File BufferLayout.h

File List > buffers > BufferLayout.h

Go to the documentation of this file

#pragma once
#include <vector>
#include <GL/glew.h>
#include <type_traits>

struct BufferElement
{
    GLuint type{};
    GLuint count{};
    GLuint is_norm{};

    static GLuint getTypeSize(GLuint type) {
        switch (type)
        {
        case GL_FLOAT:          return 4;
        case GL_UNSIGNED_INT:   return 4;
        case GL_UNSIGNED_BYTE:  return 1;
        }
        return 0;
    }
};


class BufferLayout
{
private:
    std::vector<BufferElement> m_ele_list{};
    GLuint m_stride{};
public:
    BufferLayout()
        :m_stride(0), m_ele_list(0) {};
    ~BufferLayout();

    template<typename T>
    inline constexpr static GLuint ParseType() {
        if constexpr (std::is_same<T, GLfloat>::value) return GL_FLOAT;
        else if      (std::is_same<T, GLuint>::value)  return GL_UNSIGNED_INT;
        else if      (std::is_same<T, GLubyte>::value) return GL_UNSIGNED_BYTE;
        else                                           return GL_NONE;
    }

    template<typename T>
    void Push(GLuint count) {
        //static_assert(false); //add a layout pattern {type, count of element, is_normalized}

        m_ele_list.push_back({ ParseType<T>(), count, GL_FALSE });
        m_stride += sizeof(T) * count; //add up the stride per each Push()
    }

    inline std::vector<BufferElement> GetEles() const { return m_ele_list; };
    inline GLuint GetStride() const { return m_stride; };
};