[libadwaita/wip/exalm/shaders: 3/4] glsl: Fix syntax

[Alexander Mikhaylenko <alexm src gnome org>]

commit d71ca345c1117a93e1a658b44919f82d09827fe4
Author: Alexander Mikhaylenko <alexm gnome org>
Date:   Thu Jul 28 15:05:34 2022 +0400

    glsl: Fix syntax
    
    Looks like it can fail to compile depending on the GL version.

 src/glsl/fade.glsl | 8 ++++----
 src/glsl/mask.glsl | 2 +-
 2 files changed, 5 insertions(+), 5 deletions(-)
---
diff --git a/src/glsl/fade.glsl b/src/glsl/fade.glsl
index 0953d5b5..01338ebd 100644
--- a/src/glsl/fade.glsl
+++ b/src/glsl/fade.glsl
@@ -18,10 +18,10 @@ mainImage (out vec4 fragColor,
   fragColor = GskTexture (u_texture1, uv);
 
   progress = fragCoord.x - offsetLeft;
-  progress = min (max (progress / widthLeft, 0), 1);
-  fragColor *= (1 + strengthLeft * (progress - 1));
+  progress = min (max (progress / widthLeft, 0.0), 1.0);
+  fragColor *= (1.0 + strengthLeft * (progress - 1.0));
 
   progress = resolution.x - offsetRight - fragCoord.x;
-  progress = min (max (progress / widthRight, 0), 1);
-  fragColor *= (1 + strengthRight * (progress - 1));
+  progress = min (max (progress / widthRight, 0.0), 1.0);
+  fragColor *= (1.0 + strengthRight * (progress - 1.0));
 }
diff --git a/src/glsl/mask.glsl b/src/glsl/mask.glsl
index 3b56ce9c..602dd508 100644
--- a/src/glsl/mask.glsl
+++ b/src/glsl/mask.glsl
@@ -10,5 +10,5 @@ mainImage (out vec4 fragColor,
   vec4 source = GskTexture (u_texture1, uv);
   vec4 mask = GskTexture (u_texture2, uv);
 
-  fragColor = source * (1 - mask.w);
+  fragColor = source * (1.0 - mask.a);
 }