From 21c7f2c23e73f609724bc162e0e204be1d660350 Mon Sep 17 00:00:00 2001
From: Filippo Scognamiglio <flscogna@gmail.com>
Date: Fri, 20 Jun 2014 01:54:14 +0200
Subject: [PATCH] Smooth static noise and fixes

---
 app/ShaderManager.qml |  6 +++---
 app/Terminal.qml      | 25 ++++++++++++++++---------
 2 files changed, 19 insertions(+), 12 deletions(-)

diff --git a/app/ShaderManager.qml b/app/ShaderManager.qml
index 0643a48..9cf0198 100644
--- a/app/ShaderManager.qml
+++ b/app/ShaderManager.qml
@@ -32,7 +32,6 @@ ShaderEffect {
     property real bloom: shadersettings.bloom_strength
 
     property int rasterization: shadersettings.rasterization
-    property real rasterization_strength: 0.5
 
     property real noise_strength: shadersettings.noise_strength
     property real screen_distorsion: shadersettings.screen_distortion
@@ -151,7 +150,8 @@ ShaderEffect {
             "float color = texture2D(source, coords).a;" +
 
             (noise_strength !== 0 ? "
-                color += texture2D(noiseSource, qt_TexCoord0 * 0.25 + fract(time / 100.0)).a * noise * (1.0 - distance * distance * 2.0);" : "") +
+                float noiseVal = texture2D(noiseSource, qt_TexCoord0 + vec2(fract(time / 51.0), fract(time / 237.0))).a;
+                color += noiseVal * noise * (1.0 - distance * 1.3);" : "") +
 
             (glowing_line_strength !== 0 ? "
                 color += randomPass(coords) * glowing_line_strength;" : "") +
@@ -161,7 +161,7 @@ ShaderEffect {
 
             "vec3 finalColor = mix(background_color, font_color, color).rgb;" +
             "finalColor = mix(finalColor * 1.1, vec3(0.0), 1.2 * distance * distance);" +
-            "finalColor *= (texture2D(rasterizationSource, coords).a) / "+rasterization_strength+";" +
+            "finalColor *= texture2D(rasterizationSource, coords).a;" +
 
             (brightness_flickering !== 0 ? "
                 finalColor *= brightness;" : "") +
diff --git a/app/Terminal.qml b/app/Terminal.qml
index 68b4fc9..9c6b9c7 100644
--- a/app/Terminal.qml
+++ b/app/Terminal.qml
@@ -250,16 +250,16 @@ Item{
         (mScanlines == shadersettings.pixel_rasterization ? "
                         coords.x = floor(virtual_resolution.x * coords.x) / virtual_resolution.x;" : "")
         : "") +
-
-        "float color = texture2D(source, coords + delta).r * 256.0;" +
+        "coords = coords + delta;" +
+        "float color = texture2D(source, coords).r * 256.0;" +
         (mBlur !== 0 ?
-        "float blurredSourceColor = texture2D(blurredSource, qt_TexCoord0).a * 256.0;" +
+        "float blurredSourceColor = texture2D(blurredSource, coords).a * 256.0;" +
         "blurredSourceColor = blurredSourceColor - blurredSourceColor * " + (1.0 - motionBlurCoefficient) * fpsAttenuation+ ";" +
         "color = step(1.0, color) * color + step(color, 1.0) * blurredSourceColor;"
         : "") +
 
 
-        "gl_FragColor.a = vec4(floor(color) / 256.0);" +
+        "gl_FragColor.a = floor(color) / 256.0;" +
         "}"
     }
     //////////////////////////////////////////////////////////////////////
@@ -301,7 +301,7 @@ Item{
              varying highp vec2 qt_TexCoord0;
              uniform highp vec2 virtual_resolution;" +
 
-            "highp float rand(vec2 co)
+            "highp float noise(vec2 co)
             {
                 highp float a = 12.9898;
                 highp float b = 78.233;
@@ -311,13 +311,20 @@ Item{
                 return fract(sin(sn) * c);
             }
 
-            float stepNoise(vec2 p){
-                vec2 newP = p * virtual_resolution;
-                return rand(newP);
+            vec2 sw(vec2 p) {return vec2( floor(p.x) , floor(p.y) );}
+            vec2 se(vec2 p) {return vec2( ceil(p.x)  , floor(p.y) );}
+            vec2 nw(vec2 p) {return vec2( floor(p.x) , ceil(p.y)  );}
+            vec2 ne(vec2 p) {return vec2( ceil(p.x)  , ceil(p.y)  );}
+
+            float smoothNoise(vec2 p) {
+                vec2 inter = smoothstep(0., 1., fract(p));
+                float s = mix(noise(sw(p)), noise(se(p)), inter.x);
+                float n = mix(noise(nw(p)), noise(ne(p)), inter.x);
+                return mix(s, n, inter.y);
             }" +
 
         "void main() {" +
-            "gl_FragColor.a = stepNoise(qt_TexCoord0);" +
+            "gl_FragColor.a = smoothNoise(qt_TexCoord0 * virtual_resolution);" +
         "}"
     }
     ShaderEffectSource{