Assertion error when trying to include textures SDL2 c++ - c++

Question

I made a graphic engine with SDL2, and when I add a texture, it displays an error:
However, if i dont include textures, everything works fine.
I also have reasons to belive, that the error is connected to the IDE, because I read other questions.
My IDE: VS 2017 pro
The code
run()
void maingame::run()
{
initSystems();
_sprite.init(-1.0f, -1.0f, 2.0f, 2.0f);
_enemyTexture = ImageLoader::loadPNG("textures/jimmyJump_pack/PNG/CharacterRight_Standing.png");
gameLoop();
}
run() method gets called by main() func
The initialization of the sprite:
void targetSprite::init(float x, float y, float width, float height)
{
_x = x;
_y = y;
_width = width;
_height = height;
if (_vboID == 0) {
glGenBuffers(1, &_vboID);
}
Vertex vertexData[6];
//1st
vertexData[0].setPos(_x + _width, _y + _height);
vertexData[0].setUV(1.0f, 1.0f);
vertexData[1].setPos(_x, _y + _height);
vertexData[1].setUV(0.0f, 1.0f);
vertexData[2].setPos(_x, _y);
vertexData[2].setUV(0.0f, 0.0f);
//2nd
vertexData[3].setPos(_x, _y);
vertexData[3].setUV(0.0f, 0.0f);
vertexData[4].setPos(_x + _width, _y);
vertexData[4].setUV(1.0f, 0.0f);
vertexData[5].setPos(_x + _width, _y + _height);
vertexData[5].setUV(1.0f, 1.0f);
for (int i = 0; i < 6; i++) {
vertexData[i].setColor(127, 127, 255, 255);
}
vertexData[1].setColor(255, 0, 255, 255);
vertexData[4].setColor(0, 255, 255, 255);
glBindBuffer(GL_ARRAY_BUFFER, _vboID);
glBufferData(GL_ARRAY_BUFFER, sizeof(vertexData), vertexData, GL_STATIC_DRAW);
glBindBuffer(GL_ARRAY_BUFFER, _vboID);
}
I posted this because I belive the error is in here.
But it is not necessary, because this same code runs whitout textures.
On line 10 "Vertex" is a struct.
I tried changing build from debug to release, but then I got problems with .dll files.
EDIT:
This calls the error in vector:
GLTexture ImageLoader::loadPNG(std::string filePath)
{
GLTexture texture = {};
std::vector<unsigned char> out;
unsigned long width;
unsigned long height;
std::vector<unsigned char> in;
if (IOManager::readFileToBuffer(filePath, in) == false) { //read the texture to buffer
fatalError2("FTB 1");
}
int errorCode = decodePNG(out, width, height, &(in[0]), in.size()); //error line
if (errorCode != 0) {
fatalError2("DPNG 1: " + std::to_string(errorCode));
}
glGenTextures(1, &(texture.id));
glBindTexture(GL_TEXTURE_2D, texture.id);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, &(out[0]));
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
glGenerateMipmap(GL_TEXTURE_2D);
glBindTexture(GL_TEXTURE_2D, 0);
texture.width = width;
texture.height = height;
return texture;
}
Line 25, then goes back to run(), main(), and then opens a "sdl_windows_main.c not found" window.
So i guess the question is where that file is located?
EDIT 2
the readFileToBuffer() method, i belive responsible for filling the "in" vector
bool IOManager::readFileToBuffer(std::string filePath, std::vector<unsigned char> buffer)
{
std::ifstream file(filePath, std::ios::binary);
if (file.fail()) {
perror(filePath.c_str());
return false;
}
file.seekg(0, std::ios::end);
int fileSize = file.tellg();
file.seekg(0, std::ios::beg);
fileSize = fileSize - file.tellg();
buffer.resize(fileSize);
file.read((char *)&(buffer[0]), fileSize);
file.close();
return true;
}

Answer 1

The solution was to pass "buffer" by reference
bool IOManager::readFileToBuffer(std::string filePath, std::vector<unsigned char>&buffer)
{
std::ifstream file(filePath, std::ios::binary);
if (file.fail()) {
perror(filePath.c_str());
return false;
}
file.seekg(0, std::ios::end);
int fileSize = file.tellg();
file.seekg(0, std::ios::beg);
fileSize = fileSize - file.tellg();
buffer.resize(fileSize);
file.read((char *)&(buffer[0]), fileSize);
file.close();
return true;
}
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