Andros Fenollosa
27a98a1c36
Cursor-only motion takes redisplay's fast path: no render cycle opens, and the CADisplayLink stops firing while Emacs idles, so with animations enabled the moved cursor overlay was never presented (it appeared frozen until the next input event) and rings/trails never animated between events. Three fixes: note_cursor composites immediately when no cycle is open; the animation step is factored into tickWithDt: and exposed as mtl-anim-tick, driven by a 30fps Lisp timer while animations are enabled (the same mechanism that drives video playback); and burst particles use the real cursor color instead of a hardcoded pale tint that was invisible on light backgrounds. |
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| admin | ||
| build-aux | ||
| cross | ||
| doc | ||
| etc | ||
| exec | ||
| java | ||
| leim | ||
| lib | ||
| lib-src | ||
| lisp | ||
| lwlib | ||
| m4 | ||
| modules | ||
| msdos | ||
| nextstep | ||
| nt | ||
| oldXMenu | ||
| src | ||
| test | ||
| .clang-format | ||
| .clangd | ||
| .dir-locals.el | ||
| .gitattributes | ||
| .gitignore | ||
| .gitlab-ci.yml | ||
| .mailmap | ||
| autogen.sh | ||
| BUGS | ||
| ChangeLog.1 | ||
| ChangeLog.2 | ||
| ChangeLog.3 | ||
| ChangeLog.4 | ||
| ChangeLog.5 | ||
| ChangeLog.android | ||
| config.bat | ||
| configure.ac | ||
| CONTRIBUTE | ||
| COPYING | ||
| GNUmakefile | ||
| INSTALL | ||
| INSTALL.REPO | ||
| make-dist | ||
| Makefile.in | ||
| README | ||
| README.md | ||
emacs-gpu
GNU Emacs with a GPU-accelerated display backend.
On macOS it renders with native Apple Metal: text goes through a GPU glyph atlas, images and inline video are textures, and the whole frame is composited by the GPU instead of CoreGraphics. The output is pixel-accurate against the stock Cocoa backend.
OpenGL support for GNU/Linux and Windows is planned but not implemented
yet. The drawing logic is already platform-neutral (src/gfxterm.c)
behind a small driver interface (src/gfxdrv.h); an OpenGL driver only
needs to implement that interface (src/glterm.c is the documented
skeleton). Contributions welcome.
Status: experimental, under active development.
Note: I am not answering issues for now. Feel free to open them as a public record (they will be read eventually), but do not expect a reply at this stage.
Demos
Inline video playing inside a buffer, decoded by AVFoundation straight
into Metal textures (mtl-video-insert):
An animated GIF playing next to font-locked code scrolling, all composited by the GPU:
GPU cursor effects (mtl-animations), here the sonicboom mode:
Building on macOS
Requires Xcode (or the Command Line Tools) and the usual Emacs build
dependencies (brew install autoconf automake gnutls texinfo pkg-config).
./autogen.sh
SDK=$(xcrun --sdk macosx --show-sdk-path)
CC="xcrun clang" OBJC="xcrun clang" \
CFLAGS="-isysroot $SDK" CPPFLAGS="-isysroot $SDK" OBJCFLAGS="-isysroot $SDK" \
./configure --with-ns --with-mtl
make -j$(sysctl -n hw.ncpu)
The binary is src/emacs (or install the app bundle from nextstep/).
Enabling the GPU backend
Emacs starts with the regular Cocoa backend; switch a frame to Metal with:
(add-to-list 'load-path "/path/to/emacs-gpu/lisp")
(require 'mtl)
(mtl-enable)
Extras once enabled:
(mtl-video-insert "video.mp4" 480 270 t) ; inline video, follows scrolling
(mtl-animations t) ; GPU cursor effects (experimental)
(mtl-draw-stats) ; renderer counters
How it works
redisplay engine (xdisp.c, untouched)
↓
src/gfxterm.c platform-neutral drawing policy
↓
src/gfxdrv.h driver interface (~25 ops)
↓
src/mtlterm.m Metal driver: glyph atlas (CoreText → R8 texture),
render cycle on a persistent texture, AVFoundation
video through CVMetalTextureCache
License
GNU General Public License v3 or later, same as GNU Emacs.