GLSLProgram.h

#pragma once
 
#include <iostream>
#include <string>
#include "GL/glew.h"
 
#include <vector>
#include <fstream>
 
#include "./Vertex.h"
 
#include "TextureManager/TextureManager.h"
#include "ConsoleLogger.h"
 
#define LINE_OFFSET 2
#define SQUARE_OFFSET 4
 
#define TRIANGLE_VERTICES 3
#define QUAD_INDICES 6
#define BOX_OFFSET 8
 
#define TOTAL_MESHES 4
 
#define TRIANGLE_MESH_IDX 0
#define RECTANGLE_MESH_IDX 1
#define BOX_MESH_IDX 2
#define SPHERE_MESH_IDX 3
 
constexpr int INDICES_LINE_OFFSET = LINE_OFFSET;
constexpr int INDICES_SQUARE_OFFSET = 2 * SQUARE_OFFSET;
constexpr int INDICES_BOX_OFFSET = 3 * BOX_OFFSET;
 
constexpr int ARRAY_BOX_OFFSET = 36;
 
 
static Position triangleVertices[3] = {
    {  0.0f,  0.5f, 0.0f }, // Top
    { -0.5f, -0.5f, 0.0f }, // Bottom Left
    {  0.5f, -0.5f, 0.0f }  // Bottom Right
};
 
static GLuint triangleIndices[3] = {
    0, 1, 2
};
 
static Position quadVertices[4] = {
    {   -0.5f,  0.5f,   0.0f    },
    {   -0.5f,  -0.5f,  0.0f    },
    {   0.5f,   -0.5f,  0.0f    },
    {   0.5f,   0.5f,   0.0f    }
};
 
static UV uv_quadVertices[4] = {
    {0.0f, 0.0f},
    {1.0f, 0.0f},
    {1.0f, 1.0f},
    {0.0f, 1.0f}
};
 
static TextureVertex tex_quadVertices[4] = {
    { glm::vec3(-0.5f,  0.5f, 0.0f),  glm::vec2(0.0f, 1.0f) }, // top-left
    { glm::vec3(-0.5f, -0.5f, 0.0f),  glm::vec2(0.0f, 0.0f) }, // bottom-left
    { glm::vec3(0.5f, -0.5f, 0.0f),  glm::vec2(1.0f, 0.0f) }, // bottom-right
    { glm::vec3(0.5f,  0.5f, 0.0f),  glm::vec2(1.0f, 1.0f) }  // top-right
};
 
static GLuint quadIndices[6] = {
    0, 1, 2,
    2, 3, 0
};
 
static Position cubeVertices[8] = {
    { -0.5f, -0.5f, -0.5f }, 
    {  0.5f, -0.5f, -0.5f }, 
    {  0.5f,  0.5f, -0.5f }, 
    { -0.5f,  0.5f, -0.5f }, 
    { -0.5f, -0.5f,  0.5f }, 
    {  0.5f, -0.5f,  0.5f },
    {  0.5f,  0.5f,  0.5f }, 
    { -0.5f,  0.5f,  0.5f }  
};
 
static LightVertex light_cubeVertices[24] = {
    // Front face
    { glm::vec3(-0.5f, -0.5f, -0.5f), glm::vec3(0.0f, 0.0f, -1.0f) },
    { glm::vec3(0.5f, -0.5f, -0.5f),  glm::vec3(0.0f, 0.0f, -1.0f) },
    { glm::vec3(0.5f, 0.5f, -0.5f),   glm::vec3(0.0f, 0.0f, -1.0f) },
    { glm::vec3(-0.5f, 0.5f, -0.5f),  glm::vec3(0.0f, 0.0f, -1.0f) },
 
    // Back face
    { glm::vec3(-0.5f, -0.5f, 0.5f),  glm::vec3(0.0f, 0.0f, 1.0f) },
    { glm::vec3(0.5f, -0.5f, 0.5f),   glm::vec3(0.0f, 0.0f, 1.0f) },
    { glm::vec3(0.5f, 0.5f, 0.5f),    glm::vec3(0.0f, 0.0f, 1.0f) },
    { glm::vec3(-0.5f, 0.5f, 0.5f),   glm::vec3(0.0f, 0.0f, 1.0f) },
 
    // Left face
    { glm::vec3(-0.5f, -0.5f, -0.5f), glm::vec3(-1.0f, 0.0f, 0.0f) },
    { glm::vec3(-0.5f, -0.5f, 0.5f),  glm::vec3(-1.0f, 0.0f, 0.0f) },
    { glm::vec3(-0.5f, 0.5f, 0.5f),   glm::vec3(-1.0f, 0.0f, 0.0f) },
    { glm::vec3(-0.5f, 0.5f, -0.5f),  glm::vec3(-1.0f, 0.0f, 0.0f) },
 
    // Right face
    { glm::vec3(0.5f, -0.5f, -0.5f),  glm::vec3(1.0f, 0.0f, 0.0f) },
    { glm::vec3(0.5f, -0.5f, 0.5f),   glm::vec3(1.0f, 0.0f, 0.0f) },
    { glm::vec3(0.5f, 0.5f, 0.5f),    glm::vec3(1.0f, 0.0f, 0.0f) },
    { glm::vec3(0.5f, 0.5f, -0.5f),   glm::vec3(1.0f, 0.0f, 0.0f) },
 
    // Bottom face
    { glm::vec3(-0.5f, -0.5f, -0.5f), glm::vec3(0.0f, -1.0f, 0.0f) },
    { glm::vec3(0.5f, -0.5f, -0.5f),  glm::vec3(0.0f, -1.0f, 0.0f) },
    { glm::vec3(0.5f, -0.5f, 0.5f),   glm::vec3(0.0f, -1.0f, 0.0f) },
    { glm::vec3(-0.5f, -0.5f, 0.5f),  glm::vec3(0.0f, -1.0f, 0.0f) },
 
    // Top face
    { glm::vec3(-0.5f, 0.5f, -0.5f),  glm::vec3(0.0f, 1.0f, 0.0f) },
    { glm::vec3(0.5f, 0.5f, -0.5f),   glm::vec3(0.0f, 1.0f, 0.0f) },
    { glm::vec3(0.5f, 0.5f, 0.5f),    glm::vec3(0.0f, 1.0f, 0.0f) },
    { glm::vec3(-0.5f, 0.5f, 0.5f),   glm::vec3(0.0f, 1.0f, 0.0f) }
};
 
static GLuint cubeIndices[36] = {
     0, 1, 2,
    2, 3, 0,
 
    // Back face (vertices 4-7)
    4, 5, 6,
    6, 7, 4,
 
    // Left face (vertices 8-11)
    8, 9,10,
    10,11,8,
 
    // Right face (vertices 12-15)
    12,13,14,
    14,15,12,
 
    // Bottom face (vertices 16-19)
    16,17,18,
    18,19,16,
 
    // Top face (vertices 20-23)
    20,21,22,
    22,23,20
};
 
 
static void generateSphereMesh(std::vector<Position>& vertices, std::vector<GLuint>& indices,
    float radius = 1.0f, unsigned int sectorCount = 36, unsigned int stackCount = 18) {
    const float PI = 3.14159265359f;
 
    vertices.clear();
    indices.clear();
 
    for (unsigned int i = 0; i <= stackCount; ++i) {
        float stackAngle = PI / 2.0f - i * PI / stackCount;  // from pi/2 to -pi/2
        float xy = radius * cosf(stackAngle);
        float z = radius * sinf(stackAngle);
 
        for (unsigned int j = 0; j <= sectorCount; ++j) {
            float sectorAngle = j * 2.0f * PI / sectorCount;
 
            float x = xy * cosf(sectorAngle);
            float y = xy * sinf(sectorAngle);
            glm::vec3 pos(x, y, z);
 
            vertices.push_back(pos);
        }
    }
 
    for (unsigned int i = 0; i < stackCount; ++i) {
        unsigned int k1 = i * (sectorCount + 1);
        unsigned int k2 = k1 + sectorCount + 1;
 
        for (unsigned int j = 0; j < sectorCount; ++j, ++k1, ++k2) {
            if (i != 0) {
                indices.push_back(k1);
                indices.push_back(k2);
                indices.push_back(k1 + 1);
            }
            if (i != (stackCount - 1)) {
                indices.push_back(k1 + 1);
                indices.push_back(k2);
                indices.push_back(k2 + 1);
            }
        }
    }
}
 
static void generateSphereMesh(std::vector<LightVertex>& vertices, std::vector<GLuint>& indices,
    float radius = 1.0f, unsigned int sectorCount = 36, unsigned int stackCount = 18) {
    const float PI = 3.14159265359f;
 
    vertices.clear();
    indices.clear();
 
    for (unsigned int i = 0; i <= stackCount; ++i) {
        float stackAngle = PI / 2.0f - i * PI / stackCount;  // from pi/2 to -pi/2
        float xy = radius * cosf(stackAngle);
        float z = radius * sinf(stackAngle);
 
        for (unsigned int j = 0; j <= sectorCount; ++j) {
            float sectorAngle = j * 2.0f * PI / sectorCount;
 
            float x = xy * cosf(sectorAngle);
            float y = xy * sinf(sectorAngle);
            glm::vec3 pos(x, y, z);
 
            glm::vec3 normal = glm::normalize(pos);
            vertices.push_back({ pos, normal });
        }
    }
 
    for (unsigned int i = 0; i < stackCount; ++i) {
        unsigned int k1 = i * (sectorCount + 1);
        unsigned int k2 = k1 + sectorCount + 1;
 
        for (unsigned int j = 0; j < sectorCount; ++j, ++k1, ++k2) {
            if (i != 0) {
                indices.push_back(k1);
                indices.push_back(k2);
                indices.push_back(k1 + 1);
            }
            if (i != (stackCount - 1)) {
                indices.push_back(k1 + 1);
                indices.push_back(k2);
                indices.push_back(k2 + 1);
            }
        }
    }
}
 
struct InstanceData {
 
    InstanceData() {}
    InstanceData(glm::vec3 mSize, Position mBodyCenter, Rotation mRotation) :
        size(mSize),
        bodyCenter(mBodyCenter),
        rotation(mRotation)
    {
    }
 
    InstanceData(glm::vec2 mSize, Position mBodyCenter, Rotation mRotation) :
        size(glm::vec3(mSize, 0.0f)),
        bodyCenter(mBodyCenter),
        rotation(mRotation)
    {
    }
 
    ~InstanceData() {}
 
    Size size = glm::vec3(0.0f);
    Position bodyCenter = glm::vec3(0.0f);
    Rotation rotation = glm::vec3(0.0f);
};
 
 
struct ColorInstanceData : InstanceData {
 
    ColorInstanceData() {}
    ColorInstanceData(glm::vec3 mSize, Position mBodyCenter, Rotation mRotation, Color mColor) : InstanceData(mSize, mBodyCenter, mRotation), color(mColor) {
    }
    ColorInstanceData(glm::vec2 mSize, Position mBodyCenter, Rotation mRotation, Color mColor) : InstanceData(mSize, mBodyCenter, mRotation), color(mColor) {
    }
 
    ~ColorInstanceData() {};
 
    Color color = Color(255, 255, 255, 255);
};
 
struct TextureInstanceData : InstanceData {
 
    TextureInstanceData() {}
    TextureInstanceData(glm::vec3 mSize, Position mBodyCenter, Rotation mRotation, GLuint Texture) : InstanceData(mSize, mBodyCenter, mRotation), texture(Texture) {
    }
    TextureInstanceData(glm::vec2 mSize, Position mBodyCenter, Rotation mRotation, GLuint Texture) : InstanceData(mSize, mBodyCenter, mRotation), texture(Texture) {
    }
 
    ~TextureInstanceData() {};
 
    GLuint texture = 0;
    UV uv = glm::vec2(0.0f);
};
 
struct BaseRenderer {
    size_t meshIndices = 0;
    
    GLuint vao;
 
    //for static draws
    GLuint vbo; 
    GLuint ibo;
};
 
struct MeshRenderer : BaseRenderer {
    std::vector<InstanceData> instances;
};
 
struct ColorMeshRenderer : BaseRenderer {
    std::vector<ColorInstanceData> instances;
};
 
struct TextureMeshRenderer : BaseRenderer {
    std::vector<TextureInstanceData> instances;
};
 
class GLSLProgram {
public:
    GLSLProgram() : _programID(0), _vertexShaderID(0), _geometryShaderID(0), _fragmentShaderID(0), _numAttributes(0)
    {
 
    }
 
    ~GLSLProgram() {
 
    }
 
    // Vertex + Fragment
    void compileAndLinkShaders(const std::string& vertexShaderFilePath, const std::string& fragmentShaderFilePath) {
        std::string vertSource = readShaderFile(vertexShaderFilePath);
        std::string fragSource = readShaderFile(fragmentShaderFilePath);
 
        compileAndLinkShadersFromSource(vertSource.c_str(), fragSource.c_str());
    }
 
    // Vertex + Geometry + Fragment
    void compileAndLinkShaders(const std::string& vertexShaderFilePath, const std::string& geometryShaderFilePath, const std::string& fragmentShaderFilePath) {
        std::string vertSource = readShaderFile(vertexShaderFilePath);
        std::string geomSource = readShaderFile(geometryShaderFilePath);
        std::string fragSource = readShaderFile(fragmentShaderFilePath);
 
        compileAndLinkShadersFromSource(vertSource.c_str(), geomSource.c_str(), fragSource.c_str());
    }
 
    void compileAndLinkShadersFromSource(const char* vertexSource, const char* fragmentSource) {
 
        std::vector<GLuint> shaderIDs;
 
        shaderIDs.push_back(createAndCompileShader(vertexSource, GL_VERTEX_SHADER, "Vertex"));
        shaderIDs.push_back(createAndCompileShader(fragmentSource, GL_FRAGMENT_SHADER, "Fragment"));
 
        linkShadersInternal(shaderIDs);
    }
 
    void compileAndLinkShadersFromSource(const char* vertexSource, const char* geometrySource, const char* fragmentSource) {
 
        std::vector<GLuint> shaderIDs;
 
        shaderIDs.push_back(createAndCompileShader(vertexSource, GL_VERTEX_SHADER, "Vertex"));
        shaderIDs.push_back(createAndCompileShader(geometrySource, GL_GEOMETRY_SHADER, "Geometry"));
        shaderIDs.push_back(createAndCompileShader(fragmentSource, GL_FRAGMENT_SHADER, "Fragment"));
 
        linkShadersInternal(shaderIDs);
    }
 
 
    void addAttribute(const std::string& attributeName) {
        glBindAttribLocation(_programID, _numAttributes++, attributeName.c_str());
    }
 
    GLint getUniformLocation(const std::string& uniformName) {
        GLint location = glGetUniformLocation(_programID, uniformName.c_str());
 
        if (location == GL_INVALID_INDEX) {
            TazGraphEngine::ConsoleLogger::error("Uniform " + uniformName + " not found in shader!");
        }
        return location;
    }
 
    void use() {
        glUseProgram(_programID);
        for (int i = 0; i < _numAttributes; i++) {
            glEnableVertexAttribArray(i);
        }
    }
 
    void unuse() {
        glUseProgram(0);
        for (int i = 0; i < _numAttributes; i++) {
            glDisableVertexAttribArray(i);
        }
    }
 
    void dispose() {
        if(_programID != 0) glDeleteProgram(_programID);
    }
 
    GLuint getProgramID() {
        return _programID;
    }
 
private:
    GLuint _programID;
 
    GLuint _vertexShaderID;
    GLuint _geometryShaderID;
    GLuint _fragmentShaderID;
 
    int _numAttributes;
 
    std::string readShaderFile(const std::string& filePath) {
        std::vector<unsigned char> buffer;
        TextureManager::readFileToBuffer(filePath.c_str(), buffer);
        return std::string(buffer.begin(), buffer.end());
    }
 
    GLuint createAndCompileShader(const std::string& source, GLenum shaderType, const std::string& typeName) {
        GLuint shaderID = glCreateShader(shaderType);
        if (shaderID == 0) {
            TazGraphEngine::ConsoleLogger::error(typeName + " Shader Failed to create!");
            return 0;
        }
 
        compileShader(source.c_str(), typeName, shaderID);
        return shaderID;
    }
 
    void compileShader(const char* source, const std::string& name, GLuint id) {
 
        glShaderSource(id, 1, &source, nullptr); //1 for number of strings
 
        glCompileShader(id);
 
        GLint success = 0;
        glGetShaderiv(id, GL_COMPILE_STATUS, &success);
 
        if (success == GL_FALSE)
        {
            GLint maxLength = 0;
            glGetShaderiv(id, GL_INFO_LOG_LENGTH, &maxLength);
 
            // The maxLength includes the NULL character
            std::vector<GLchar> errorLog(maxLength);
            glGetShaderInfoLog(id, maxLength, &maxLength, &errorLog[0]);
 
            // Provide the infolog in whatever manor you deem best.
            // Exit with failure.
            glDeleteShader(id); // Don't leak the shader.
 
            std::printf("%s\n", &(errorLog[0]));
            std::cout << "Shader " + name + " failed to compile" << std::endl;
 
        }
    }
 
    void linkShadersInternal(const std::vector<GLuint>& shaderIDs) {
        _programID = glCreateProgram();
 
        // Attach all shaders
        for (GLuint shaderID : shaderIDs) {
            glAttachShader(_programID, shaderID);
        }
 
        // Link program
        glLinkProgram(_programID);
 
        // Check link status
        GLint isLinked = 0;
        glGetProgramiv(_programID, GL_LINK_STATUS, &isLinked);
 
        if (isLinked == GL_FALSE) {
            GLint maxLength = 0;
            glGetProgramiv(_programID, GL_INFO_LOG_LENGTH, &maxLength);
 
            std::vector<GLchar> errorLog(maxLength);
            glGetProgramInfoLog(_programID, maxLength, &maxLength, &errorLog[0]);
 
            // Cleanup on failure
            glDeleteProgram(_programID);
            for (GLuint shaderID : shaderIDs) {
                glDeleteShader(shaderID);
            }
 
            std::printf("%s\n", &errorLog[0]);
            TazGraphEngine::ConsoleLogger::error("Shaders failed to link");
            return;
        }
 
        // Cleanup shaders after successful link
        for (GLuint shaderID : shaderIDs) {
            glDetachShader(_programID, shaderID);
            glDeleteShader(shaderID);
        }
    }
 
};