tess2-wasm

Port of Libtess2 to wasm

How to build:

• Install emcc
• Install cmake
• Install Ninja (for other build tools edit configuarion script)
• Run npm run release

How to use:

Spawn a wrapped to wasm Tess class

createTess2Wasm().then({Tess} => {
    const tess = new Tess();
    tess.addContours([0,0, 0,1, 1,1, 1, 0]);
    const result = tess.tesselate({
        windingRule: 0, // ODD,
        elementType: 0, // polygon,
        polySize: 3,
        vertexSize: 2
    });
    tess.dispose();
});

NOTE! Because this is WASM, need call a Tess::dispose to avoid leaks;

COMPARASION: Simle сomparison: Earcut, Tess-TS, Tess-WASM

https://www.pixiplayground.com/#/edit/komaAjZ74MSHEKO9T3_5z

SIMD

Current implementation not use SIMD instruction, package include SIMD what emitted by LLVM -msimd128 instruction. SIMD version slower and bigges that no-simd bundle in regular tests.

..

Libtess2

Version 1.0.1

This is refactored version of the original libtess which comes with the GLU reference implementation. The code is good quality polygon tesselator and triangulator. The original code comes with rather horrible interface and its' performance suffers from lots of small memory allocations. The main point of the refactoring has been the interface and memory allocation scheme.

A lot of the GLU tesselator documentation applies to Libtess2 too (apart from the API), check out http://www.glprogramming.com/red/chapter11.html

Simple bucketed memory allocator (see Graphics Gems III for reference) was added which speeds up the code by order of magnitude (tests showed 15 to 50 times improvement depending on data). The API allows the user to pass his own allocator to the library. It is possible to configure the library so that the library runs on predefined chunk of memory.

The API was changed to loosely resemble the OpenGL vertex array API. The processed data can be accessed via getter functions. The code is able to output contours, polygons and connected polygons. The output of the tesselator can be also used as input for new run. I.e. the user may first want to calculate an union all the input contours and the triangulate them.

The code is released under SGI FREE SOFTWARE LICENSE B Version 2.0. http://oss.sgi.com/projects/FreeB/

Mikko Mononen [email protected]