Build Scripts

This folder holds common build scripts accessed via the various npm run commands. Codegen is executed when calling npm install in order to generate all artifacts needed for the build to pass

Bundeling all the code

The bundling process can be split into several steps:

npm run build-css This command will compile the css code and create the css file.

npm run build-prod and npm run build-dev These commands will use rollup to bundle the code. This is where the magic happens and uses some files in this folder.

banner.ts is used to create a banner at the beginning of the output file

rollup_plugins.ts is used to define common plugins for rollup configurations

rollup_plugin_minify_style_spec.ts is used to specify the plugin used in style spec bundeling

In the rollup folder there are some files that are used as linking files as they link to other files for rollup to pick when bundling.

Rollup is generating 3 files throughout the process of bundling:

index.ts a file containing all the code that will run in the main thread.

shared.ts a file containing all the code shared between the main and worker code.

worker.ts a file containing all the code the will run in the worker threads.

These 3 files are then referenced and used by the bundle_prelude.js file. It allows loading the web worker code automatically in web workers without any extra effort from someone who would like to use the library, i.e. it simply works.

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npm run codegen

The codegen command runs the following three scripts, to update the corresponding code files based on the v8.json style source, and other data files. Contributors should run this command manually when the underlying style data is modified. The generated code files are then committed to the repo.

generate-struct-arrays.ts

Generates data/array_types.ts, which consists of:

• StructArrayLayout_* subclasses, one for each underlying memory layout
• Named exports mapping each conceptual array type (e.g., CircleLayoutArray) to its corresponding StructArrayLayout class
• Specific named StructArray subclasses, when type-specific struct accessors are needed (e.g., CollisionBoxArray)

generate-style-code.ts

Generates the various style/style_layer/[layer type]_style_layer_properties.ts code files based on the content of v8.json. These files provide the type signatures for the paint and layout properties for each type of style layer.

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Generate Release Nodes

release-notes.js Used to generate release notes when releasing a new version