From 43c53555d9bf3db9bff55d96e5d4cdb0b876b734 Mon Sep 17 00:00:00 2001
From: Xiretza <xiretza@xiretza.xyz>
Date: Fri, 17 Jun 2022 21:30:30 +0200
Subject: [PATCH] feat: allow smaller images

---
 src/strandifier.rs | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/src/strandifier.rs b/src/strandifier.rs
index 59e90ea..80d256c 100644
--- a/src/strandifier.rs
+++ b/src/strandifier.rs
@@ -23,6 +23,9 @@ pub struct Strandifier<'a> {
     pixels_remaining: u32,
     next_x: u32,
     next_y: u32,
+
+    offset_x: u32,
+    offset_y: u32,
 }
 
 impl<'a> Strandifier<'a> {
@@ -41,7 +44,7 @@ impl<'a> Strandifier<'a> {
         image: &'a RgbImage,
         strand_num: u32,
     ) -> Result<Self, StrandifierError> {
-        if layout.width_px() != image.width() || layout.height_px() != image.height() {
+        if layout.width_px() < image.width() || layout.height_px() < image.height() {
             return Err(StrandifierError::WrongDimensions);
         }
 
@@ -55,6 +58,9 @@ impl<'a> Strandifier<'a> {
         let first_x = panel_x * layout.gang_len;
         let first_y = panel_y * layout.num_gangs;
 
+        let offset_x = (layout.width_px() - image.width()) / 2;
+        let offset_y = (layout.height_px() - image.height()) / 2;
+
         Ok(Self {
             layout,
             image,
@@ -62,6 +68,9 @@ impl<'a> Strandifier<'a> {
             pixels_remaining: layout.strand_len(),
             next_x: first_x,
             next_y: first_y,
+
+            offset_x,
+            offset_y,
         })
     }
 }
@@ -98,7 +107,7 @@ impl<'a> Iterator for Strandifier<'a> {
         }
         self.pixels_remaining -= 1;
 
-        Some(*self.image.get_pixel(x, y))
+        Some(*self.image.get_pixel(x + self.offset_x, y + self.offset_y))
     }
 
     fn size_hint(&self) -> (usize, Option<usize>) {