Shader.cpp

#include <Shader.h>
#include <fstream>
#include <sstream>
#include <iostream>

using namespace std;

// --- Load GLSL source from file ----
string Shader::loadFile(const string& path)
{
    ifstream file(path);

    if (!file.is_open())
    {
        cerr << "[Shader] Cannotopen: " << path << endl;
        return "";
    }
    stringstream buf;
    buf << file.rdbuf();
    return buf.str();
}

// --- Compile one shader stage ---
GLuint Shader::compile(const string& src, GLenum type)
{
    const char* c = src.c_str();
    GLuint id = glCreateShader(type);
    glShaderSource(id, 1, &c, NULL);
    glCompileShader(id);

    int ok;
    glGetShaderiv(id, GL_COMPILE_STATUS, &ok);

    if (!ok){
        char log[1024];
        glGetShaderInfoLog(id, 1024, NULL, log);
        cerr << "[Shader] Compile error (" 
        << (type == GL_VERTEX_SHADER ? "VERT" : "FRAG")
        << "):\n" << log << endl;
    }
    return id;
}

// ------ Constructor: compile + link ------
Shader::Shader(const string& vertPath, const string& fragPath)
{
    GLuint vert = compile(loadFile(vertPath), GL_VERTEX_SHADER);
    GLuint frag = compile(loadFile(fragPath), GL_FRAGMENT_SHADER);

    ID = glCreateProgram();
    glAttachShader(ID, vert);
    glAttachShader(ID, frag);
    glLinkProgram(ID);

    int ok;
    glGetProgramiv(ID, GL_LINK_STATUS, &ok);

    if (!ok)
    {
        char log[1024];
        glGetProgramInfoLog(ID, 1024, NULL, log);
        cerr << "[Shader] Link error:\n" << log << endl;
    }

    glDeleteShader(vert);
    glDeleteShader(frag);
}

void Shader::use()           { glUseProgram(ID); }
GLuint Shader::getID() const { return ID; }

void Shader::setInt(const string& name, int v){
    glUniform1i(glGetUniformLocation(ID, name.c_str()), v);
}

void Shader::setFloat(const string& name, float v){
    glUniform1f(glGetUniformLocation(ID, name.c_str()), v);
}

void Shader::setBool(const string& name, bool v){
    glUniform1i(glGetUniformLocation(ID, name.c_str()), (int)v);
}

void Shader::setVec2(const string& name, float x, float y) {
    glUniform2f(glGetUniformLocation(ID, name.c_str()), x, y);
}

void Shader::setVec3(const string& name, float x, float y, float z){
    glUniform3f(glGetUniformLocation(ID, name.c_str()), x, y, z);
}

void Shader::setMat4(const string& name, const float* v){
    glUniformMatrix4fv(glGetUniformLocation(ID, name.c_str()), 1, GL_FALSE, v);
}