gfx_graphics

Maintainers: @Potpourri, @kvark, @bvssvni

The implementation of a piston-graphics back-end using Gfx.

API Documentation

Dependency graph

How to contribute

lib.rs:

A Piston 2D graphics back-end using gfx-rs.

Piston-Graphics is a generic library for 2D, part of the Piston ecosystem. The generic abstraction creates triangles that are sent to the back-end. Triangles are sent through the Graphics trait.

How to use gfx_graphics

If you are using the piston_window library, a Gfx2d object is created for you. All you need to do is call e.draw_2d(|c, g| { ... });

If you are not using a window wrapper, you need to create Gfx2d and GfxGraphics.

1. Create a Gfx2d object before the event loop
2. Call Gfx2d::draw with args.viewport() from the render event.

Example:

let mut g2d = Gfx2d::new(api_version, &mut factory);
let mut events = window.events();
while let Some(e) = events.next(&mut window) {
    if let Some(args) = e.render_args() {
        g2d.draw(&mut encoder, &output_color, &output_stencil, args.viewport(), |c, g| {
            ...
        }
    }
}

For a working example, see "examples/draw_state.rs".

The closure |c, g| passes a Context and &mut GfxGraphics object. Context contains viewport, transform and draw state information.

When passing this to other functions, you usually write them as:

fn draw_something<G: Graphics>(c: &Context, g: &mut G) {
    ...
}

The purpose is to make code reusable across Piston 2D back-ends.

For more information, consult the documentation of Piston-Graphics.