haze

src/scenes/shader/tile_frag.glsl

@@ -4,6 +4,7 @@
 
 in vec2 v_uv;
 flat in uint v_tileidx;
+in float v_fade;
 out vec4 pixcolor;
 uniform sampler2DArray t_tiles;
 uniform b_constants {
@@ -11,6 +12,8 @@ uniform b_constants {
   float R1;
   float R2;
   float R3;
+  float haze;
+  vec4 hazecolor;
 };
 uniform b_locals {
   uint millis;
@@ -24,5 +27,6 @@ void main() {
     anim_uv = vec2(v_uv.x, v_uv.y + float(millis % MILLIS_PER_TILE) / MILLIS_PER_TILE);
   }
 
-  pixcolor = texture(t_tiles, vec3(anim_uv.x, 1.0 - anim_uv.y, v_tileidx));
+  vec4 texcolor = texture(t_tiles, vec3(anim_uv.x, 1.0 - anim_uv.y, v_tileidx));
+  pixcolor = mix(texcolor, hazecolor, v_fade);
 }

src/scenes/shader/torus_vertex.glsl

@@ -8,7 +8,9 @@ in vec2 a_uv;
 in uint a_tileidx;
 out vec2 v_uv;
 flat out uint v_tileidx;
+out float v_fade;
 uniform b_trans {
+  mat4 u_viewmodel;
   mat4 u_matrix;
 };
 uniform b_constants {
@@ -16,6 +18,8 @@ uniform b_constants {
   float R1;
   float R2;
   float R3;
+  float haze;
+  vec4 hazecolor;
 };
 uniform b_locals {
   uint millis;
@@ -38,5 +42,9 @@ void main() {
   float height = R2 * 4 * TWO_PI_CIRC;
   vec3 normal = vec3(toroid(thetaphi, 0, height, height)) *
                 vec3(R2 / R3, 1.0, 1.0);
-  gl_Position = u_matrix * vec4(toroid(thetaphi, R1, R2, R3) + a_pos.z * normal, 1.0);
+  vec4 model_pos = vec4(toroid(thetaphi, R1, R2, R3) + a_pos.z * normal, 1.0);
+  gl_Position = u_matrix * model_pos;
+
+  vec4 view_pos = u_viewmodel * model_pos;
+  v_fade = min(1.0, length(view_pos.xyz) / R1 / 2 * haze);
 }

src/scenes/world.rs

@@ -29,6 +29,9 @@ const R1: f32 = 256.0;
 const R2: f32 = 64.0;
 const R3: f32 = 128.0;
 
+//const SKY_COLOR: [f32; 4] = [0.15, 0.15, 0.75, 1.0];
+const SKY_COLOR: [f32; 4] = [0.005, 0.005, 0.01, 1.0];
+
 gfx_defines! {
   vertex Vertex {
     pos: [f32; 3] = "a_pos",
@@ -41,6 +44,8 @@ gfx_defines! {
     r1: f32 = "R1",
     r2: f32 = "R2",
     r3: f32 = "R3",
+    haze: f32 = "haze",
+    hazecolor: [f32; 4] = "hazecolor",
   }
 
   constant Locals {
@@ -157,7 +162,9 @@ impl<D: gfx::Device, F: gfx::Factory<D::Resources>> WorldScene<D, F> {
                                           pipe::new())
                   .expect("create pipeline"),
       camera: na::Matrix4::one(),
-      constants: Constants { anim: ANIMDATA, r1: R1, r2: R2, r3: R3},
+      constants: Constants { anim: ANIMDATA,
+                             r1: R1, r2: R2, r3: R3,
+                             haze: 1.0/2.0f32.sqrt(), hazecolor: SKY_COLOR },
       constants_buffer: factory.create_constant_buffer(1),
       constants_dirty: true,
       locals: factory.create_constant_buffer(1),
@@ -258,6 +265,17 @@ impl<D: gfx::Device,
         self.constants = Constants { r1: R1 * 16.0, r2: R2 * 16.0, r3: R3 * 16.0, ..self.constants };
         self.constants_dirty = true;
       },
+
+      Piston(Input::Press(Button::Keyboard(Key::H))) => {
+        self.constants = Constants { haze: self.constants.haze * 2.0f32.sqrt().sqrt(), ..self.constants };
+        println!("haze: {}", self.constants.haze);
+        self.constants_dirty = true;
+      },
+      Piston(Input::Press(Button::Keyboard(Key::N))) => {
+        self.constants = Constants { haze: self.constants.haze / 2.0f32.sqrt().sqrt(), ..self.constants };
+        println!("haze: {}", self.constants.haze);
+        self.constants_dirty = true;
+      },
       _ => ()
     }
   }
@@ -327,6 +345,8 @@ impl<D: gfx::Device,
             target: &gfx::handle::RenderTargetView<D::Resources, view::ColorFormat>,
             depth: &gfx::handle::DepthStencilView<D::Resources, view::DepthFormat>) {
 
+    encoder.clear(&target, SKY_COLOR);
+    encoder.clear_depth(&depth, 1.0);
     let pipe = pipe::Data {
       vbuf: self.vbuf.clone(),
       trans: trans.clone(),