feat: add CommonShaderBuilder and integrate Breathing Point shader

Author: orestesgaolin

assets/screenshots/breathing-point.png

@@ -1,9 +1,11 @@
 import 'package:flutter/material.dart';
+import 'package:flutter_shaders/flutter_shaders.dart';
+import 'package:google_fonts/google_fonts.dart';
 import 'dart:ui';
 import 'shader_builder.dart';
 
-class AiAssistantShaderBuilder extends CustomShaderBuilder {
-  const AiAssistantShaderBuilder();
+class CommonShaderBuilder extends CustomShaderBuilder {
+  const CommonShaderBuilder();
 
   @override
   bool get requiresImageSampler => false;
@@ -27,11 +29,17 @@ class AiAssistantShaderBuilder extends CustomShaderBuilder {
     double time,
     Widget? child,
   ) {
-    return ClipRect(
-      child: CustomPaint(
-        size: Size.infinite,
-        painter: _AiAssistantShaderPainter(shader),
-      ),
+    return AnimatedSampler(
+      (image, size, canvas) {
+        if (requiresImageSampler) {
+          shader.setImageSampler(0, image);
+        }
+        canvas.drawRect(
+          Rect.fromLTWH(0, 0, size.width, size.height),
+          Paint()..shader = shader,
+        );
+      },
+      child: child ?? const SizedBox.expand(),
     );
   }
 
@@ -40,20 +48,3 @@ class AiAssistantShaderBuilder extends CustomShaderBuilder {
     return null;
   }
 }
-
-class _AiAssistantShaderPainter extends CustomPainter {
-  final FragmentShader shader;
-
-  _AiAssistantShaderPainter(this.shader);
-
-  @override
-  void paint(Canvas canvas, Size size) {
-    canvas.drawRect(
-      Rect.fromLTWH(0, 0, size.width, size.height),
-      Paint()..shader = shader,
-    );
-  }
-
-  @override
-  bool shouldRepaint(covariant CustomPainter oldDelegate) => true;
-}

lib/clearly_bug_shader_builder.dart

@@ -8,15 +8,14 @@ import 'package:shaders/widgets/shader_card.dart';
 import 'package:shaders/widgets/widgets.dart';
 import 'package:shaders/meta/meta_tag_manager.dart';
 
+import 'common_shader_builder.dart';
 import 'shader_builder.dart';
 import 'crt_shader_builder.dart';
-import 'clearly_bug_shader_builder.dart';
 import 'noise_overlay_shader_builder.dart';
 import 'noise_shader_builder.dart';
 import 'ntsc_shader_builder.dart';
 import 'rings_shader_builder.dart';
 import 'shader_screen.dart';
-import 'ai_assistant_shader_builder.dart';
 import 'branded_ai_assistant_shader_builder.dart';
 
 void main() {
@@ -120,8 +119,9 @@ final shaders = [
     sourceUrl: 'https://www.shadertoy.com/view/33cGDj',
     author: 'mrange',
     dateAdded: DateTime(2025, 7, 29),
-    builder: const ClearlyBugShaderBuilder(),
+    builder: const CommonShaderBuilder(),
     path: 'clearly-bug-shader',
+    backgroundColor: Colors.black,
   ),
   ShaderInfo(
     name: 'AI Assistant',
@@ -130,7 +130,7 @@ final shaders = [
     sourceUrl: 'https://www.shadertoy.com/view/MXsyzl',
     author: 'Saphirah',
     dateAdded: DateTime(2025, 8, 21),
-    builder: const AiAssistantShaderBuilder(),
+    builder: const CommonShaderBuilder(),
     path: 'ai-assistant',
     padding: EdgeInsets.all(32),
     backgroundColor: Colors.black,
@@ -148,6 +148,18 @@ final shaders = [
     backgroundColor: Colors.black,
     aspectRatio: 1,
   ),
+  ShaderInfo(
+    assetKey: 'shaders/breathing_point.frag',
+    name: 'Breathing Point',
+    description: 'A calming shader that simulates breathing.',
+    sourceUrl: 'https://www.shadertoy.com/view/4dXyWN',
+    author: 'User5518',
+    dateAdded: DateTime(2025, 8, 21),
+    builder: const CommonShaderBuilder(),
+    path: 'breathing-point',
+    backgroundColor: Colors.black,
+    aspectRatio: 1,
+  ),
 ];
 
 // Helper function to create URL-safe shader names

lib/ai_assistant_shader_builder.dart renamed to lib/common_shader_builder.dart

@@ -23,15 +23,18 @@ class NtscShaderBuilder extends CustomShaderBuilder {
     double time,
     Widget? child,
   ) {
-    return AnimatedSampler((image, size, canvas) {
-      if (requiresImageSampler) {
-        shader.setImageSampler(0, image);
-      }
-      canvas.drawRect(
-        Rect.fromLTWH(0, 0, size.width, size.height),
-        Paint()..shader = shader,
-      );
-    }, child: child ?? const SizedBox());
+    return AnimatedSampler(
+      (image, size, canvas) {
+        if (requiresImageSampler) {
+          shader.setImageSampler(0, image);
+        }
+        canvas.drawRect(
+          Rect.fromLTWH(0, 0, size.width, size.height),
+          Paint()..shader = shader,
+        );
+      },
+      child: child ?? const SizedBox(),
+    );
   }
 
   @override

lib/main.dart

@@ -51,3 +51,4 @@ flutter:
     - shaders/clearly_bug_shader.frag
     - shaders/ai_assistant.frag
     - shaders/branded_ai_assistant.frag
+    - shaders/breathing_point.frag

lib/ntsc_shader_builder.dart

@@ -0,0 +1,28 @@
+#version 460 core
+precision mediump float;
+
+#include <flutter/runtime_effect.glsl>
+
+uniform vec2 iResolution;
+uniform float iTime;
+
+out vec4 fragColor;
+
+void main()
+{
+    vec2 fragCoord = FlutterFragCoord().xy;
+	vec2 uv = (fragCoord - .5* iResolution.xy ) / iResolution.y; // Thanks @FabriceNeyret2 for this refactored line.
+    // Old code:
+    // vec2 uv = fragCoord.xy / iResolution.xy; // 0 <> 1.
+	// uv -= .5; // -0.5 <> 0.5
+	// uv.x *= iResolution.x/iResolution.y;
+    
+    float d = length(uv);
+    float ti = iTime;
+    float r = 0.3;
+    
+    float x = (r*(cos(ti*2.0)+1.0)/2.0)+0.001;
+    float c = smoothstep(r, r-x, d);
+    
+	fragColor = vec4(vec3(c), 1.0);
+}