diff --git a/CHANGELOG.md b/CHANGELOG.md
index ce884dc..e3f392a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,12 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [0.31.0] - 2026-08-30
+
+### Changed
+
+- **`TextureRegionUpdater.UpdateRegion` — strided upload** (#484) — added `bytesPerRow` parameter (pre-v1.0 signature change). `0` = tightly packed rows (`w * bytesPerPixel`), matching WebGPU `ImageDataLayout.bytesPerRow`. Enables zero-copy dirty-band uploads from full-frame buffers (geckty, ggcanvas) without `extractRegion` memcpy.
+
 ## [0.30.0] - 2026-08-30
 
 ### Added
diff --git a/ROADMAP.md b/ROADMAP.md
index f836a1c..bfa35ba 100644
--- a/ROADMAP.md
+++ b/ROADMAP.md
@@ -4,8 +4,10 @@
 
 `gpucontext` is the shared foundation for the [gogpu](https://github.com/gogpu) ecosystem, providing interfaces and utilities for GPU resource sharing without circular dependencies.
 
-## Current: v0.29.0
+## Current: v0.31.0
 
+- `TextureRegionUpdater.UpdateRegion` strided upload (`bytesPerRow`, #484)
+- `DeviceProvider.DownlevelCapabilities()` (ADR-071)
 - `DeviceProvider.Features()` — query device capabilities (FeatureRayQuery, etc.)
 - SurfaceCompositor interface (ADR-067)
 - MouseButton/Modifiers stringers
@@ -19,6 +21,12 @@
 
 ## Released
 
+### v0.31.0 (2026-08-30)
+- `TextureRegionUpdater.UpdateRegion` — `bytesPerRow` parameter (pre-v1.0, #484)
+
+### v0.30.0 (2026-08-30)
+- `DeviceProvider.DownlevelCapabilities()` (ADR-071)
+
 ### v0.29.0 (2026-08-27)
 - `DeviceProvider.Features()` — gputypes.Features bitfield for capability queries
 
diff --git a/texture.go b/texture.go
index d9b6bc5..cd84f80 100644
--- a/texture.go
+++ b/texture.go
@@ -45,11 +45,18 @@ type TextureRegionUpdater interface {
 	// UpdateRegion uploads a sub-rectangle of pixel data to the texture.
 	// x, y is the top-left corner of the region in the texture.
 	// w, h is the size of the region.
-	// data must be exactly w * h * bytesPerPixel bytes (densely packed RGBA rows).
+	// bytesPerRow is the stride in bytes between consecutive rows in data.
+	// Pass 0 for tightly packed rows (w * bytesPerPixel) — WebGPU
+	// ImageDataLayout.bytesPerRow semantics. This eliminates the need for
+	// callers to extractRegion-copy dirty bands from a full-frame buffer.
+	//
+	// When bytesPerRow is 0, data must be exactly w * h * bytesPerPixel bytes.
+	// When bytesPerRow > 0, data must be at least
+	// bytesPerRow*(h-1) + w*bytesPerPixel bytes (last row need not be padded).
 	//
 	// Returns error if the region exceeds texture bounds, data size is invalid,
-	// or the texture has been destroyed.
-	UpdateRegion(x, y, w, h int, data []byte) error
+	// bytesPerRow is too small, or the texture has been destroyed.
+	UpdateRegion(x, y, w, h, bytesPerRow int, data []byte) error
 }
 
 // TextureDrawer provides texture drawing capabilities for 2D rendering.