Shader.cpp

#include <iostream>
#include <vector>
#include <fstream>
#include <algorithm>
#include <sstream>

#include <Shader.h>

using namespace std;

GLuint sen::LoadShaders(const std::string &vertex_file_path, const std::string &fragment_file_path)
{
	GLuint VertexShaderID = glCreateShader(GL_VERTEX_SHADER);
	GLuint FragmentShaderID = glCreateShader(GL_FRAGMENT_SHADER);

	std::string VertexShaderCode;
	std::ifstream VertexShaderStream(vertex_file_path, std::ios::in);
	if (VertexShaderStream.is_open())
	{
		std::stringstream sstr;
		sstr << VertexShaderStream.rdbuf();
		VertexShaderCode = sstr.str();
		VertexShaderStream.close();
	}
	else
	{
		std::cout << "Impossible to open " << vertex_file_path << ". Are you in the right directory ? Don't forget to read the FAQ !" << std::endl;
		return 0;
	}

	std::string FragmentShaderCode;
	std::ifstream FragmentShaderStream(fragment_file_path, std::ios::in);
	if (FragmentShaderStream.is_open())
	{
		std::stringstream sstr;
		sstr << FragmentShaderStream.rdbuf();
		FragmentShaderCode = sstr.str();
		FragmentShaderStream.close();
	}

	GLint Result = GL_FALSE;
	int InfoLogLength;

	std::cout << "Compiling shader: " << vertex_file_path << std::endl;
	char const * VertexSourcePointer = VertexShaderCode.c_str();
	glShaderSource(VertexShaderID, 1, &VertexSourcePointer, NULL);
	glCompileShader(VertexShaderID);

	glGetShaderiv(VertexShaderID, GL_COMPILE_STATUS, &Result);
	glGetShaderiv(VertexShaderID, GL_INFO_LOG_LENGTH, &InfoLogLength);
	if (InfoLogLength > 0)
	{
		std::vector<char> VertexShaderErrorMessage(InfoLogLength + 1);
		glGetShaderInfoLog(VertexShaderID, InfoLogLength, NULL, &VertexShaderErrorMessage[0]);
		std::cout << &VertexShaderErrorMessage[0] << std::endl;
	}

	std::cout << "Compiling shader: " << fragment_file_path << std::endl;
	char const * FragmentSourcePointer = FragmentShaderCode.c_str();
	glShaderSource(FragmentShaderID, 1, &FragmentSourcePointer, NULL);
	glCompileShader(FragmentShaderID);

	glGetShaderiv(FragmentShaderID, GL_COMPILE_STATUS, &Result);
	glGetShaderiv(FragmentShaderID, GL_INFO_LOG_LENGTH, &InfoLogLength);
	if (InfoLogLength > 0)
	{
		std::vector<char> FragmentShaderErrorMessage(InfoLogLength + 1);
		glGetShaderInfoLog(FragmentShaderID, InfoLogLength, NULL, &FragmentShaderErrorMessage[0]);
		std::cout << &FragmentShaderErrorMessage[0] << std::endl;
	}

	std::cout << "Linking program" << std::endl;
	GLuint ProgramID = glCreateProgram();
	glAttachShader(ProgramID, VertexShaderID);
	glAttachShader(ProgramID, FragmentShaderID);
	glLinkProgram(ProgramID);

	glGetProgramiv(ProgramID, GL_LINK_STATUS, &Result);
	glGetProgramiv(ProgramID, GL_INFO_LOG_LENGTH, &InfoLogLength);
	if (InfoLogLength > 0)
	{
		std::vector<char> ProgramErrorMessage(InfoLogLength + 1);
		glGetProgramInfoLog(ProgramID, InfoLogLength, NULL, &ProgramErrorMessage[0]);
		std::cout << &ProgramErrorMessage[0] << std::endl;
	}

	glDetachShader(ProgramID, VertexShaderID);
	glDetachShader(ProgramID, FragmentShaderID);

	glDeleteShader(VertexShaderID);
	glDeleteShader(FragmentShaderID);

	return ProgramID;
}