Merge pull request #222 from yongyi781/en-passant-fix

kevinjosethomas · web-flow · commit c5c5f0b37910 · 2025-12-05T15:02:16.000-05:00
Fix en passant bug
diff --git a/src/lib/engine/tensor.ts b/src/lib/engine/tensor.ts
@@ -83,8 +83,7 @@ function boardToTensor(fen: string): Float32Array {
   if (enPassantTarget !== '-') {
     const file = enPassantTarget.charCodeAt(0) - 'a'.charCodeAt(0)
     const rank = parseInt(enPassantTarget[1], 10) - 1 // Adjust rank indexing
-    const row = 7 - rank // Invert rank to match tensor indexing
-    const index = epChannel + row * 8 + file
+    const index = epChannel + rank * 8 + file
     tensor[index] = 1.0
   }
 

Original file line number	Diff line number	Diff line change
`@@ -83,8 +83,7 @@ function boardToTensor(fen: string): Float32Array {`
`83`	`83`	`if (enPassantTarget !== '-') {`
`84`	`84`	`const file = enPassantTarget.charCodeAt(0) - 'a'.charCodeAt(0)`
`85`	`85`	`const rank = parseInt(enPassantTarget[1], 10) - 1 // Adjust rank indexing`
`86`		`- const row = 7 - rank // Invert rank to match tensor indexing`
`87`		`- const index = epChannel + row * 8 + file`
	`86`	`+ const index = epChannel + rank * 8 + file`
`88`	`87`	`tensor[index] = 1.0`
`89`	`88`	`}`
`90`	`89`