From 5461cb7f9300aeb03dfb7443d341759fa5e085ca Mon Sep 17 00:00:00 2001
From: tittu <prasanthrangan@rediffmail.com>
Date: Fri, 12 Jun 2026 23:46:20 +0530
Subject: [PATCH] adding anchoring feature

---
 src/main.rs       | 22 +++++++++++++++++++++-
 src/vulkan.rs     | 14 +++++++++-----
 src/wallbashed.rs | 15 +++++++++++++--
 3 files changed, 43 insertions(+), 8 deletions(-)

diff --git a/src/main.rs b/src/main.rs
index cc398ea..e0e56a8 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -50,6 +50,25 @@ fn send_command(cmd: &str) -> Result<(), Box<dyn std::error::Error>> {
     Ok(())
 }
 
+fn parse_anchor(args: &[String]) -> (f32, f32) {
+    let i = args.iter().position(|a| a == "--anchor" || a == "-a");
+    let num = i
+        .and_then(|i| args.get(i + 1))
+        .and_then(|val| val.parse::<u8>().ok());
+    match num {
+        Some(1) => (0.0, 0.0),
+        Some(2) => (0.5, 0.0),
+        Some(3) => (1.0, 0.0),
+        Some(4) => (0.0, 0.5),
+        Some(5) => (0.5, 0.5),
+        Some(6) => (1.0, 0.5),
+        Some(7) => (0.0, 1.0),
+        Some(8) => (0.5, 1.0),
+        Some(9) => (1.0, 1.0),
+        _ => (0.5, 0.5),
+    }
+}
+
 
 // --------------------------------------------------------------------- / main
 
@@ -90,7 +109,8 @@ fn main() {
                     return;
                 }
             }
-            let cmd = format!("set {}", args[2]);
+            let (anchor_h, anchor_v) = parse_anchor(&args);
+            let cmd = format!("set {} {} {}", args[2], anchor_h, anchor_v);
             if let Err(e) = send_command(&cmd) {
                 eprintln!("Failed to set wallpaper {}. Is the daemon running?", e);
             }
diff --git a/src/vulkan.rs b/src/vulkan.rs
index 6d0b056..5ee3d10 100644
--- a/src/vulkan.rs
+++ b/src/vulkan.rs
@@ -523,6 +523,8 @@ pub fn draw_wallpaper(
     texture_height: u32,
     swapchain_extent_width: u32,
     swapchain_extent_height: u32,
+    anchor_x: f32,
+    anchor_y: f32,
 ) -> Result<(), Box<dyn std::error::Error>> {
 
     // acquire swapchain image
@@ -594,18 +596,20 @@ pub fn draw_wallpaper(
         );
     }
 
-    // preserve aspect ratios and fill screen
+    // preserve aspect ratios and fill screen (anchored crop)
     let src_aspect = texture_width as f64 / texture_height as f64;
     let dst_aspect = swapchain_extent_width as f64 / swapchain_extent_height as f64;
     let (src_x, src_y, src_w, src_h) = if src_aspect > dst_aspect {
-        // Image is wider than screen → crop left/right
+        // Image is wider → crop left/right, horizontal anchor controls which side is kept
         let new_width = (texture_height as f64 * dst_aspect) as u32;
-        let x = (texture_width - new_width) / 2;
+        let max_x = (texture_width - new_width) as f32;
+        let x = (max_x * anchor_x) as u32;
         (x, 0, new_width, texture_height)
     } else {
-        // Image is taller than screen → crop top/bottom
+        // Image is taller → crop top/bottom, vertical anchor controls which part is kept
         let new_height = (texture_width as f64 / dst_aspect) as u32;
-        let y = (texture_height - new_height) / 2;
+        let max_y = (texture_height - new_height) as f32;
+        let y = (max_y * anchor_y) as u32;
         (0, y, texture_width, new_height)
     };
 
diff --git a/src/wallbashed.rs b/src/wallbashed.rs
index fcd83a0..84b4fff 100644
--- a/src/wallbashed.rs
+++ b/src/wallbashed.rs
@@ -62,6 +62,8 @@ fn set_wallpaper(
     layer_width: u32,
     layer_height: u32,
     wallpaper: &mut Option<vulkan::VulkanTexture>,
+    anchor_x: f32,
+    anchor_y: f32,
 ) -> Result<(), Box<dyn std::error::Error>> {
 
     // load the wallpaper
@@ -105,6 +107,8 @@ fn set_wallpaper(
         img.height(),
         layer_width,
         layer_height,
+        anchor_x,
+        anchor_y,
     )?;
 
     Ok(())
@@ -157,12 +161,15 @@ pub fn run(socket_path: &str) -> Result<(), Box<dyn std::error::Error>> {
                 println!("[wallbash] stopping daemon.");
                 running = false;
             } else if raw.starts_with("set ") {
-                let path = raw[4..].trim().to_string();
+                let args: Vec<&str> = raw[4..].trim().split_whitespace().collect();
+                let path = args[..args.len()-2].join(" ");
+                let anchor_x: f32 = args[args.len()-2].parse().unwrap_or(0.5);
+                let anchor_y: f32 = args[args.len()-1].parse().unwrap_or(0.5);
                 let resolved = std::fs::canonicalize(&path)
                     .map(|p| p.to_string_lossy().to_string())
                     .unwrap_or(path);
 
-                println!("[wallbash] loading {}", resolved);
+                println!("[wallbash] loading {} (anchor {}/{})", resolved, anchor_x, anchor_y);
                 match set_wallpaper(
                     &resolved,
                     &vk_core,
@@ -170,6 +177,8 @@ pub fn run(socket_path: &str) -> Result<(), Box<dyn std::error::Error>> {
                     wl_core.state.layer_width,
                     wl_core.state.layer_height,
                     &mut wallpaper,
+                    anchor_x,
+                    anchor_y,
                 ) {
                     Ok(()) => println!("[wallbash] wallpaper set."),
                     Err(e) if e.to_string().contains("out of date") => {
@@ -210,6 +219,8 @@ pub fn run(socket_path: &str) -> Result<(), Box<dyn std::error::Error>> {
                             wl_core.state.layer_width,
                             wl_core.state.layer_height,
                             &mut wallpaper,
+                            anchor_x,
+                            anchor_y,
                         ) {
                             eprintln!("[wallbash] error after swapchain recreation {}", e3);
                         }