minor bug fix and refactor

shaders/blur.comp

@@ -1,25 +1,22 @@
 #version 450
+
 layout(local_size_x = 16, local_size_y = 16) in;
-layout(binding = 0) uniform sampler2D srcImage;
-layout(rgba8, binding = 1) uniform image2D dstImage;
+layout(set = 0, binding = 0) uniform sampler2D inputTex;
+layout(set = 0, binding = 1, rgba8) uniform writeonly image2D outputTex;
 
 void main() {
     ivec2 gid = ivec2(gl_GlobalInvocationID.xy);
-    ivec2 size = imageSize(dstImage);
-    if (gid.x >= size.x || gid.y >= size.y) return;
-
-    vec2 texelSize = 1.0 / vec2(size);
+    vec2 size = vec2(imageSize(outputTex));
+    vec2 texelSize = 1.0 / size;
     vec4 color = vec4(0.0);
-    int radius = 5;
-    int samples = 0;
-
-    for (int dx = -radius; dx <= radius; dx++) {
-        for (int dy = -radius; dy <= radius; dy++) {
-            vec2 offset = vec2(dx, dy) * texelSize;
-            color += texture(srcImage, (vec2(gid) + 0.5) / vec2(size) + offset);
-            samples++;
+    int count = 0;
+    for (int dx = -7; dx <= 7; dx++) {
+        for (int dy = -7; dy <= 7; dy++) {
+            vec2 offset = vec2(float(dx), float(dy)) * texelSize;
+            color += texture(inputTex, (vec2(gid) + 0.5) / size + offset);
+            count++;
         }
     }
-    imageStore(dstImage, gid, color / float(samples));
+    color /= float(count);
+    imageStore(outputTex, gid, color);
 }
-

src/main.rs

@@ -65,7 +65,18 @@ fn parse_args(args: &[String]) -> (String, String, f32, f32) {
     let wall = args.iter().position(|a| a == "--wall" || a == "-w")
         .and_then(|i| args.get(i + 1).cloned())
         .or_else(|| {
-            args.iter().skip(2).find(|a| !a.starts_with('-')).cloned()
+            args.iter().skip(2).scan(false, |skip, a| {
+                if *skip {
+                    *skip = false;
+                    Some(None)
+                } else if a.starts_with('-') {
+                    *skip = true;
+                    Some(None)
+                } else {
+                    Some(Some(a.clone()))
+                }
+            })
+            .flatten().last()
         })
         .unwrap_or_else(|| {
             eprintln!("Missing wallpaper (use --wall <path> or bare path)");