5b4b437b30
The previous implementation was *extremely* expensive. It relied on loading a binary JSON file from resources (which involved decompressing it), then extracting information out of it to build a gradient. Already-loaded gradients were kept in a local cache, which had to be mutex protected. Instead, this patch extends the gradient generator to build static arrays filled with the web gradient data, sitting in .rodata. These arrays are used when building QGradient objects with a web gradient. No explicit mutex protection is necessary, since accesses will just read from the arrays. As benefits, this patch removes: * the binary json representation from QtGui's resources (~4KB compressed, ~50KB uncompressed) * the overhead of reading from the JSON for each used web gradient; * the startup costs of registering the webgradients in the resources; * all the overhead of mutex locking when building such gradients; * all the runtime memory allocations to load, parse and cache the web gradients (including the memory + CPU spike on first load due to the uncompression of the JSON data, as well as a couple of deep copies). Change-Id: If5c3d704430df76ce8faf55ee75ebd4639ba09c4 Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@qt.io> Reviewed-by: Ulf Hermann <ulf.hermann@qt.io> Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org> Reviewed-by: Thiago Macieira <thiago.macieira@intel.com> Reviewed-by: Edward Welbourne <edward.welbourne@qt.io> |
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| .. | ||
| .gitignore | ||
| gradientgen.cpp | ||
| gradientgen.js | ||
| gradientgen.pro | ||
| package-lock.json | ||
| package.json | ||
| qt_attribution.json | ||
| README | ||
| WEBGRADIENTS_LICENSE.txt | ||
| webgradients.css | ||
Regeneration of gradients: 0) Grab a new .css for the webgradients 1) Run the gradientgen.js script (requires node): gradientgen.js enum webgradients.css # will regen the enumeration names (on stdout) gradientgen.js json webgradients.css # will regen the actual gradients (on stdout) 2) Build gradientgen.pro 3) Run gradientgen, passing the json as stdin, the result will be on stdout