Added support for unsigned int accessors (#245)

* Added Unsigned Int to CreateAccessors()

* Added UnsignedIntAccessor class

* Added UnsignedIntAccessor class function implementations

* Oops

* Update src/ObjLoading/XModel/Gltf/Internal/GltfAccessor.cpp

Co-authored-by: Jan <Laupetin@users.noreply.github.com>

* Fixed ReadElement() using incorrect elementSize

---------

Co-authored-by: Jan <Laupetin@users.noreply.github.com>

src/ObjLoading/XModel/Gltf/GltfLoader.cpp

@@ -650,6 +650,8 @@ namespace
                     m_accessors.emplace_back(std::make_unique<UnsignedByteAccessor>(bufferView, jAccessor.type, byteOffset, jAccessor.count));
                 else if (jAccessor.componentType == JsonAccessorComponentType::UNSIGNED_SHORT)
                     m_accessors.emplace_back(std::make_unique<UnsignedShortAccessor>(bufferView, jAccessor.type, byteOffset, jAccessor.count));
+                else if (jAccessor.componentType == JsonAccessorComponentType::UNSIGNED_INT)
+                    m_accessors.emplace_back(std::make_unique<UnsignedIntAccessor>(bufferView, jAccessor.type, byteOffset, jAccessor.count));
                 else
                     throw GltfLoadException(std::format("Accessor has unsupported component type {}", static_cast<unsigned>(jAccessor.componentType)));
             }

src/ObjLoading/XModel/Gltf/Internal/GltfAccessor.cpp

@@ -425,7 +425,115 @@ bool UnsignedShortAccessor::GetUnsignedVec4(const size_t index, unsigned (&out)[
         return false;
 
     uint16_t temp[4];
-    if (!m_buffer_view->ReadElement(temp, index, sizeof(uint8_t[4]), m_byte_offset))
+    if (!m_buffer_view->ReadElement(temp, index, sizeof(uint16_t[4]), m_byte_offset))
+        return false;
+
+    out[0] = static_cast<unsigned>(temp[0]);
+    out[1] = static_cast<unsigned>(temp[1]);
+    out[2] = static_cast<unsigned>(temp[2]);
+    out[3] = static_cast<unsigned>(temp[3]);
+
+    return true;
+}
+
+UnsignedIntAccessor::UnsignedIntAccessor(const BufferView* bufferView, const JsonAccessorType type, size_t byteOffset, const size_t count)
+    : m_buffer_view(bufferView),
+      m_type(type),
+      m_byte_offset(byteOffset),
+      m_count(count)
+{
+}
+
+std::optional<JsonAccessorType> UnsignedIntAccessor::GetType() const
+{
+    return m_type;
+}
+
+std::optional<JsonAccessorComponentType> UnsignedIntAccessor::GetComponentType() const
+{
+    return JsonAccessorComponentType::UNSIGNED_INT;
+}
+
+size_t UnsignedIntAccessor::GetCount() const
+{
+    return m_count;
+}
+
+bool UnsignedIntAccessor::GetFloatVec2(const size_t index, float (&out)[2]) const
+{
+    assert(m_type == JsonAccessorType::VEC2 || m_type == JsonAccessorType::VEC3 || m_type == JsonAccessorType::VEC4);
+    if (index >= m_count)
+        return false;
+
+    uint32_t temp[2];
+    if (!m_buffer_view->ReadElement(temp, index, sizeof(uint32_t[2]), m_byte_offset))
+        return false;
+
+    // Return as normalized value between 0 and 1
+    out[0] = static_cast<float>(temp[0]) / static_cast<float>(std::numeric_limits<uint32_t>::max());
+    out[1] = static_cast<float>(temp[1]) / static_cast<float>(std::numeric_limits<uint32_t>::max());
+
+    return true;
+}
+
+bool UnsignedIntAccessor::GetFloatVec3(const size_t index, float (&out)[3]) const
+{
+    assert(m_type == JsonAccessorType::VEC3 || m_type == JsonAccessorType::VEC4);
+    if (index >= m_count)
+        return false;
+
+    uint32_t temp[3];
+    if (!m_buffer_view->ReadElement(temp, index, sizeof(uint32_t[3]), m_byte_offset))
+        return false;
+
+    // Return as normalized value between 0 and 1
+    out[0] = static_cast<float>(temp[0]) / static_cast<float>(std::numeric_limits<uint32_t>::max());
+    out[1] = static_cast<float>(temp[1]) / static_cast<float>(std::numeric_limits<uint32_t>::max());
+    out[2] = static_cast<float>(temp[2]) / static_cast<float>(std::numeric_limits<uint32_t>::max());
+
+    return true;
+}
+
+bool UnsignedIntAccessor::GetFloatVec4(const size_t index, float (&out)[4]) const
+{
+    assert(m_type == JsonAccessorType::VEC4);
+    if (index >= m_count)
+        return false;
+
+    uint32_t temp[4];
+    if (!m_buffer_view->ReadElement(temp, index, sizeof(uint32_t[4]), m_byte_offset))
+        return false;
+
+    // Return as normalized value between 0 and 1
+    out[0] = static_cast<float>(temp[0]) / static_cast<float>(std::numeric_limits<uint32_t>::max());
+    out[1] = static_cast<float>(temp[1]) / static_cast<float>(std::numeric_limits<uint32_t>::max());
+    out[2] = static_cast<float>(temp[2]) / static_cast<float>(std::numeric_limits<uint32_t>::max());
+    out[3] = static_cast<float>(temp[3]) / static_cast<float>(std::numeric_limits<uint32_t>::max());
+
+    return true;
+}
+
+bool UnsignedIntAccessor::GetUnsigned(const size_t index, unsigned& out) const
+{
+    if (index >= m_count)
+        return false;
+
+    uint32_t temp;
+    if (!m_buffer_view->ReadElement(&temp, index, sizeof(uint32_t), m_byte_offset))
+        return false;
+
+    out = temp;
+    return true;
+}
+
+bool UnsignedIntAccessor::GetUnsignedVec4(const size_t index, unsigned (&out)[4]) const
+{
+    assert(m_type == JsonAccessorType::VEC4);
+    if (index >= m_count)
+        return false;
+
+    uint32_t temp[4];
+    if (!m_buffer_view->ReadElement(temp, index, sizeof(uint32_t[4]), m_byte_offset))
         return false;
 
     out[0] = static_cast<unsigned>(temp[0]);

src/ObjLoading/XModel/Gltf/Internal/GltfAccessor.h

@@ -130,4 +130,26 @@ namespace gltf
         size_t m_byte_offset;
         size_t m_count;
     };
+
+    class UnsignedIntAccessor final : public Accessor
+    {
+    public:
+        UnsignedIntAccessor(const BufferView* bufferView, JsonAccessorType type, size_t byteOffset, size_t count);
+
+        [[nodiscard]] std::optional<JsonAccessorType> GetType() const override;
+        [[nodiscard]] std::optional<JsonAccessorComponentType> GetComponentType() const override;
+        [[nodiscard]] size_t GetCount() const override;
+
+        [[nodiscard]] bool GetFloatVec2(size_t index, float (&out)[2]) const override;
+        [[nodiscard]] bool GetFloatVec3(size_t index, float (&out)[3]) const override;
+        [[nodiscard]] bool GetFloatVec4(size_t index, float (&out)[4]) const override;
+        [[nodiscard]] bool GetUnsigned(size_t index, unsigned& out) const override;
+        [[nodiscard]] bool GetUnsignedVec4(size_t index, unsigned (&out)[4]) const override;
+
+    private:
+        const BufferView* m_buffer_view;
+        JsonAccessorType m_type;
+        size_t m_byte_offset;
+        size_t m_count;
+    };
 } // namespace gltf