Merge pull request #3 from LykenSol/MdXSzS

Ported "Galaxy of Universes" (https://www.shadertoy.com/view/MdXSzS).

Author: eddyb

shaders/src/galaxy_of_universes.rs

@@ -0,0 +1,76 @@
+//! Ported to Rust from <https://www.shadertoy.com/view/MdXSzS>
+//!
+//! Original comment:
+//! ```glsl
+//! // https://www.shadertoy.com/view/MdXSzS
+//! // The Big Bang - just a small explosion somewhere in a massive Galaxy of Universes.
+//! // Outside of this there's a massive galaxy of 'Galaxy of Universes'... etc etc. :D
+//!
+//! // To fake a perspective it takes advantage of the screen being wider than it is tall.
+//! ```
+
+use shared::*;
+use spirv_std::glam::{Mat2, Vec2, Vec3, Vec3Swizzles, Vec4};
+
+// Note: This cfg is incorrect on its surface, it really should be "are we compiling with std", but
+// we tie #[no_std] above to the same condition, so it's fine.
+#[cfg(target_arch = "spirv")]
+use spirv_std::num_traits::Float;
+
+pub struct Inputs {
+    pub resolution: Vec3,
+    pub time: f32,
+}
+
+impl Inputs {
+    pub fn main_image(&self, frag_color: &mut Vec4, frag_coord: Vec2) {
+        let uv: Vec2 = (frag_coord / self.resolution.xy()) - Vec2::splat(0.5);
+        let t: f32 = self.time * 0.1 + (0.25 + 0.05 * (self.time * 0.1).sin());
+        let si: f32 = t.sin();
+        let co: f32 = t.cos();
+        let ma: Mat2 = Mat2::from_cols_array(&[co, si, -si, co]);
+
+        let mut v1: f32 = 0.0;
+        let mut v2: f32 = 0.0;
+        let mut v3: f32 = 0.0;
+
+        let mut s: f32 = 0.0;
+
+        let mut i = 0;
+        while i < 90 {
+            let mut p: Vec3 = s * uv.extend(0.0);
+            p = (ma.transpose() * p.xy()).extend(p.z);
+            p += Vec3::new(0.22, 0.3, s - 1.5 - (self.time * 0.13).sin() * 0.1);
+            {
+                let mut i = 0;
+                while i < 8 {
+                    p = p.abs() / p.dot(p) - Vec3::splat(0.659);
+                    i += 1;
+                }
+            }
+            v1 += p.dot(p) * 0.0015 * (1.8 + ((uv * 13.0).length() + 0.5 - self.time * 0.2).sin());
+            v2 += p.dot(p) * 0.0013 * (1.5 + ((uv * 14.5).length() + 1.2 - self.time * 0.3).sin());
+            v3 += (p.xy() * 10.0).length() * 0.0003;
+            s += 0.035;
+            i += 1;
+        }
+
+        let len: f32 = uv.length();
+        v1 *= smoothstep(0.7, 0.0, len);
+        v2 *= smoothstep(0.5, 0.0, len);
+        v3 *= smoothstep(0.9, 0.0, len);
+
+        let col: Vec3 = Vec3::new(
+            v3 * (1.5 + (self.time * 0.2).sin() * 0.4),
+            (v1 + v3) * 0.3,
+            v2,
+        ) + Vec3::splat(smoothstep(0.2, 0.0, len) * 0.85)
+            + Vec3::splat(smoothstep(0.0, 0.6, v3) * 0.3);
+
+        *frag_color = col
+            .abs()
+            .powf_vec(Vec3::splat(1.2))
+            .min(Vec3::splat(1.0))
+            .extend(1.0);
+    }
+}

shaders/src/lib.rs

@@ -11,6 +11,7 @@ pub mod a_lot_of_spheres;
 pub mod a_question_of_time;
 pub mod apollonian;
 pub mod clouds;
+pub mod galaxy_of_universes;
 pub mod heart;
 pub mod mandelbrot_smooth;
 pub mod phantom_star;
@@ -48,7 +49,7 @@ impl Channel for RgbCube {
 
 pub fn fs(constants: &ShaderConstants, mut frag_coord: Vec2) -> Vec4 {
     const COLS: usize = 4;
-    const ROWS: usize = 3;
+    const ROWS: usize = 4;
 
     let resolution = Vec3::new(
         constants.width as f32 / COLS as f32,
@@ -105,6 +106,7 @@ pub fn fs(constants: &ShaderConstants, mut frag_coord: Vec2) -> Vec4 {
             mouse,
         }
         .main_image(&mut color, frag_coord),
+        12 => galaxy_of_universes::Inputs { resolution, time }.main_image(&mut color, frag_coord),
         _ => {}
     }
     pow(color.truncate(), 2.2).extend(color.w)