has_value()) {
|
||
// "When positions are not specified, client implementations SHOULD skip primitive's rendering"
|
||
return std::nullopt;
|
||
}
|
||
|
||
std::vector<video::S3DVertex> vertices;
|
||
const auto vertexCount = m_gltf_model.accessors->at(*positionAccessorIdx).count;
|
||
vertices.resize(vertexCount);
|
||
copyPositions(*positionAccessorIdx, vertices);
|
||
|
||
const auto normalAccessorIdx = attributes.normal;
|
||
if (normalAccessorIdx.has_value()) {
|
||
copyNormals(normalAccessorIdx.value(), vertices);
|
||
}
|
||
// TODO verify that the automatic normal recalculation done in Minetest indeed works correctly
|
||
|
||
const auto &texcoords = attributes.texcoord;
|
||
if (texcoords.has_value()) {
|
||
const auto tCoordAccessorIdx = texcoords->at(0);
|
||
copyTCoords(tCoordAccessorIdx, vertices);
|
||
}
|
||
|
||
return vertices;
|
||
}
|
||
|
||
/**
|
||
* Get the amount of meshes that a model contains.
|
||
*/
|
||
std::size_t SelfType::MeshExtractor::getMeshCount() const
|
||
{
|
||
return m_gltf_model.meshes->size();
|
||
}
|
||
|
||
/**
|
||
* Get the amount of primitives that a mesh in a model contains.
|
||
*/
|
||
std::size_t SelfType::MeshExtractor::getPrimitiveCount(
|
||
const std::size_t meshIdx) const
|
||
{
|
||
return m_gltf_model.meshes->at(meshIdx).primitives.size();
|
||
}
|
||
|
||
/**
|
||
* Streams vertex positions raw data into usable buffer via reference.
|
||
* Buffer: ref Vector<video::S3DVertex>
|
||
*/
|
||
void SelfType::MeshExtractor::copyPositions(
|
||
const std::size_t accessorIdx,
|
||
std::vector<video::S3DVertex>& vertices) const
|
||
{
|
||
const auto accessor = Accessor<core::vector3df>::make(m_gltf_model, accessorIdx);
|
||
for (std::size_t i = 0; i < accessor.getCount(); i++) {
|
||
vertices[i].Pos = convertHandedness(accessor.get(i));
|
||
}
|
||
}
|
||
|
||
/**
|
||
* Streams normals raw data into usable buffer via reference.
|
||
* Buffer: ref Vector<video::S3DVertex>
|
||
*/
|
||
void SelfType::MeshExtractor::copyNormals(
|
||
const std::size_t accessorIdx,
|
||
std::vector<video::S3DVertex>& vertices) const
|
||
{
|
||
const auto accessor = Accessor<core::vector3df>::make(m_gltf_model, accessorIdx);
|
||
for (std::size_t i = 0; i < accessor.getCount(); ++i) {
|
||
vertices[i].Normal = convertHandedness(accessor.get(i));
|
||
}
|
||
}
|
||
|
||
/**
|
||
* Streams texture coordinate raw data into usable buffer via reference.
|
||
* Buffer: ref Vector<video::S3DVertex>
|
||
*/
|
||
void SelfType::MeshExtractor::copyTCoords(
|
||
const std::size_t accessorIdx,
|
||
std::vector<video::S3DVertex>& vertices) const
|
||
{
|
||
const auto accessor = createNormalizedValuesAccessor<2>(m_gltf_model, accessorIdx);
|
||
const auto count = std::visit([](auto &&a) { return a.getCount(); }, accessor);
|
||
for (std::size_t i = 0; i < count; ++i) {
|
||
const auto vals = getNormalizedValues(accessor, i);
|
||
vertices[i].TCoords = core::vector2df(vals[0], vals[1]);
|
||
}
|
||
}
|
||
|
||
/**
|
||
* This is where the actual model's GLTF file is loaded and parsed by tiniergltf.
|
||
*/
|
||
std::optional<tiniergltf::GlTF> SelfType::tryParseGLTF(io::IReadFile* file)
|
||
{
|
||
auto size = file->getSize();
|
||
if (size < 0) // this can happen if `ftell` fails
|
||
return std::nullopt;
|
||
std::unique_ptr<char[]> buf(new char[size + 1]);
|
||
if (file->read(buf.get(), size) != static_cast<std::size_t>(size))
|
||
return std::nullopt;
|
||
// We probably don't need this, but add it just to be sure.
|
||
buf[size] = '\0';
|
||
Json::CharReaderBuilder builder;
|
||
const std::unique_ptr<Json::CharReader> reader(builder.newCharReader());
|
||
Json::Value json;
|
||
JSONCPP_STRING err;
|
||
if (!reader->parse(buf.get(), buf.get() + size, &json, &err)) {
|
||
return std::nullopt;
|
||
}
|
||
try {
|
||
return tiniergltf::GlTF(json);
|
||
} catch (const std::runtime_error &e) {
|
||
os::Printer::log("glTF loader", e.what(), ELL_ERROR);
|
||
return std::nullopt;
|
||
} catch (const std::out_of_range &e) {
|
||
os::Printer::log("glTF loader", e.what(), ELL_ERROR);
|
||
return std::nullopt;
|
||
}
|
||
}
|
||
|
||
} // namespace scene
|
||
|
||
} // namespace irr
|
||
|