ShaderLoader.cpp

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#include "ShaderLoader.h"

using namespace std;

ShaderLoader::ShaderLoader(void)
{
}


ShaderLoader::~ShaderLoader(void)
{
}

GLuint ShaderLoader::LoadShaders(const char * vertex_path, const char * fragment_path, const char * geo_path)
{
    // set up the handle to the individual shaders
    GLuint Vertexhandle = glCreateShader(GL_VERTEX_SHADER);
    GLuint Fragmenthandle = glCreateShader(GL_FRAGMENT_SHADER);
    GLuint Geometryhandle = glCreateShader(GL_GEOMETRY_SHADER);

    // -.-.-.-.- shader Programme laden -.-.-.-.-.-.-
    //load vertex shader
    string VertexShaderCode;
    ifstream VertexShaderStream(vertex_path, ios::in);
    if(VertexShaderStream.is_open())
    {
        string Line = "";
        while(getline(VertexShaderStream, Line))
            VertexShaderCode += "\n" + Line;
        VertexShaderStream.close();
    }
    
    //load fragment shader
    string FragmentShaderCode;
    ifstream FragmentShaderStream(fragment_path, ios::in);
    if(FragmentShaderStream.is_open())
    {
        string Line = "";
        while(getline(FragmentShaderStream, Line))
            FragmentShaderCode += "\n" + Line;
        FragmentShaderStream.close();
    }

    //load geometry shader
    string GeometryShaderCode;
    ifstream GeometryShaderStream(geo_path, ios::in);
    if(GeometryShaderStream.is_open())
    {
        string Line = "";
        while(getline(GeometryShaderStream, Line))
            GeometryShaderCode += "\n" + Line;
        GeometryShaderStream.close();
    }
    // -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-

    // -.-.-.-.- vertex Shader Compilieren -.-.-.-.-.-.- 
    //compile vertex shader
    char const * VertexPtr = VertexShaderCode.c_str();
    glShaderSource(Vertexhandle, 1, &VertexPtr , NULL);
    glCompileShader(Vertexhandle);

    // test ob erfolgreich
    //test vertex shader
    GLint succeded;
    glGetShaderiv(Vertexhandle, GL_COMPILE_STATUS, &succeded);
    if (succeded == GL_FALSE)
    {
        //Log auslesen und ausgeben
        GLint logSize;
        glGetShaderiv(Vertexhandle, GL_INFO_LOG_LENGTH, &logSize);
        GLchar* message = new char[logSize];
        glGetShaderInfoLog(Vertexhandle, logSize, NULL, message);
        delete[] message;
    }
    // -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-

    // -.-.-.-.- fragment Shader Compilieren -.-.-.-.-.-.- 
    //compile fragment shader
    char const * FragmentPtr = FragmentShaderCode.c_str();
    glShaderSource(Fragmenthandle, 1, &FragmentPtr , NULL);
    glCompileShader(Fragmenthandle);

    // test ob erfolgreich
    //test fragment shader
    glGetShaderiv(Fragmenthandle, GL_COMPILE_STATUS, &succeded);
    if (succeded == GL_FALSE)
    {
        //Log auslesen und ausgeben
        GLint logSize;
        glGetShaderiv(Fragmenthandle, GL_INFO_LOG_LENGTH, &logSize);
        GLchar* message = new char[logSize];
        glGetShaderInfoLog(Fragmenthandle, logSize, NULL, message);
        delete[] message;
    }
    // -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-

    // -.-.-.-.- geometry Shader Compilieren -.-.-.-.-.-.- 
    //compile geometry shader
    char const * GeometryPtr = GeometryShaderCode.c_str();
    glShaderSource(Geometryhandle, 1, &GeometryPtr , NULL);
    glCompileShader(Geometryhandle);

    // test ob erfolgreich
    //test geometry shader
    glGetShaderiv(Geometryhandle, GL_COMPILE_STATUS, &succeded);
    if (succeded == GL_FALSE)
    {
        //Log auslesen und ausgeben
        GLint logSize;
        glGetShaderiv(Geometryhandle, GL_INFO_LOG_LENGTH, &logSize);
        GLchar* message = new char[logSize];
        glGetShaderInfoLog(Geometryhandle, logSize, NULL, message);
        delete[] message;
    }
    // -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-

    // -.-.-.-.- Shader Linken -.-.-.-.-.-.- 
    //link the shaders to a program
    GLuint programHandle = glCreateProgram();
    glAttachShader(programHandle, Vertexhandle);
    glAttachShader(programHandle, Fragmenthandle);
    //glAttachShader(programHandle, Geometryhandle); //geometry shader not used in this project version

    glBindFragDataLocation(programHandle, 0, "fragColor"); //Output "fragColor" auf position 0 legen
    glLinkProgram(programHandle);
    // -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-

    // -.-.-.-.- testen ob programm richtig angelegt -.-.-.-.-.-.- 
    //test program
    glGetProgramiv(programHandle, GL_LINK_STATUS, &succeded);
    if (!succeded)
    {
        //Log auslesen und ausgeben
        GLint logSize;
        glGetShaderiv(programHandle, GL_INFO_LOG_LENGTH, &logSize);
        GLchar* message = new char[logSize];
        glGetShaderInfoLog(programHandle, logSize, NULL, message);
        delete[] message;
    }
    // -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-

    glDeleteShader(Vertexhandle);
    glDeleteShader(Fragmenthandle);
    glDeleteShader(Geometryhandle);

    return programHandle;
}