CMakeLists.txt

@@ -76,6 +76,8 @@ elseif(CMAKE_SYSTEM_NAME STREQUAL "Linux")
     set(NB_TARGET_LINUX ON)
 endif()
 
+set(NB_GRAPHICS_API_OGL ON)
+
 if(NB_BUILD_TESTS)
     message(STATUS "Building tests")
     enable_testing()

engine/NBGraphics/CMakeLists.txt

@@ -56,6 +56,18 @@ toAbsolutePath(NB_GRAPHICS_INCLUDE
 set(NB_GRAPHICS_SOURCE ${NB_GRAPHICS_SOURCE} PARENT_SCOPE)
 set(NB_GRAPHICS_INCLUDE ${NB_GRAPHICS_INCLUDE} PARENT_SCOPE)
 
+if (NB_GRAPHICS_API_OGL)
+    toAbsolutePath(NB_GRAPHICS_API_OGL_SOURCE
+        ./src/OGL/Buffers.cpp
+    )
+    toAbsolutePath(NB_GRAPHICS_API_OGL_INCLUDE
+        ./include/NBGraphics/OGL/Buffers.hpp
+    )
+    set(NB_GRAPHICS_SOURCE ${NB_GRAPHICS_SOURCE} ${NB_GRAPHICS_API_OGL_SOURCE} PARENT_SCOPE)
+    set(NB_GRAPHICS_INCLUDE ${NB_GRAPHICS_INCLUDE} ${NB_GRAPHICS_API_OGL_SOURCE} PARENT_SCOPE)
+    add_library(NBGraphicsAPI_OGL ${NB_GRAPHICS_API_OGL_SOURCE})
+endif()
+
 add_library(NBGraphics 
     ${NB_GRAPHICS_SOURCE}
     ${GLAD_PATH}/src/glad.c
@@ -63,6 +75,11 @@ add_library(NBGraphics
 add_library(NBEngine::Graphics ALIAS NBGraphics)
 add_dependencies(NBGraphics NBCore)
 add_dependencies(NBGraphics glfw)
+
+if(NB_GRAPHICS_API_OGL)
+    add_dependencies(NBGraphics NBGraphicsAPI_OGL)
+endif()
+
 target_link_libraries(NBGraphics
     PUBLIC glfw
     PUBLIC NBCore    

engine/NBGraphics/include/NBGraphics/OGL/Buffers.hpp

@@ -0,0 +1,262 @@
+#pragma once
+#ifndef _NB_BUFFER
+#define _NB_BUFFER
+
+#include <NBGraphics/GLLoad.hpp>
+
+#include <string>
+
+#include <NBCore/Errors.hpp>
+#include <NBCore/Logger.hpp>
+#include <NBCore/Utils.hpp>
+
+#include <NBGraphics/OGLObjects.hpp>
+
+namespace nb {
+
+extern const ConstantMap <GLenum, std::string> BufferTypes;
+
+template<GLenum N>
+struct GLSLEnum;
+template<typename T>
+struct GLSLType;
+
+#define GLSLTypeTraits(type_, size_, value_) \
+template<>\
+struct GLSLEnum<value_> {\
+    using type = type_;\
+    static constexpr size_t size = size_;\
+    static constexpr GLenum value=value_;\
+};\
+template<>\
+struct GLSLType<type_> {\
+    using type = type_;\
+    static constexpr size_t size = size_;\
+    static constexpr GLenum value=value_;\
+};
+
+#define GLSLTypeEquivalence(original, newtype) \
+template<>\
+struct GLSLType<newtype> : public GLSLType<original> {};
+
+GLSLTypeTraits(uint8_t, 1, GL_UNSIGNED_BYTE);
+GLSLTypeTraits(uint16_t, 2, GL_UNSIGNED_SHORT);
+GLSLTypeTraits(uint32_t, 4, GL_UNSIGNED_INT);
+GLSLTypeTraits(int8_t, 1, GL_BYTE);
+GLSLTypeTraits(int16_t, 2, GL_SHORT);
+GLSLTypeTraits(int32_t, 4, GL_INT);
+GLSLTypeTraits(float, 4, GL_FLOAT);
+GLSLTypeTraits(double, 8, GL_DOUBLE);
+
+class BufferError : public Error<BufferError> {
+    protected:
+    using Base = Error<BufferError>;
+    
+    public:
+    using Base::Base;
+    enum Codes : unsigned int {
+        UNDEFINED,
+        DATA_OVERFLOW,
+        DATA_ERROR,
+        BAD_DATA_TYPE
+    };
+    static const std::string type;
+    static const ErrorCodeMap ErrorMessages;
+};
+
+class Buffer : public OpenGLObject {
+    protected:
+    using Codes = BufferError::Codes;
+    using OpenGLObject::_id;
+    GLenum _usage = GL_STATIC_DRAW;
+    size_t _size;
+    virtual GLuint declare() override {
+        if (!_id) {
+            OPENGL_CALL(glGenBuffers(1, &_id));
+        }
+        this->bind();
+        return _id;
+    } 
+    virtual void remove() override {
+        if (_id) {
+            this->unbind();
+            OPENGL_CALL(glDeleteBuffers(1, &_id));
+            _id = 0;
+        }
+    }
+
+    public:
+    const GLenum Target;
+    using OpenGLObject::OpenGLObject;
+    Buffer(GLenum target);
+    Buffer(GLenum target, const ByteVector&, GLenum usage=GL_STATIC_DRAW);
+    Buffer(Buffer&& other);
+    Buffer& operator=(Buffer&& rhs);
+
+    virtual void bind() const override {
+        if (_id) {
+            OPENGL_CALL(glBindBuffer(Target, _id));
+        } else {
+            THROW(OpenGLObjectError(
+                OpenGLObjectError::Codes::INVALID_OBJECT,
+                "w/ BufferType " + BufferTypes[Target]
+            ));
+        }
+    }
+    virtual void unbind() const override { 
+        OPENGL_CALL(glBindBuffer(Target, 0));
+    }
+    GLenum usage() const;
+    size_t size() const;
+    ByteVector data() const;
+
+    void data(const ByteVector& data, GLenum usage=GL_STATIC_DRAW);
+    void data(const void* data, size_t size, GLenum usage=GL_STATIC_DRAW);
+    void subdata(const void* data, size_t size, GLintptr offset=0);
+    void subdata(const ByteVector& data_, GLintptr offset=0);
+    // virtual void clear() const { glClearBufferData(Target, ) }
+
+};
+
+/* template <typename BufferType>
+class ImmutableBuffer : public virtual Buffer {
+    public:
+    ImmutableBuffer() = default;
+    ImmutableBuffer(
+        size_t size_,
+        GLenum usage_ = GL_STATIC_DRAW,
+        GLbitfield flags_=0x0
+    ) : size(size_), Base::usage(usage_) {
+        glBufferStorage(Target, size, nullptr, flags_);
+    }
+
+    std::weak_ptr<void> map(GLbitfield access_) {
+        if (_map && _mapAccess != access_) { unmap(); }
+        _mapAccess = access_;
+        if (!_map) {
+            bind();
+            glMapBuffer(Target, _mapAccess);
+        }
+        return _map;
+    }
+    void unmap() {
+        bind();
+        glUnmapBuffer(Target);
+        _map.reset();
+    }
+    
+    const size_t size;
+
+protected:
+    std::shared_ptr<void> _map = nullptr;
+    GLbitfield _mapAccess = 0;
+
+}; */
+
+class UniformBuffer : public Buffer {
+    protected:
+    GLuint _index;
+
+    public:
+    UniformBuffer();
+    void bind() const override;
+    GLuint bufferIndex() const;
+    GLuint bufferIndex(GLuint);
+
+};
+
+template<typename T>
+struct IsValidGLElementIndexType {
+    static constexpr bool value = false;
+
+};
+
+template<typename T>
+struct ValidGLElementIndexType {
+    static constexpr bool value = true;
+    static constexpr GLenum glsltype = GLSLType<T>::value;
+};
+
+
+template<>
+struct IsValidGLElementIndexType<uint8_t> : public ValidGLElementIndexType<uint8_t> {};
+template<>
+struct IsValidGLElementIndexType<uint16_t> : public ValidGLElementIndexType<uint16_t> {};
+template<>
+struct IsValidGLElementIndexType<uint32_t> : public ValidGLElementIndexType<uint32_t> {};
+
+class ElementBuffer : Buffer {
+    private:
+    template<typename T>
+    inline void checkForElementDataType() {
+        static_assert(IsValidGLElementIndexType<T>::value, 
+            "ElementBuffer data type must resolve to one of GL_UNSIGNED_BYTE,"
+            "GL_UNSIGNED_SHORT, or GL_UNSIGNED_INT"
+        );
+    }
+    
+    protected:
+    using Codes = BufferError::Codes;
+    using OpenGLObject::_id;
+    using Buffer::_usage;
+    using Buffer::_size;
+    using Buffer::declare;
+    using Buffer::remove;
+    GLenum _datatype;
+    template<typename T>
+    inline void checkDatatypeConsistency() {
+        if (_datatype != ValidGLElementIndexType<T>::value) {
+            THROW(BufferError(
+                Codes::BAD_DATA_TYPE,
+                GLenumTable[ValidGLElementIndexType<T>::value] + " not same as buffer "
+                "data type "+GLenumTable[_datatype]
+            ));
+        }
+    }
+
+    public:
+    using Buffer::Target;
+    using Buffer::OpenGLObject;
+    using Buffer::bind;
+    using Buffer::unbind;
+    using Buffer::usage;
+    using Buffer::size;
+    template<typename T>
+    ElementBuffer(const std::vector<T>& indices, GLenum usage=GL_STATIC_DRAW) : Buffer(GL_ELEMENT_ARRAY_BUFFER) {
+        data(indices, usage);
+    }
+
+    inline GLenum datatype() { return _datatype; }
+
+    template<typename T>
+    void data(const std::vector<T>& data, GLenum usage=GL_STATIC_DRAW) {
+        checkForElementDataType<T>();
+        _datatype = ValidGLElementIndexType<T>::glsltype;
+        Buffer::data(vectorToBytes(data), usage);
+    }
+    
+    template<typename T>
+    void data(const T* data, size_t size, GLenum usage=GL_STATIC_DRAW) {
+        checkForElementDataType<T>();
+        _datatype = ValidGLElementIndexType<T>::glsltype;
+        Buffer::data((void*)data, size * sizeof(T), usage);
+    }
+    
+    template<typename T>
+    void subdata(const T* data, size_t size, GLintptr offset=0) {
+        checkForElementDataType<T>();
+        checkDatatypeConsistency<T>();
+        Buffer::subdata((void*)data, size * sizeof(T), offset);
+    }
+    
+    template<typename T>
+    void subdata(const std::vector<T>& data_, GLintptr offset=0) {
+        checkForElementDataType<T>();
+        checkDatatypeConsistency<T>();
+        Buffer::subdata(vectorToBytes(data_), offset);
+    }
+
+};
+
+} // namespace NB
+#endif // _NB_BUFFER