[SOLVED] sf:Glsel::Vec2 won't compile

[AncientGrief]

Hi,

I am trying to learn GLSL with SFML, but this line won't compile:

shader.setUniform(sf::Glsl::Vec2(800.0f,600.0f));
 

What am I missing?!

This is the error I get form MinGW on Windows 10

Code: [Select]

main.cpp:22:52: error: no matching function for call to 'sf::Shader::setUniform(sf::Glsl::Vec2)'

Regards
AncientGrief

P.S. This is the tutorial I am going through:
http://gamedevelopment.tutsplus.com/tutorials/a-beginners-guide-to-coding-graphics-shaders--cms-23313

[Arcade]

Your compiler error is telling you why it won't compile. There is no function called setUniform in sf::Shader. Maybe you are looking for the function setParameter?

Edit: I guess I should add that I'm assuming you are using a released version of SFML. I believe the shader API has changed in the master trunk on github (which does include a setUniform function). If you want to use the new API I believe you need to build SFML from there.

[AncientGrief]

Thanks for the answer. yes it's the master trunk I am using...

Just reset to 2.3.2 Release (thanks @ IRC @ Eremiell) ... seems to work with setParameter() ...at least it compiles

EDIT:
But it still doesn't work ...
My GLSL fragment shader:

Code: [Select]

uniform sampler2D iChannel0;
uniform vec3 iResolution;

void mainImage( out vec4 fragColor, in vec2 fragCoord )
{
    vec2 xy = iResolution.xy;
    xy.y = 1.0 - xy.y;
   
    vec4 texColor = texture2D(iChannel0, xy);
    texColor.b = xy.x;
   
    fragColor = texColor;
}

Edit: But it still does not work:

The shader code:

    text.loadFromFile("texture.png");
    sprite.setTexture(text);
    shader.loadFromFile("shader.frag", sf::Shader::Type::Fragment))

    shader.setParameter("iResolution", 800.0f, 600.0f);
    shader.setParameter("iChannel0",sf::Shader::CurrentTexture);

//....

window.draw(sprite,&shader);
 

Edit2: I just want the texture to be stretched to the window size, like in the tutorial...

[Laurent]

iResolution being 800x600 is clearly wrong (and why declared as a vec3?), given that you use it as normalized coordinates in the shader.

[Nexus]

I am trying to learn GLSL with SFML, but this line won't compile:

shader.setUniform(sf::Glsl::Vec2(800.0f,600.0f));
 

What am I missing?!

The first parameter -- the uniform name.

Don't use setParameter(), it's deprecated. Upgrade SFML to the latest master if necessary and use setUniform().

[AncientGrief]

...
What am I missing?!

The first parameter -- the uniform name.

Don't use setParameter(), it's deprecated. Upgrade SFML to the latest master if necessary and use setUniform().

Okay now I feel really stupid ... I shouldn't have coded yesterday ... thank you Nexus

iResolution being 800x600 is clearly wrong (and why declared as a vec3?), given that you use it as normalized coordinates in the shader.

Yes you're right, I orientated the iResolution to Shadertoys variable:

vec3    iResolution     image   The viewport resolution (z is pixel aspect ratio, usually 1.0)

But I figured it out, the shader variable names were wrong:

fragColor must be gl_FragColor

fragCoord.xy must be gl_TexCoord[0].xy
 

What is the best way to stretch the sprite to the window resolution (with shaders)?!

[Laurent]

What is the best way to stretch the sprite to the window resolution (with shaders)?!

Not with a fragment shader, which only deals with individual pixels.
Hardly with a vertex shader, which can only handle vertices one by one (you'd have to find a way to tell which corner is each vertex).
Possibly with a geometry shader, but I can't tell more about this subject

The best way is to do it in on C++ side.

[AncientGrief]

What is the best way to stretch the sprite to the window resolution (with shaders)?!

Not with a fragment shader, which only deals with individual pixels.
Hardly with a vertex shader, which can only handle vertices one by one (you'd have to find a way to tell which corner is each vertex).
Possibly with a geometry shader, but I can't tell more about this subject

The best way is to do it in on C++ side.

Thanks Laurent

I guess I will stick to SFML's features to achieve this, at least I can now continue to learn GLSL without headaches, I hope