SFML加载着色器错误

Question

So i am working on my game project using SFML and I tried to implement a blur shader. I have no idea why , but this block of code makes the program show a white screen and then close.I didn't even use the shader to draw anything , just the fact that I am trying to load it gives the unexpected result :( .

void button::setText(std::string _text)
{
    text.setString(_text);
    text.setFont(font);
    text.setCharacterSize(80);
    text.move(0,-(text.getLocalBounds().top));
    text.setColor(sf::Color(255,255,255,255));
    width=text.getLocalBounds().width+text.getLocalBounds().left;
    height=text.getLocalBounds().height+text.getLocalBounds().top;
    rndtexture.create(width, height);
    rndtexture.setSmooth(true);
    rndtexture.clear(sf::Color::Transparent);
    rndtexture.draw(text);
    rndtexture.display();
    rTexture=rndtexture.getTexture();
    spriteR.setTexture(rTexture);

    rndtexture.clear(sf::Color::Transparent);
    text.setColor(sf::Color(0,0,0,100));
    rndtexture.draw(text);
    rndtexture.display();
    pTexture=rndtexture.getTexture();
    spriteP.setTexture(pTexture);

    //commenting this out will make it work just fine
    if (!shader.loadFromFile("shader.frag", sf::Shader::Type::Fragment))
    {
        std::cout<<"lol";
    }
    //

    shader.setParameter("texture", sf::Shader::CurrentTexture);
    shader.setParameter("blur_radius", 5.0);
}

This is my shader file:

uniform sampler2D texture;
uniform float blur_radius;

void main()
{
    vec2 offx = vec2(blur_radius, 0.0);
    vec2 offy = vec2(0.0, blur_radius);

    vec4 pixel = texture2D(texture, gl_TexCoord[0].xy) * 4.0 +
                 texture2D(texture, gl_TexCoord[0].xy - offx) * 2.0 +
                 texture2D(texture, gl_TexCoord[0].xy + offx) * 2.0 +
                 texture2D(texture, gl_TexCoord[0].xy - offy) * 2.0 +
                 texture2D(texture, gl_TexCoord[0].xy + offy) * 2.0 +
                 texture2D(texture, gl_TexCoord[0].xy - offx - offy) * 1.0 +
                 texture2D(texture, gl_TexCoord[0].xy - offx + offy) * 1.0 +
                 texture2D(texture, gl_TexCoord[0].xy + offx - offy) * 1.0 +
                 texture2D(texture, gl_TexCoord[0].xy + offx + offy) * 1.0;

    gl_FragColor = gl_Color * (pixel / 16.0);
}

What is wrong with this.. ?

Answer 1

What's the return value when you call:

sf::Shader::isAvailable()

Make sure you can use a shader program before you call it. Also, a shader can't crash a program, so it's definitely not your shader. If something was wrong with your shader, it wouldn't compile. If your shader didn't compile, then SFML automatically switches to a built-in shader.