Merge pull request #13 from jhbruhn/fix/combine-color-end-cut-flags

fix: Combine COLOR_END and CUT flags on same stitch for color changes

src/formats/pen/encoder.test.ts

@@ -298,21 +298,15 @@ describe('encodeStitchesToPen', () => {
       idx++;
     }
 
-    // 4. Cut command
+    // 4. COLOR_END + CUT command (combined on same stitch)
-    const cutStitch = decoded[idx];
+    const colorEndCutStitch = decoded[idx];
-    expect(cutStitch.x).toBe(10);
+    expect(colorEndCutStitch.x).toBe(10);
-    expect(cutStitch.y).toBe(0);
+    expect(colorEndCutStitch.y).toBe(0);
-    expect(cutStitch.isCut).toBe(true);
+    expect(colorEndCutStitch.isCut).toBe(true);
+    expect(colorEndCutStitch.isColorEnd).toBe(true);
     idx++;
 
-    // 5. COLOR_END marker (no jump needed since same position)
+    // 5. 8 starting lock stitches for new color
-    const colorEndStitch = decoded[idx];
-    expect(colorEndStitch.x).toBe(10);
-    expect(colorEndStitch.y).toBe(0);
-    expect(colorEndStitch.isColorEnd).toBe(true);
-    idx++;
-
-    // 6. 8 starting lock stitches for new color
     for (let i = 0; i < 8; i++) {
       const lockStitch = decoded[idx];
       expect(lockStitch.x).to.be.closeTo(10, LOCK_STITCH_JUMP_SIZE);
@@ -320,7 +314,7 @@ describe('encodeStitchesToPen', () => {
       idx++;
     }
 
-    // 7. First stitch of new color
+    // 6. First stitch of new color
     expect(decoded[idx].x).toBe(10);
     expect(decoded[idx].y).toBe(0);
     idx++;
@@ -353,9 +347,11 @@ describe('encodeStitchesToPen', () => {
       idx++;
     }
 
-    // 2. Cut command at (10, 0)
+    // 2. COLOR_END + CUT command at (10, 0) - combined on same stitch
-    expect(decoded[idx].isCut).toBe(true);
     expect(decoded[idx].x).toBe(10);
+    expect(decoded[idx].y).toBe(0);
+    expect(decoded[idx].isCut).toBe(true);
+    expect(decoded[idx].isColorEnd).toBe(true);
     idx++;
 
     // 3. Jump to new position (30, 10)
@@ -364,20 +360,14 @@ describe('encodeStitchesToPen', () => {
     expect(decoded[idx].isFeed).toBe(true);
     idx++;
 
-    // 4. COLOR_END marker at (30, 10)
+    // 4. 8 starting lock stitches at (30, 10)
-    expect(decoded[idx].x).toBe(30);
-    expect(decoded[idx].y).toBe(10);
-    expect(decoded[idx].isColorEnd).toBe(true);
-    idx++;
-
-    // 5. 8 starting lock stitches at (30, 10)
     for (let i = 0; i < 8; i++) {
       expect(decoded[idx].x).to.be.closeTo(30, LOCK_STITCH_JUMP_SIZE);
       expect(decoded[idx].y).to.be.closeTo(10, LOCK_STITCH_JUMP_SIZE);
       idx++;
     }
 
-    // 6. Continue with new color stitches
+    // 5. Continue with new color stitches
     expect(decoded[idx].x).toBe(30);
     expect(decoded[idx].y).toBe(10);
   });
@@ -421,10 +411,11 @@ describe('encodeStitchesToPen', () => {
       idx++;
     }
 
-    // 4. Cut command at (10, 0)
+    // 4. COLOR_END + CUT command at (10, 0) - combined on same stitch
     expect(decoded[idx].x).toBe(10);
     expect(decoded[idx].y).toBe(0);
     expect(decoded[idx].isCut).toBe(true);
+    expect(decoded[idx].isColorEnd).toBe(true);
     idx++;
 
     // 5. Jump to new location (50, 20) - extracted from the MOVE stitch
@@ -433,26 +424,20 @@ describe('encodeStitchesToPen', () => {
     expect(decoded[idx].isFeed).toBe(true);
     idx++;
 
-    // 6. COLOR_END marker at (50, 20)
+    // 6. 8 starting lock stitches at (50, 20)
-    expect(decoded[idx].x).toBe(50);
-    expect(decoded[idx].y).toBe(20);
-    expect(decoded[idx].isColorEnd).toBe(true);
-    idx++;
-
-    // 7. 8 starting lock stitches at (50, 20)
     for (let i = 0; i < 8; i++) {
       expect(decoded[idx].x).to.be.closeTo(50, LOCK_STITCH_JUMP_SIZE);
       expect(decoded[idx].y).to.be.closeTo(20, LOCK_STITCH_JUMP_SIZE);
       idx++;
     }
 
-    // 8. First actual stitch of new color at (50, 20)
+    // 7. First actual stitch of new color at (50, 20)
     expect(decoded[idx].x).toBe(50);
     expect(decoded[idx].y).toBe(20);
     expect(decoded[idx].isFeed).toBe(false);
     idx++;
 
-    // 9. Last stitch with DATA_END
+    // 8. Last stitch with DATA_END
     expect(decoded[idx].x).toBe(60);
     expect(decoded[idx].y).toBe(20);
     expect(decoded[idx].isDataEnd).toBe(true);
@@ -666,7 +651,7 @@ describe('encodeStitchesToPen', () => {
 
     const result = encodeStitchesToPen(stitches);
     const decoded = decodeAllPenStitches(result.penBytes);
-    console.log(decoded);
+
     // Expected sequence:
     // 0. Feed move to proper location (should always happen here)
     // 1. 8 starting lock stitches at (10, 20)

src/formats/pen/encoder.ts

@@ -17,7 +17,7 @@ const PEN_DATA_END = 0x05;  // Last stitch of entire pattern
 const FEED_LENGTH = 50; // Long jump threshold requiring lock stitches and cut
 const TARGET_LENGTH = 8.0;  // Target accumulated length for lock stitch direction
 const MAX_POINTS = 5;        // Maximum points to accumulate for lock stitch direction
-export const LOCK_STITCH_JUMP_SIZE = 4.0;
+export const LOCK_STITCH_JUMP_SIZE = 2.0;
 const LOCK_STITCH_SCALE = LOCK_STITCH_JUMP_SIZE / 8.0; // Scale the magnitude-8 vector down to 4
 
 export interface StitchData {
@@ -286,7 +286,7 @@ export function encodeStitchesToPen(stitches: number[][]): PenEncodingResult {
       penStitches.push(...generateLockStitches(absX, absY, startDir.dirX, startDir.dirY));
     }
 
-    // Handle color change: finishing lock, cut, jump, COLOR_END, starting lock
+    // Handle color change: finishing lock, COLOR_END+CUT, jump, starting lock
     if (isColorChange) {
       const nextStitchCmd = nextStitch[2];
       const nextStitchX = Math.round(nextStitch[0]);
@@ -299,17 +299,26 @@ export function encodeStitchesToPen(stitches: number[][]): PenEncodingResult {
       const finishDir = calculateLockDirection(stitches, i, true);
       penStitches.push(...generateLockStitches(absX, absY, finishDir.dirX, finishDir.dirY));
 
-      // Step 2: Add cut command at current position
+      // Step 2: Add COLOR_END + CUT command at CURRENT position (same stitch!)
-      const cutXEncoded = (absX << 3) & 0xffff;
+      // This is where the machine pauses and waits for the user to change thread color
-      const cutYEncoded = ((absY << 3) & 0xffff) | PEN_CUT_DATA;
+      // IMPORTANT: COLOR_END and CUT must be on the SAME stitch, not separate stitches
+      let colorEndCutXEncoded = (absX << 3) & 0xffff;
+      let colorEndCutYEncoded = (absY << 3) & 0xffff;
+
+      // Add COLOR_END flag to X coordinate and CUT flag to Y coordinate
+      colorEndCutXEncoded = (colorEndCutXEncoded & 0xfff8) | PEN_COLOR_END;
+      colorEndCutYEncoded |= PEN_CUT_DATA;
 
       penStitches.push(
-        cutXEncoded & 0xff,
+        colorEndCutXEncoded & 0xff,
-        (cutXEncoded >> 8) & 0xff,
+        (colorEndCutXEncoded >> 8) & 0xff,
-        cutYEncoded & 0xff,
+        colorEndCutYEncoded & 0xff,
-        (cutYEncoded >> 8) & 0xff
+        (colorEndCutYEncoded >> 8) & 0xff
       );
 
+      // Machine pauses here for color change
+      // After user changes color, the following stitches execute with the new color
+
       // Step 3: If next stitch is a JUMP, encode it and skip it in the loop
       // Otherwise, add a jump ourselves if positions differ
       const jumpToX = nextStitchX;
@@ -334,22 +343,7 @@ export function encodeStitchesToPen(stitches: number[][]): PenEncodingResult {
         );
       }
 
-      // Step 4: Add COLOR_END marker at NEW position
+      // Step 4: Add starting lock stitches at the new position
-      // This is where the machine pauses and waits for the user to change thread color
-      let colorEndXEncoded = (jumpToX << 3) & 0xffff;
-      const colorEndYEncoded = (jumpToY << 3) & 0xffff;
-
-      // Add COLOR_END flag to X coordinate
-      colorEndXEncoded = (colorEndXEncoded & 0xfff8) | PEN_COLOR_END;
-
-      penStitches.push(
-        colorEndXEncoded & 0xff,
-        (colorEndXEncoded >> 8) & 0xff,
-        colorEndYEncoded & 0xff,
-        (colorEndYEncoded >> 8) & 0xff
-      );
-
-      // Step 5: Add starting lock stitches at the new position
       // Loop A: Jump/Entry Vector - Look FORWARD at upcoming stitches in new color
       // This hides the knot under the stitches we're about to make
       const nextStitchIdx = nextIsJump ? i + 2 : i + 1;