Merge pull request #125 from alphastrata/new-shaders

New shaders

Author: alphastrata

assets/shaders/myshader_2d.wgsl

@@ -1,14 +1,20 @@
-#import bevy_sprite::mesh2d_view_bindings::globals
-#import bevy_sprite::mesh2d_vertex_output::VertexOutput
-#import shadplay::shader_utils::common::{NEG_HALF_PI, shader_toy_default, rotate2D}
+/// ***************************** ///
+/// THIS IS THE DEFAULT 2D SHADER ///
+/// You can always get back to this with `python3 scripts/reset-2d.py` ///
+/// ***************************** ///
+
+#import bevy_sprite::mesh2d_view_bindings::globals 
+#import shadplay::shader_utils::common::{NEG_HALF_PI, shader_toy_default, rotate2D, TWO_PI}
 #import bevy_render::view::View
+#import bevy_sprite::mesh2d_vertex_output::VertexOutput
 
 @group(0) @binding(0) var<uniform> view: View;
 
-const SPEED: f32 = 1.0;
+const SPEED:f32 = 1.0;
 
 @fragment
 fn fragment(in: VertexOutput) -> @location(0) vec4<f32> {
+    // ensure our uv coords match shadertoy/the-lil-book-of-shaders
     var uv = in.uv;
     uv = (uv * 2.0) - 1.0;
     let resolution = view.viewport.zw;
@@ -17,4 +23,5 @@ fn fragment(in: VertexOutput) -> @location(0) vec4<f32> {
     uv *= rotate2D(NEG_HALF_PI);
 
     return vec4f(shader_toy_default(t, uv), 0.3);
-}
+}    
+    

assets/shaders/shadertoy-ports/fire_tornado.wgsl

@@ -0,0 +1,115 @@
+//
+// Port of a "Fireball" shader.
+// Original source: https://www.shadertoy.com/view/XtGGRt by boywonder
+//
+
+#import bevy_sprite::mesh2d_view_bindings::globals
+#import bevy_sprite::mesh2d_vertex_output::VertexOutput
+#import bevy_render::view::View
+#import shadplay::shader_utils::common::{PI, TAU, sdBox, rotate2D_clockwise, fbm_fireball}
+
+@group(0) @binding(0) var<uniform> view: View;
+// TODO: Mouse input is not yet fully handled in this port.
+// To enable mouse rotation, you would need to:
+// 1. Ensure the necessary mouse data (position and button state) is sent to the shader.
+// 2. Uncomment the mouse uniform binding below.
+// 3. Uncomment the mouse rotation logic in the fragment shader's main loop.
+// #import shadplay::shader_utils::common::YourShader2D
+// @group(3) @binding(0) var<uniform> mouse: YourShader2D;
+
+const EPSILON: f32 = 1e-6;
+
+// A private global variable to accumulate color during raymarching.
+// This is a common pattern in Shadertoy ports where functions have side effects.
+var<private> col: vec3<f32>;
+
+// --- Helper Functions ---
+
+/// Macro replacement for `(sin(v)*.5+.5)` from the original shader.
+fn s1(v: vec3<f32>) -> vec3<f32> {
+    return sin(v) * 0.5 + 0.5;
+}
+
+/// The main Signed Distance Function for the fireball scene.
+fn sdFireBall(p: vec3<f32>) -> f32 {
+  var p_mut = p;
+  p_mut.y -= -1.0;
+  var q = p_mut;
+  
+  let T = globals.time;
+  let h = 5.0;
+  let range = smoothstep(-h, h, p_mut.y);
+  let w = range * 4.0 + 1.0;
+  let thick = range * 4.0 + 1.0;
+  
+  let new_xz = rotate2D_clockwise(q.y * 1.0 - T * 2.0) * q.xz;
+  q.x = new_xz.x;
+  q.z = new_xz.y;
+
+  var d = sdBox(q, vec3<f32>(w, h, thick));
+  let d1 = sdBox(q - vec3<f32>(0.0, 1.0, 0.0), vec3<f32>(w, h, thick) * vec3<f32>(0.7, 2.0, 0.7));
+  d = max(d, -d1);
+  
+  d += fbm_fireball(p_mut * 3.0, T) * 0.5;
+
+  d = abs(d) * 0.1 + 0.01;
+
+  let c = s1(vec3<f32>(3.0, 2.0, 1.0) + (p_mut.y + p_mut.z) * 0.5 - T * 2.0);
+  // Accumulate color as a side effect.
+  col += pow(1.3 / d, 2.0) * c;
+
+  return d;
+}
+
+
+// --- Main Fragment Shader ---
+
+@fragment
+fn fragment(in: VertexOutput) -> @location(0) vec4<f32> {
+    let R = view.viewport.zw;
+    // Normalize UVs to -1.0 to 1.0, accounting for aspect ratio.
+    var uv = (in.uv * R * 2.0 - R) / R.y;
+    uv.y *= -1.0; // Invert Y-axis to correct orientation.
+    // let m = (mouse.mouse_pos * 2.0 - R) / R * PI * 2.0;
+
+    // Reset the global color accumulator for this fragment.
+    col = vec3<f32>(0.0);
+    var O: vec4<f32>;
+
+    // Setup camera ray origin and direction.
+    var ro = vec3<f32>(0.0, 0.0, -10.0);
+    let rd = normalize(vec3<f32>(uv, 1.0));
+
+    // Raymarch the scene.
+    let zMax = 20.0;
+    var z = 0.1;
+
+    for(var i = 0.0; i < 100.0; i = i + 1.0) {
+        var p = ro + rd * z;
+
+        // Mouse interaction is disabled for now.
+        // if (mouse.button_pressed > 0.0) {
+        //     let m_x_rot = rotate2D_clockwise(m.x);
+        //     let new_xz = m_x_rot * p.xz;
+        //     p.x = new_xz.x;
+        //     p.z = new_xz.y;
+
+        //     let m_y_rot = rotate2D_clockwise(m.y);
+        //     let new_yz = m_y_rot * p.yz;
+        //     p.y = new_yz.x;
+        //     p.z = new_yz.y;
+        // }
+
+        let d = sdFireBall(p);
+        
+        if(d < EPSILON || z > zMax) {
+            break;
+        }
+        z += d;
+    }
+
+    // Final color processing (tonemapping).
+    col = tanh(col / 9e4);
+    O = vec4<f32>(col, 1.0);
+    return O;
+}