1 files changed, 30 insertions, 3 deletions
diff --git a/evc/src/bin/decode.rs b/evc/src/bin/decode.rs
index af6edc6..44fcbe4 100644
--- a/evc/src/bin/decode.rs
+++ b/evc/src/bin/decode.rs
@@ -5,6 +5,7 @@ use evc::{
     block::{Block, BlockInner},
     frame::Frame,
     header::Header,
+    pixel::Pixel,
     ser::Source,
     view::View,
 };
@@ -12,10 +13,13 @@ use std::io::{BufReader, BufWriter};
 
 #[derive(Parser)]
 #[clap(about, version)]
-pub struct DecodeArgs {}
+pub struct DecodeArgs {
+    #[arg(long)]
+    debug: bool,
+}
 
 fn main() -> anyhow::Result<()> {
-    let _args = DecodeArgs::parse();
+    let args = DecodeArgs::parse();
 
     let mut input = BufReader::new(std::io::stdin());
     let mut output = BufWriter::new(std::io::stdout());
@@ -36,7 +40,14 @@ fn main() -> anyhow::Result<()> {
             prev.view((0, 0), size),
         );
 
-        frame.write(&mut output).context("writing raw frame")?;
+        if args.debug {
+            let mut f2 = frame.clone();
+            draw_debug(&block, f2.view_mut((0, 0), size));
+            f2.write(&mut output).context("writing raw frame")?;
+        } else {
+            frame.write(&mut output).context("writing raw frame")?;
+        }
+
         prev = frame;
     }
     drop(input);
@@ -55,3 +66,19 @@ fn blit_block(block: &Block, mut target: View<&mut Frame>, prev: View<&Frame>) {
         BlockInner::Reference { translation: _ } => target.copy_from(&prev),
     }
 }
+
+fn draw_debug(block: &Block, mut target: View<&mut Frame>) {
+    match &block.inner {
+        BlockInner::Literal(_) => {
+            target.draw_box(Pixel::GREEN);
+        }
+        BlockInner::Split(box [a, b]) => {
+            let [at, bt] = target.split_mut_unsafe();
+            draw_debug(a, at);
+            draw_debug(b, bt);
+        }
+        BlockInner::Reference { translation: _ } => {
+            target.draw_box(Pixel::BLUE);
+        }
+    }
+}