From dd3bc7d30464a7ae0dbe0bf06a767787ed3edd86 Mon Sep 17 00:00:00 2001
From: finscn <finscn@gmail.com>
Date: Thu, 25 Jan 2018 01:44:31 +0800
Subject: [PATCH] fix the bug about gl_FragColor on iOS

---
 filters/bulge-pinch/src/bulgePinch.frag  | 6 ++++--
 filters/godray/src/gorday.frag           | 4 ++--
 filters/motion-blur/src/motion-blur.frag | 7 ++++---
 filters/radial-blur/src/radial-blur.frag | 9 ++++++---
 filters/shockwave/src/shockwave.frag     | 8 +++++---
 filters/tilt-shift/src/tilt-shift.frag   | 6 ++++--
 filters/zoom-blur/src/zoom-blur.frag     | 6 +++---
 7 files changed, 28 insertions(+), 18 deletions(-)

diff --git a/filters/bulge-pinch/src/bulgePinch.frag b/filters/bulge-pinch/src/bulgePinch.frag
index ec0bde774..c55463dc6 100644
--- a/filters/bulge-pinch/src/bulgePinch.frag
+++ b/filters/bulge-pinch/src/bulgePinch.frag
@@ -24,8 +24,10 @@ void main()
     coord += center * dimensions.xy;
     coord /= filterArea.xy;
     vec2 clampedCoord = clamp(coord, filterClamp.xy, filterClamp.zw);
-    gl_FragColor = texture2D(uSampler, clampedCoord);
+    vec4 color = texture2D(uSampler, clampedCoord);
     if (coord != clampedCoord) {
-        gl_FragColor *= max(0.0, 1.0 - length(coord - clampedCoord));
+        color *= max(0.0, 1.0 - length(coord - clampedCoord));
     }
+
+    gl_FragColor = color;
 }
diff --git a/filters/godray/src/gorday.frag b/filters/godray/src/gorday.frag
index f24b40855..64e3ab41b 100644
--- a/filters/godray/src/gorday.frag
+++ b/filters/godray/src/gorday.frag
@@ -14,7 +14,6 @@ uniform float time;
 ${perlin}
 
 void main(void) {
-    gl_FragColor = texture2D(uSampler, vTextureCoord);
     vec2 coord = vTextureCoord * filterArea.xy / dimensions.xy;
 
     float d;
@@ -37,5 +36,6 @@ void main(void) {
     //fade vertically.
     vec4 mist = vec4(noise, noise, noise, 1.0) * (1.0 - coord.y);
     mist.a = 1.0;
-    gl_FragColor += mist;
+
+    gl_FragColor = texture2D(uSampler, vTextureCoord) + mist;
 }
diff --git a/filters/motion-blur/src/motion-blur.frag b/filters/motion-blur/src/motion-blur.frag
index 7021d91d9..c357d7c6e 100644
--- a/filters/motion-blur/src/motion-blur.frag
+++ b/filters/motion-blur/src/motion-blur.frag
@@ -21,10 +21,11 @@ float offset = -uOffset / length(uVelocity) - 0.5;
 
 void main(void)
 {
-    gl_FragColor = texture2D(uSampler, vTextureCoord);
+    vec4 color = texture2D(uSampler, vTextureCoord);
 
     if (uKernelSize == 0)
     {
+        gl_FragColor = color;
         return;
     }
 
@@ -33,7 +34,7 @@ void main(void)
             break;
         }
         vec2 bias = velocity * (float(i) / k + offset);
-        gl_FragColor += texture2D(uSampler, vTextureCoord + bias);
+        color += texture2D(uSampler, vTextureCoord + bias);
     }
-    gl_FragColor /= kernelSize;
+    gl_FragColor = color / kernelSize;
 }
diff --git a/filters/radial-blur/src/radial-blur.frag b/filters/radial-blur/src/radial-blur.frag
index bee721b55..97eefeb88 100644
--- a/filters/radial-blur/src/radial-blur.frag
+++ b/filters/radial-blur/src/radial-blur.frag
@@ -26,10 +26,11 @@ float radius = uRadius / filterArea.x - gradient * 0.5;
 
 void main(void)
 {
-    gl_FragColor = texture2D(uSampler, vTextureCoord);
+    vec4 color = texture2D(uSampler, vTextureCoord);
 
     if (uKernelSize == 0)
     {
+        gl_FragColor = color;
         return;
     }
 
@@ -45,6 +46,7 @@ void main(void)
         float gap = gradient;
         float scale = 1.0 - abs(delta / gap);
         if (scale <= 0.0) {
+            gl_FragColor = color;
             return;
         }
         radianStep = uRadian * scale / k;
@@ -72,7 +74,8 @@ void main(void)
         // switch to pre-multiplied alpha to correctly blur transparent images
         // sample.rgb *= sample.a;
 
-        gl_FragColor += sample;
+        color += sample;
     }
-    gl_FragColor /= kernelSize;
+
+    gl_FragColor = color / kernelSize;
 }
diff --git a/filters/shockwave/src/shockwave.frag b/filters/shockwave/src/shockwave.frag
index 572fe87f9..ec6076342 100644
--- a/filters/shockwave/src/shockwave.frag
+++ b/filters/shockwave/src/shockwave.frag
@@ -55,13 +55,15 @@ void main()
     // Do clamp :
     vec2 coord = vTextureCoord + offset;
     vec2 clampedCoord = clamp(coord, filterClamp.xy, filterClamp.zw);
-    gl_FragColor = texture2D(uSampler, clampedCoord);
+    vec4 color = texture2D(uSampler, clampedCoord);
     if (coord != clampedCoord) {
-        gl_FragColor *= max(0.0, 1.0 - length(coord - clampedCoord));
+        color *= max(0.0, 1.0 - length(coord - clampedCoord));
     }
 
     // No clamp :
     // gl_FragColor = texture2D(uSampler, vTextureCoord + offset);
 
-    gl_FragColor.rgb *= 1.0 + (brightness - 1.0) * p * fade;
+    color.rgb *= 1.0 + (brightness - 1.0) * p * fade;
+
+    gl_FragColor = color;
 }
diff --git a/filters/tilt-shift/src/tilt-shift.frag b/filters/tilt-shift/src/tilt-shift.frag
index fff2be057..e8894a04f 100644
--- a/filters/tilt-shift/src/tilt-shift.frag
+++ b/filters/tilt-shift/src/tilt-shift.frag
@@ -32,6 +32,8 @@ void main(void)
         total += weight;
     }
 
-    gl_FragColor = color / total;
-    gl_FragColor.rgb /= gl_FragColor.a + 0.00001;
+    color /= total;
+    color.rgb /= color.a + 0.00001;
+
+    gl_FragColor = color;
 }
diff --git a/filters/zoom-blur/src/zoom-blur.frag b/filters/zoom-blur/src/zoom-blur.frag
index c22fce160..3ef53998d 100644
--- a/filters/zoom-blur/src/zoom-blur.frag
+++ b/filters/zoom-blur/src/zoom-blur.frag
@@ -76,9 +76,9 @@ void main() {
         }
     }
 
-    gl_FragColor = color / total;
-
+    color /= total;
     // switch back from pre-multiplied alpha
-    gl_FragColor.rgb /= gl_FragColor.a + 0.00001;
+    color.rgb /= color.a + 0.00001;
 
+    gl_FragColor = color;
 }