🎉 Add initial matrix shader

2021-12-22 21:34:03 +01:00
parent 75b803d523
commit 547db3a2b8
6 changed files with 432 additions and 46 deletions
@@ -0,0 +1,120 @@
+//////////////////////////////////////////////////////////////////////////////////////////
+//          )                                                   (                       //
+//       ( /(   (  (               )    (       (  (  (         )\ )    (  (            //
+//       )\()) ))\ )(   (         (     )\ )    )\))( )\  (    (()/( (  )\))(  (        //
+//      ((_)\ /((_|()\  )\ )      )\  '(()/(   ((_)()((_) )\ )  ((_)))\((_)()\ )\       //
+//      | |(_|_))( ((_)_(_/(    _((_))  )(_))  _(()((_|_)_(_/(  _| |((_)(()((_|(_)      //
+//      | '_ \ || | '_| ' \))  | '  \()| || |  \ V  V / | ' \)) _` / _ \ V  V (_-<      //
+//      |_.__/\_,_|_| |_||_|   |_|_|_|  \_, |   \_/\_/|_|_||_|\__,_\___/\_/\_//__/      //
+//                                 |__/                                                 //
+//                       Copyright (c) 2021 Simon Schneegans                            //
+//          Released under the GPLv3 or later. See LICENSE file for details.            //
+//////////////////////////////////////////////////////////////////////////////////////////
+
+'use strict';
+
+const {Clutter, GObject, GdkPixbuf, Cogl} = imports.gi;
+
+const ExtensionUtils = imports.misc.extensionUtils;
+const Me             = imports.misc.extensionUtils.getCurrentExtension();
+const shaderSnippets = Me.imports.src.extension.shaderSnippets;
+
+//////////////////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////////////////////
+
+var MatrixShader = GObject.registerClass({Properties: {}, Signals: {}},
+                                         class MatrixShader extends Clutter.ShaderEffect {
+  _init(settings) {
+    super._init({shader_type: Clutter.ShaderType.FRAGMENT_SHADER});
+
+    const fontData    = GdkPixbuf.Pixbuf.new_from_resource('/img/matrixFont.png');
+    this._fontTexture = new Clutter.Image();
+    this._fontTexture.set_data(
+        fontData.get_pixels(),
+        fontData.has_alpha ? Cogl.PixelFormat.RGBA_8888 : Cogl.PixelFormat.RGB_888,
+        fontData.width, fontData.height, fontData.rowstride);
+
+    // This is roughly based on https://www.shadertoy.com/view/ldccW4 (CC-BY-NC-SA).
+    this.set_shader_source(`
+
+      // Inject some common shader snippets.
+      ${shaderSnippets.standardUniforms()}
+      ${shaderSnippets.noise()}
+
+      uniform sampler2D uFontTexture;
+
+      // These may be configurable in the future.
+      const float EDGE_FADE  = 30;
+      const float FADE_WIDTH = 50;
+      const float TRAIL_LENGTH  = 0.2;
+      const float FINAL_FADE_START_TIME  = 0.8;
+      const float LETTER_TILES  = 16.0;
+      const float LETTER_SIZE  = 16.0;
+      const float BRIGHTNESS_BOOST  = 2;
+      const float RANDOMNESS  = 1.0;
+
+      float getText(vec2 fragCoord) {
+        vec2 coords = fragCoord * vec2(uSizeX, uSizeY);
+        vec2 uv = mod(coords.xy, LETTER_SIZE)/LETTER_SIZE;
+        vec2 block = coords/LETTER_SIZE - uv;
+
+        // scale the letters up a bit
+        uv = uv*.8+.1;
+        
+        // bring back into 0-1 range 
+        uv += floor(rand2(block/512 + uTime*.0000001)*LETTER_TILES);
+        uv /= LETTER_TILES; 
+        
+        // flip letters horizontally
+        uv.x = -uv.x+1.0;
+        return texture2D(uFontTexture, uv).r;
+      }
+
+      vec2 getRain(vec2 fragCoord) {
+        vec2 coords = fragCoord * vec2(uSizeX, uSizeY);
+        coords.x -= mod(coords.x, LETTER_SIZE);
+
+        float delay = abs(sin(coords.x * 3.0)) * mix(0.0, 1.0, RANDOMNESS);
+        float speed  = cos(coords.x * 7.0) * mix(0.0, 0.3, RANDOMNESS) + 1.5;
+
+        float distToDrop = (uProgress*2-delay)*speed - fragCoord.y;
+        return vec2(distToDrop >= 0 ? exp(-distToDrop/TRAIL_LENGTH) : 0,
+                    clamp(uSizeY*distToDrop, 0, FADE_WIDTH) / FADE_WIDTH);
+      }
+
+      void main() {
+
+        vec3 color = vec3(0.1,1,0.35);
+
+        // Get a cool matrix effect.
+        vec2  rain = getRain(cogl_tex_coord_in[0].st);
+        float text = getText(cogl_tex_coord_in[0].st);
+
+        // Get the window texture and fade it according to the effect mask.
+        float windowAlpha = 1 - rain.y;
+        cogl_color_out = texture2D(uTexture, cogl_tex_coord_in[0].st) * windowAlpha;
+
+        float finalFade = 1-clamp((uProgress-FINAL_FADE_START_TIME)/(1-FINAL_FADE_START_TIME), 0, 1);
+        float textAlpha = finalFade * rain.x * BRIGHTNESS_BOOST;
+
+
+        // Fade at window borders.
+        vec2 pos = cogl_tex_coord_in[0].st * vec2(uSizeX, uSizeY);
+        textAlpha *= clamp(pos.x / EDGE_FADE, 0, 1);
+        textAlpha *= clamp(pos.y / EDGE_FADE, 0, 1);
+        textAlpha *= clamp((uSizeX - pos.x) / EDGE_FADE, 0, 1);
+        textAlpha *= clamp((uSizeY - pos.y) / EDGE_FADE, 0, 1);
+
+        // Add the fire to the window.
+        cogl_color_out.rgb += color * textAlpha * text;
+      }
+    `);
+  };
+
+  vfunc_paint_target(node, paint_context) {
+    const pipeline = this.get_pipeline();
+    pipeline.set_layer_texture(1, this._fontTexture.get_texture());
+    this.set_uniform_value('uFontTexture', 1);
+    super.vfunc_paint_target(node, paint_context);
+  }
+});