#[macro_use]
extern crate glium;
use glium::Surface;
use glium::glutin;
mod support;
mod fxaa {
use glium::{self, Surface};
use glium::backend::Facade;
use glium::backend::Context;
use glium::framebuffer::SimpleFrameBuffer;
use std::cell::RefCell;
use std::rc::Rc;
pub struct FxaaSystem {
context: Rc<Context>,
vertex_buffer: glium::VertexBuffer<SpriteVertex>,
index_buffer: glium::IndexBuffer<u16>,
program: glium::Program,
target_color: RefCell<Option<glium::texture::Texture2d>>,
target_depth: RefCell<Option<glium::framebuffer::DepthRenderBuffer>>,
}
#[derive(Copy, Clone)]
struct SpriteVertex {
position: [f32; 2],
i_tex_coords: [f32; 2],
}
implement_vertex!(SpriteVertex, position, i_tex_coords);
impl FxaaSystem {
pub fn new<F>(facade: &F) -> FxaaSystem where F: Facade + Clone {
FxaaSystem {
context: facade.get_context().clone(),
vertex_buffer: glium::VertexBuffer::new(facade,
&[
SpriteVertex { position: [-1.0, -1.0], i_tex_coords: [0.0, 0.0] },
SpriteVertex { position: [-1.0, 1.0], i_tex_coords: [0.0, 1.0] },
SpriteVertex { position: [ 1.0, 1.0], i_tex_coords: [1.0, 1.0] },
SpriteVertex { position: [ 1.0, -1.0], i_tex_coords: [1.0, 0.0] }
]
).unwrap(),
index_buffer: glium::index::IndexBuffer::new(facade,
glium::index::PrimitiveType::TriangleStrip, &[1 as u16, 2, 0, 3]).unwrap(),
program: program!(facade,
100 => {
vertex: r"
#version 100
attribute vec2 position;
attribute vec2 i_tex_coords;
varying vec2 v_tex_coords;
void main() {
gl_Position = vec4(position, 0.0, 1.0);
v_tex_coords = i_tex_coords;
}
",
fragment: r"
#version 100
precision mediump float;
uniform vec2 resolution;
uniform sampler2D tex;
uniform int enabled;
varying vec2 v_tex_coords;
#define FXAA_REDUCE_MIN (1.0/ 128.0)
#define FXAA_REDUCE_MUL (1.0 / 8.0)
#define FXAA_SPAN_MAX 8.0
vec4 fxaa(sampler2D tex, vec2 fragCoord, vec2 resolution,
vec2 v_rgbNW, vec2 v_rgbNE,
vec2 v_rgbSW, vec2 v_rgbSE,
vec2 v_rgbM) {
vec4 color;
mediump vec2 inverseVP = vec2(1.0 / resolution.x, 1.0 / resolution.y);
vec3 rgbNW = texture2D(tex, v_rgbNW).xyz;
vec3 rgbNE = texture2D(tex, v_rgbNE).xyz;
vec3 rgbSW = texture2D(tex, v_rgbSW).xyz;
vec3 rgbSE = texture2D(tex, v_rgbSE).xyz;
vec4 texColor = texture2D(tex, v_rgbM);
vec3 rgbM = texColor.xyz;
vec3 luma = vec3(0.299, 0.587, 0.114);
float lumaNW = dot(rgbNW, luma);
float lumaNE = dot(rgbNE, luma);
float lumaSW = dot(rgbSW, luma);
float lumaSE = dot(rgbSE, luma);
float lumaM = dot(rgbM, luma);
float lumaMin = min(lumaM, min(min(lumaNW, lumaNE), min(lumaSW, lumaSE)));
float lumaMax = max(lumaM, max(max(lumaNW, lumaNE), max(lumaSW, lumaSE)));
mediump vec2 dir;
dir.x = -((lumaNW + lumaNE) - (lumaSW + lumaSE));
dir.y = ((lumaNW + lumaSW) - (lumaNE + lumaSE));
float dirReduce = max((lumaNW + lumaNE + lumaSW + lumaSE) *
(0.25 * FXAA_REDUCE_MUL), FXAA_REDUCE_MIN);
float rcpDirMin = 1.0 / (min(abs(dir.x), abs(dir.y)) + dirReduce);
dir = min(vec2(FXAA_SPAN_MAX, FXAA_SPAN_MAX),
max(vec2(-FXAA_SPAN_MAX, -FXAA_SPAN_MAX),
dir * rcpDirMin)) * inverseVP;
vec3 rgbA = 0.5 * (
texture2D(tex, fragCoord * inverseVP + dir * (1.0 / 3.0 - 0.5)).xyz +
texture2D(tex, fragCoord * inverseVP + dir * (2.0 / 3.0 - 0.5)).xyz);
vec3 rgbB = rgbA * 0.5 + 0.25 * (
texture2D(tex, fragCoord * inverseVP + dir * -0.5).xyz +
texture2D(tex, fragCoord * inverseVP + dir * 0.5).xyz);
float lumaB = dot(rgbB, luma);
if ((lumaB < lumaMin) || (lumaB > lumaMax))
color = vec4(rgbA, texColor.a);
else
color = vec4(rgbB, texColor.a);
return color;
}
void main() {
vec2 fragCoord = v_tex_coords * resolution;
vec4 color;
if (enabled != 0) {
vec2 inverseVP = 1.0 / resolution.xy;
mediump vec2 v_rgbNW = (fragCoord + vec2(-1.0, -1.0)) * inverseVP;
mediump vec2 v_rgbNE = (fragCoord + vec2(1.0, -1.0)) * inverseVP;
mediump vec2 v_rgbSW = (fragCoord + vec2(-1.0, 1.0)) * inverseVP;
mediump vec2 v_rgbSE = (fragCoord + vec2(1.0, 1.0)) * inverseVP;
mediump vec2 v_rgbM = vec2(fragCoord * inverseVP);
color = fxaa(tex, fragCoord, resolution, v_rgbNW, v_rgbNE, v_rgbSW,
v_rgbSE, v_rgbM);
} else {
color = texture2D(tex, v_tex_coords);
}
gl_FragColor = color;
}
"
}
).unwrap(),
target_color: RefCell::new(None),
target_depth: RefCell::new(None),
}
}
}
pub fn draw<T, F, R>(system: &FxaaSystem, target: &mut T, enabled: bool, mut draw: F)
-> R where T: Surface, F: FnMut(&mut SimpleFrameBuffer) -> R
{
let target_dimensions = target.get_dimensions();
let mut target_color = system.target_color.borrow_mut();
let mut target_depth = system.target_depth.borrow_mut();
{
let clear = if let &Some(ref tex) = &*target_color {
tex.get_width() != target_dimensions.0 ||
tex.get_height().unwrap() != target_dimensions.1
} else {
false
};
if clear { *target_color = None; }
}
{
let clear = if let &Some(ref tex) = &*target_depth {
tex.get_dimensions() != target_dimensions
} else {
false
};
if clear { *target_depth = None; }
}
if target_color.is_none() {
let texture = glium::texture::Texture2d::empty(&system.context,
target_dimensions.0 as u32,
target_dimensions.1 as u32).unwrap();
*target_color = Some(texture);
}
let target_color = target_color.as_ref().unwrap();
if target_depth.is_none() {
let texture = glium::framebuffer::DepthRenderBuffer::new(&system.context,
glium::texture::DepthFormat::I24,
target_dimensions.0 as u32,
target_dimensions.1 as u32).unwrap();
*target_depth = Some(texture);
}
let target_depth = target_depth.as_ref().unwrap();
let output = draw(&mut SimpleFrameBuffer::with_depth_buffer(&system.context, target_color,
target_depth).unwrap());
let uniforms = uniform! {
tex: &*target_color,
enabled: if enabled { 1i32 } else { 0i32 },
resolution: (target_dimensions.0 as f32, target_dimensions.1 as f32)
};
target.draw(&system.vertex_buffer, &system.index_buffer, &system.program, &uniforms,
&Default::default()).unwrap();
output
}
}
fn main() {
use glium::DisplayBuild;
println!("This example demonstrates FXAA. Is is an anti-aliasing technique done at the \
post-processing stage. This example draws the teapot to a framebuffer and then \
copies from the texture to the main framebuffer by applying a filter to it.\n\
You can use the space bar to switch fxaa on and off.");
let display = glutin::WindowBuilder::new()
.with_depth_buffer(24)
.build_glium()
.unwrap();
let vertex_buffer = support::load_wavefront(&display, include_bytes!("support/teapot.obj"));
let program = program!(&display,
140 => {
vertex: "
#version 140
uniform mat4 persp_matrix;
uniform mat4 view_matrix;
in vec3 position;
in vec3 normal;
out vec3 v_position;
out vec3 v_normal;
void main() {
v_position = position;
v_normal = normal;
gl_Position = persp_matrix * view_matrix * vec4(v_position * 0.005, 1.0);
}
",
fragment: "
#version 140
in vec3 v_normal;
out vec4 f_color;
const vec3 LIGHT = vec3(-0.2, 0.8, 0.1);
void main() {
float lum = max(dot(normalize(v_normal), normalize(LIGHT)), 0.0);
vec3 color = (0.3 + 0.7 * lum) * vec3(1.0, 1.0, 1.0);
f_color = vec4(color, 1.0);
}
",
},
110 => {
vertex: "
#version 110
uniform mat4 persp_matrix;
uniform mat4 view_matrix;
attribute vec3 position;
attribute vec3 normal;
varying vec3 v_position;
varying vec3 v_normal;
void main() {
v_position = position;
v_normal = normal;
gl_Position = persp_matrix * view_matrix * vec4(v_position * 0.005, 1.0);
}
",
fragment: "
#version 110
varying vec3 v_normal;
const vec3 LIGHT = vec3(-0.2, 0.8, 0.1);
void main() {
float lum = max(dot(normalize(v_normal), normalize(LIGHT)), 0.0);
vec3 color = (0.3 + 0.7 * lum) * vec3(1.0, 1.0, 1.0);
gl_FragColor = vec4(color, 1.0);
}
",
},
100 => {
vertex: "
#version 100
uniform lowp mat4 persp_matrix;
uniform lowp mat4 view_matrix;
attribute lowp vec3 position;
attribute lowp vec3 normal;
varying lowp vec3 v_position;
varying lowp vec3 v_normal;
void main() {
v_position = position;
v_normal = normal;
gl_Position = persp_matrix * view_matrix * vec4(v_position * 0.005, 1.0);
}
",
fragment: "
#version 100
varying lowp vec3 v_normal;
const lowp vec3 LIGHT = vec3(-0.2, 0.8, 0.1);
void main() {
lowp float lum = max(dot(normalize(v_normal), normalize(LIGHT)), 0.0);
lowp vec3 color = (0.3 + 0.7 * lum) * vec3(1.0, 1.0, 1.0);
gl_FragColor = vec4(color, 1.0);
}
",
},
).unwrap();
let mut camera = support::camera::CameraState::new();
let fxaa = fxaa::FxaaSystem::new(&display);
let mut fxaa_enabled = true;
support::start_loop(|| {
camera.update();
let uniforms = uniform! {
persp_matrix: camera.get_perspective(),
view_matrix: camera.get_view(),
};
let params = glium::DrawParameters {
depth: glium::Depth {
test: glium::DepthTest::IfLess,
write: true,
.. Default::default()
},
.. Default::default()
};
let mut target = display.draw();
fxaa::draw(&fxaa, &mut target, fxaa_enabled, |target| {
target.clear_color_and_depth((0.0, 0.0, 0.0, 0.0), 1.0);
target.draw(&vertex_buffer,
&glium::index::NoIndices(glium::index::PrimitiveType::TrianglesList),
&program, &uniforms, ¶ms).unwrap();
});
target.finish().unwrap();
for event in display.poll_events() {
match event {
glutin::Event::Closed => return support::Action::Stop,
glutin::Event::KeyboardInput(glutin::ElementState::Pressed, _, Some(glutin::VirtualKeyCode::Space)) => {
fxaa_enabled = !fxaa_enabled;
println!("FXAA is now {}", if fxaa_enabled { "enabled" } else { "disabled" });
},
ev => camera.process_input(&ev),
}
}
support::Action::Continue
});
}