Remove drawBitmap et al. from SkDevice
SkCanvas keeps its non-exotic drawBitmap calls for now but they
immediately wrap the bitmap in SkImage::MakeFromBitmap. This will
add a copy for mutable bitmaps, but this can be worked around by using
images directly (preferred), or marking the bitmap as immutable. In
practice, mutable bitmaps do not seem to be widely used so this is
deemed acceptable for now.
Several GMs are updated to mark the bitmaps as immutable in order to
avoid pixel churn in how CPU vs. GPU mipmaps are generated. As we move
towards explicit mipmap generation, this distinction will become less
critical, so I'm just avoiding it for now. See skbug.com/9337 for mipmap
proposal. The image diffs encountered in this CL directly related to
generating mipmaps for bitmaps already cached on the GPU vs. not on the
GPU yet.
It was decided to copy if mutable vs. never copying the bitmap because
it preserves the image guarantees the devices and canvas' rely on,
and imposing the need to inspect an image for mutability is undesired.
Bug: skia:10037, skia:9337
Change-Id: If152e6cae1e155ccf6bd2cd755895f3c7a0135a5
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/276004
Commit-Queue: Michael Ludwig <michaelludwig@google.com>
Reviewed-by: Mike Klein <mtklein@google.com>
diff --git a/RELEASE_NOTES.txt b/RELEASE_NOTES.txt
index 773e78f..92d06fc 100644
--- a/RELEASE_NOTES.txt
+++ b/RELEASE_NOTES.txt
@@ -7,9 +7,18 @@
Milestone 82
<Insert new notes here- top is most recent.>
+
+ * Removed drawBitmap and related functions from SkDevice; all public drawBitmap functions on
+ SkCanvas automatically wrap the bitmap in an SkImage and call the equivalent drawImage function.
+ Drawing mutable SkBitmaps will now incur a mandatory copy. Switch to using SkImage directly or
+ mark the bitmap as immutable before drawing.
+
* Removed "volatile" flag from SkVertices. All SkVertices objects are assumed to be
volatile (the previous default behavior).
+ * Removed exotic legacy bitmap functions from SkCanvas (drawBitmapLattic, drawBitmapNine); the
+ exotic SkImage functions still exist.
+
* Make it possible to selectively turn on/off individual encoders/decoders,
using skia_use_(libpng/libjpeg_turbo/libwebp)(decode/encode).
@@ -55,9 +64,9 @@
* SkSurface::ReplaceBackendTexture takes ContentChangeMode as a parameter,
which allow callers to specify whether retain a copy of the current content.
-
- * Enforce the existing documentation in SkCanvas::saveLayer that it ignores
- any mask filter on the restore SkPaint. The 'coverage' of a layer is
+
+ * Enforce the existing documentation in SkCanvas::saveLayer that it ignores
+ any mask filter on the restore SkPaint. The 'coverage' of a layer is
ill-defined, and masking should be handled by pre-clipping or using the
auxiliary clip mask image of the SaveLayerRec.