Advanced Builds

Overview

A first build needs nothing on this page: QPlug Setup and Installation builds QPlug, its examples and its tests, drawing with the platform’s own graphics library. This page is for changing that: which parts are built, where the test validators come from, and which drawing backend the plugins use.

Build Options

Q_BUILD_PLUG

Build QPlug, its examples and its tests. OFF.

Q_BUILD_EXAMPLES

Build the examples, Q’s and QPlug’s. ON.

Q_BUILD_TEST

Build and register the tests, Q’s and QPlug’s. ON. Turning it off also skips fetching the validators.

Q_PLUG_DOWNLOAD_VALIDATORS

Download the pinned clap-validator and pluginval. ON.

CLAP_VALIDATOR, PLUGINVAL

Paths to your own validator binaries. Either one given takes precedence over the download.

Q_PLUG_VALIDATOR_DIR

Where the downloaded validators are cached, instead of the per-user default.

Drawing Backends

QPlug draws through Elements, and Elements through Artist, which has a backend for each graphics library it supports. Each platform has its own by default. Another is chosen at configure time with one of Elements' switches:

Backend Switch Platforms Default on

Quartz 2D

ELEMENTS_QUARTZ_2D

macOS

macOS

Direct2D

ELEMENTS_DIRECT2D

Windows

Windows

Cairo

ELEMENTS_CAIRO

macOS, Windows, Linux

Linux

Skia

ELEMENTS_SKIA

macOS, Windows, Linux

To draw with Skia, for example:

cmake -B build-skia -G Ninja -DCMAKE_BUILD_TYPE=Debug -DQ_BUILD_PLUG=ON -DELEMENTS_SKIA=ON
cmake --build build-skia

Give each backend a build directory of its own. The switches are cached, so turning one on in a directory that was configured with another leaves both set.

Skia, and Cairo on macOS and Windows, come as prebuilt libraries that configure downloads once and caches. Cairo on Linux is the system’s, from the packages listed in QPlug Setup and Installation. Skia on Linux also needs the OpenGL headers:

sudo apt-get install libgl1-mesa-dev libglu1-mesa-dev libegl1-mesa-dev

Current Limits

Backend and platform Status

Any backend on macOS, under pluginval

pluginval itself now and then crashes as it exits, in an AppKit window animation that outlives its editor window, after every test has passed. The crash shows most often with Cairo on a machine’s first run, when fontconfig builds its font cache.

CI builds and tests each platform’s own backend on every change to QPlug, and the others weekly.