From 84aa70f532e29846f289fe7cdfad6e3e56f0cebe Mon Sep 17 00:00:00 2001
From: gramps <gramps@llamachile.shop>
Date: Tue, 8 Sep 2026 11:18:12 -0700
Subject: [PATCH] =?UTF-8?q?docs:=20MyMistakes.md=20=E2=80=94=20take-22=20f?=
 =?UTF-8?q?ull=20fix=20for=20widget=20scale/position=20+=20transparency?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
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---
 MyMistakes.md | 27 ++++++++++++++++++---------
 1 file changed, 18 insertions(+), 9 deletions(-)

diff --git a/MyMistakes.md b/MyMistakes.md
index 4e185bd..03d1244 100644
--- a/MyMistakes.md
+++ b/MyMistakes.md
@@ -15,7 +15,7 @@
 
 ## 🔬 Recipes registry
 
-### ⚠ SPIN GUARD TRIGGERED → RESOLVED (take-21) — web overlay composites dark over the webcam
+### ⚠ SPIN GUARD TRIGGERED → RESOLVED (take-21, 22) — web overlay transparency + scale
 
 **Take-19 (`0f441d8`): FAILED.** Attempted to feed the compositor the FULL canvas instead of the
 alpha crop. User verdict: "didn't work at all — broke additional crap." Reverted (`1295e0e`).
@@ -23,14 +23,23 @@ The crop→UniformToFill zoom insight was RIGHT, but the commit ALSO introduced
 full-canvas buffer ring) alongside the fix — the ring reuse poisoned the paste cache (array identity
 collisions via the Epoch mechanism), causing additional breakage beyond the transparency issue.
 
-**Take-21 (`e002847`): FIXED.** Root cause confirmed: `bccdb48` introduced `FindContentBounds`
-alpha cropping; the CROP was fed to the compositor (`session.LatestFrame = VideoFrame(cropW, cropH,
-outPixels)`). `UniformToFill` then zoomed the opaque crop content to cover the whole element rect,
-covering whatever was beneath (webcam). Fix: keep the single `CanvasScratch` buffer (no ring), feed
-the FULL `1920×1080` canvas to the compositor (`session.LatestFrame = VideoFrame(pixW, pixH,
-pixels)`), use the alpha crop only for the preview `WriteableBitmap`. Epoch increments per frame so
-array identity stays unique without the ring. The `0f441d8` insight was correct — the ring was the
-"additional crap."
+**Take-21 (`e002847`): PARTIAL FIX — transparency confirmed, but widget appeared shrunk and offset.**
+Root cause of transparency: `bccdb48` introduced `FindContentBounds` alpha cropping; the CROP was
+fed to the compositor (`session.LatestFrame = VideoFrame(cropW, cropH, outPixels)`). `UniformToFill`
+then zoomed the opaque crop content to cover the whole element rect, covering whatever was beneath
+(webcam). Fix: keep the single `CanvasScratch` buffer (no ring), feed the FULL `1920×1080` canvas
+to the compositor (`session.LatestFrame = VideoFrame(pixW, pixH, pixels)`), use the alpha crop only
+for the preview `WriteableBitmap`. Transparent margins revealed layers beneath — BUT the widget
+content appeared at ~1/3 scale and misplaced: the compositor's `UniformToFill` used `src=1920×1080`
+for a WebSource element sized 703×389, computing scale=0.366. The preview showed `Stretch="Fill"` with
+the CROPPED `PreviewBitmap` — completely different math, hence "looks correct in preview, wrong in
+recording."
+
+**Take-22 (`ed9d7c1`): FULL FIX.** `VideoFrame` gets `CropBounds?: (X,Y,W,H)` metadata. The full
+canvas still goes to the compositor, but `BlitContentRaw` detects `CropBounds` and switches from
+`UniformToFill` to Fill-style scaling (stretch to cover, no aspect preservation) using the actual
+crop dimensions. This matches the preview's `Stretch="Fill"` on the crop. Widget content now fills
+the element rect at the correct position; transparent margins still reveal layers beneath.
 
 ### Shrink / re-encode an image for the README (screenshots → small hero image)