Basic amethyst_renderer example with revamped API

amethyst_renderer_new.rs

//! Launches an empty renderer window with a deferred pipeline and white color.
//!
//! Uses `rayon` and `num_cpus` internally to batch `gfx::Encoder`s efficiently
//! and maximize parallelism. Haven't uploaded changes to GitHub since Amethyst is
//! completely broken with these changes. This is due to `gfx_device` and other
//! rendering stuff being directly inside the engine, instead of a `RenderingSystem`
//! where it really belongs. Some restructuring is necessary to fix this design
//! oversight and get this new renderer to work.

extern crate amethyst_renderer as renderer;
extern crate winit;

use renderer::{RendererBuilder, Layer, Target};
use renderer::pass::{BlitLayer, ClearTarget, DrawFlat, DeferredLighting};
use winit::ElementState::Pressed;
use winit::VirtualKeyCode as Key;
use winit::{Event, WindowBuilder};

fn main() { 
    let builder = WindowBuilder::new()
        .with_title("Amethyst Renderer Demo")
        .with_dimensions(1024, 768);

    let (window, mut renderer) = RendererBuilder::new(builder)
        .build()
        .expect("Could not build renderer");
    
    // Create GPU resources here, not implemented.

    let pipe = renderer.create_pipeline()
        .with_target(Target::new("gbuffer")
            .with_num_color_bufs(4)
            .with_depth_buf(true))
        .with_layer(Layer::with_target("gbuffer")
            .with_pass(ClearTarget::with_values([0.0; 4], 0.0))
            .with_pass(DrawFlat::with_camera("main_camera")))
        .with_layer(Layer::with_target("main")
            .with_pass(BlitTarget::from_target_color_buf("gbuffer", 2))
            .with_pass(DeferredLighting::new("main_camera", "gbuffer", "scene")))
        .build()
        .expect("Could not build pipeline");
  
    // Build initial scene, not implemented.
  
    'main: loop {
        for event in window.poll_events() {
            match event {
                Event::Closed => break 'main,
                Event::KeyboardInput(Pressed, _, Some(Key::Escape)) => break 'main,
                _ => (),
            }
        }
        
        // Modify scene and create/destroy GPU resources as needed.

        renderer.draw(&pipe); // Pass scene and delta time here, eventually.
        window.swap_buffers().expect("Window error");
    }
}