Abstraction

Blue/src/IndexBuffer.cpp

@@ -16,12 +16,12 @@ IndexBuffer::~IndexBuffer()
     glDeleteBuffers(1, &m_RendererID);
 }
 
-void IndexBuffer::Bind()
+void IndexBuffer::Bind() const
 {
     glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, m_RendererID);
 }
 
-void IndexBuffer::Unbind()
+void IndexBuffer::Unbind() const
 {
     glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
 }

Blue/src/IndexBuffer.h

@@ -12,8 +12,8 @@ class IndexBuffer
     IndexBuffer(const unsigned *data, unsigned int count);
     ~IndexBuffer();
 
-    void Bind();
-    void Unbind();
+    void Bind() const;
+    void Unbind() const;
 
     inline unsigned int GetCount() const { return m_Count; }
 };

Blue/src/Renderer.cpp

@@ -1 +1,13 @@
-#include "Renderer.h"
+#include "Renderer.h"
+
+void Renderer::Clear() const
+{
+    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+}
+void Renderer::Draw(const VertexArray &va, const IndexBuffer &ib, const Shader &shader) const
+{
+    shader.Bind();
+    va.Bind();
+    ib.Bind();
+    glDrawElements(GL_TRIANGLES, ib.GetCount(), GL_UNSIGNED_INT, nullptr);
+}

Blue/src/Renderer.h

@@ -1,4 +1,16 @@
 #pragma once
 
 #include "GL/glew.h"
-#include "GLFW/glfw3.h"
+#include "GLFW/glfw3.h"
+#include "VertexArray.h"
+#include "IndexBuffer.h"
+#include "Shader.h"
+
+class Renderer
+{
+
+private:
+public:
+    void Clear() const;
+    void Draw(const VertexArray &va, const IndexBuffer &ib, const Shader &shader) const;
+};

Blue/src/Shader.cpp

@@ -0,0 +1,111 @@
+#include "Shader.h"
+#include <iostream>
+#include <string.h>
+#include <fstream>
+#include <sstream>
+
+Shader::Shader(const std::string &filepath)
+    : m_FilePath(filepath), m_RendererID(0)
+{
+    struct ShaderProgramSource shaderSource = ParseShader(filepath);
+    m_RendererID = CreateShader(shaderSource.VertexSource, shaderSource.FragmentSource);
+}
+
+Shader::~Shader()
+{
+    glDeleteProgram(m_RendererID);
+}
+
+struct ShaderProgramSource Shader::ParseShader(std::string filePath)
+{
+    enum class ShaderType
+    {
+        NONE = -1,
+        VERTEX = 0,
+        FRAGMENT = 1
+    };
+    std::ifstream stream(filePath);
+    std::string line;
+    std::stringstream ss[2];
+    ShaderType type = ShaderType::NONE;
+
+    while (getline(stream, line))
+    {
+        if (line.find("#shader") != std::string::npos)
+        {
+            if (line.find("vertex") != std::string::npos)
+                type = ShaderType::VERTEX;
+            else if (line.find("fragment") != std::string::npos)
+                type = ShaderType::FRAGMENT;
+        }
+        else
+            ss[(int)type] << line << "\n";
+    }
+    return {ss[0].str(), ss[1].str()};
+}
+
+unsigned int Shader::CreateShader(const std::string vertexShader, const std::string fragmentShader)
+{
+    unsigned int program = glCreateProgram();
+
+    unsigned int vs = CompileShader(GL_VERTEX_SHADER, vertexShader);
+    unsigned int fs = CompileShader(GL_FRAGMENT_SHADER, fragmentShader);
+
+    glAttachShader(program, fs);
+    glAttachShader(program, vs);
+    glLinkProgram(program);
+
+    return program;
+}
+
+unsigned int Shader::CompileShader(unsigned int type, const std::string &source)
+{
+    unsigned int id = glCreateShader(type);
+    const char *src = source.c_str();
+    glShaderSource(id, 1, &src, NULL);
+    glCompileShader(id);
+
+    int result;
+    glGetShaderiv(id, GL_COMPILE_STATUS, &result);
+    if (result == GL_FALSE)
+    {
+        int length;
+        glGetShaderiv(id, GL_INFO_LOG_LENGTH, &length);
+        char message[length];
+        glGetShaderInfoLog(id, length, &length, message);
+        std::cout << "Failed to compile " << (type == GL_VERTEX_SHADER ? "vertex" : "fragment") << "shader" << std::endl;
+        std::cout << message << std::endl;
+        glDeleteShader(id);
+        return 0;
+    }
+
+    return id;
+}
+
+void Shader::Bind() const
+{
+    glUseProgram(m_RendererID);
+}
+
+void Shader::Unbind() const
+{
+    glUseProgram(0);
+}
+
+void Shader::SetUniform4f(const std::string &name, float v0, float v1, float v2, float v3)
+{
+    glUniform4f(GetUniformLocation(name), v0, v1, v2, v3);
+}
+
+int Shader::GetUniformLocation(const std::string &name)
+{
+    if (m_UniformLocationCache.find(name) != m_UniformLocationCache.end())
+        return m_UniformLocationCache[name];
+
+    int location = glGetUniformLocation(m_RendererID, name.c_str());
+    if (location == -1)
+        std::cout << "Warning: Uniform " << name << " doesn't exist !" << std::endl;
+    else
+        m_UniformLocationCache[name] = location;
+    return location;
+}

Blue/src/Shader.h

@@ -0,0 +1,34 @@
+#pragma once
+#include <string>
+#include "GL/glew.h"
+#include "GLFW/glfw3.h"
+#include <unordered_map>
+
+struct ShaderProgramSource
+{
+    std::string VertexSource;
+    std::string FragmentSource;
+};
+
+class Shader
+{
+private:
+    unsigned int m_RendererID;
+    std::string m_FilePath;
+    std::unordered_map<std::string, int> m_UniformLocationCache;
+
+public:
+    Shader(const std::string &filepath);
+    ~Shader();
+
+    void Bind() const;
+    void Unbind() const;
+
+    void SetUniform4f(const std::string &name, float v0, float v1, float v2, float v3);
+
+private:
+    unsigned int CompileShader(unsigned int type, const std::string &source);
+    int GetUniformLocation(const std::string &name);
+    unsigned int CreateShader(const std::string vertexShader, const std::string fragmentShader);
+    struct ShaderProgramSource ParseShader(std::string filePath);
+};

Blue/src/VertexArray.h

@@ -14,5 +14,5 @@ class VertexArray
 
     void AddBuffer(const VertexBuffer &vb, const VertexBufferLayout &layout);
     void Bind() const;
-    void UnBind() const;
+    void Unbind() const;
 };

Blue/src/VertexBufferLayout.cpp

@@ -3,20 +3,20 @@
 template <>
 void VertexBufferLayout::Push<float>(unsigned int count)
 {
-    m_Elements.push_back({count, GL_FLOAT, GL_FALSE});
+    m_Elements.push_back({GL_FLOAT, count, GL_FALSE});
     m_Stride += sizeof(GLfloat) * count;
 }
 
 template <>
 void VertexBufferLayout::Push<unsigned int>(unsigned int count)
 {
-    m_Elements.push_back({count, GL_UNSIGNED_INT, GL_FALSE});
+    m_Elements.push_back({GL_UNSIGNED_INT, count, GL_FALSE});
     m_Stride += sizeof(GLuint) * count;
 }
 
 template <>
 void VertexBufferLayout::Push<unsigned char>(unsigned int count)
 {
-    m_Elements.push_back({count, GL_UNSIGNED_BYTE, GL_TRUE});
+    m_Elements.push_back({GL_UNSIGNED_BYTE, count, GL_TRUE});
     m_Stride += sizeof(GLbyte) * count;
 }

src/IndexBuffer.h

@@ -24,11 +24,11 @@ class IndexBuffer
         glDeleteBuffers(1, &m_RendererID);
     }
 
-    void Bind()
+    void Bind() const
     {
         glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, m_RendererID);
     }
-    void Unbind()
+    void Unbind() const
     {
         glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
     }

src/Renderer.h

@@ -1,4 +1,29 @@
 #pragma once
 
 #include "GL/glew.h"
-#include "GLFW/glfw3.h"
+#include "GLFW/glfw3.h"
+#include "VertexArray.h"
+#include "IndexBuffer.h"
+#include "Shader.h"
+
+class Renderer
+{
+
+private:
+public:
+    void Clear() const;
+    void Draw(const VertexArray &va, const IndexBuffer &ib, const Shader &shader) const;
+};
+
+void Renderer::Draw(const VertexArray &va, const IndexBuffer &ib, const Shader &shader) const
+{
+    shader.Bind();
+    va.Bind();
+    ib.Bind();
+    glDrawElements(GL_TRIANGLES, ib.GetCount(), GL_UNSIGNED_INT, nullptr);
+}
+
+void Renderer::Clear() const
+{
+    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+}