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Help => Graphics => Topic started by: battosaijenkins on May 29, 2020, 08:10:31 pm

Title: sfml gradient shaders question
Post by: battosaijenkins on May 29, 2020, 08:10:31 pm

Hello, I posted a question in github SFML Gradient shaders but was told to post here instead. I was wondering if it's possible to pass an sf::Transform into the draw function along with the shader?

For example normal draw I would pass a transform like:

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window.draw(circle, transform);

but with shaders that 2nd parameter is already taken up like

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window.draw(circle, &shader);

 and I cant add a third parameter. I read somewhere that I could use

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shader.setUniform("matrix", sf::Glsl::Mat4(transform));

but I added

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"uniform mat4 matrix;"

in const char RadialGradient[] but I'm getting Uniform "matrix" not found in shader. Am I doing it wrong, or overdoing it or missing something?

Title: Re: sfml gradient shaders question
Post by: G. on May 29, 2020, 08:56:04 pm

Hey. You can use an sf::RenderStates (https://www.sfml-dev.org/documentation/2.5.1/classsf_1_1RenderStates.php) and pass it to your draw function instead of only the shader.

Title: Re: sfml gradient shaders question
Post by: battosaijenkins on May 30, 2020, 02:22:46 am

So I cant use sf::Transform?

Title: Re: sfml gradient shaders question
Post by: battosaijenkins on May 30, 2020, 03:01:25 am

Oh I see what you mean. You're saying I would use sf::RenderStates state and then use state.transform = transform and also use &shader in state.shader then pass state like window.draw(circle, state);? I think I understand now, thanks.