Skia Zig Bindings

Zig bindings for the famous Skia 2D Graphics Library.

Overview

This repository provides Zig bindings to the Skia C API. It builds Skia for multiple platforms and exposes the raw C headers to be used directly in Zig projects. No wrappers are provided—this is a low-level binding to the C layer only.

This repository is using the Skia fork from the Mono project, as they actively maintain a C wrapper for Skia (which is C++ only). We need C wrappers to bridge to Zig.

Features

• Pre-built Skia binaries
• Exposes the raw Skia C API headers to Zig
• Easy to import and use directly from Zig code without any dependencies or extra build steps

Project status

Warning: This wrapper is in a very early stage and is not stable for production use. Also not all features and plaforms are implemented.

• Skia build for Windows x86_64
• Skia build for macOS x86_64
• Skia build for macOS Apple Silicon
• Skia build for Linux

Getting Started

Usage

1. Import the skia-zig package into your project:

zig fetch --save https://github.com/basdp/skia-zig/releases/latest/download/skia-zig-package.zip

2. Add the dependency to your build.zig file, somewhere below b.addExecutable(...) or whatever you are building:

const skia_dep = b.dependency("skia-zig", .{
    .target = target,
    .optimize = optimize,
});
exe.root_module.addImport("skia-zig", skia_dep.module("skia-zig"));

3. You can now import skia-zig in your Zig code:

const skia = @import("skia-zig");

pub fn main() !void {
    const gr_glinterface = skia.gr_glinterface_create_native_interface();
    defer skia.gr_glinterface_unref(gr_glinterface);
    const gr_context = skia.gr_direct_context_make_gl(gr_glinterface) orelse return error.SkiaCreateContextFailed;
    defer skia.gr_direct_context_free_gpu_resources(gr_context);

    const gl_info = skia.gr_gl_framebufferinfo_t{
        .fFBOID = 0,
        .fFormat = gl.RGBA8,
    };

    const samples: c_int = ... // get from GL or something
    const stencil_bits: c_int = ... // get from GL or something

    const backendRenderTarget = skia.gr_backendrendertarget_new_gl(640, 480, samples, stencil_bits, &gl_info) orelse return error.SkiaCreateRenderTargetFailed;

    const color_type = skia.RGBA_8888_SK_COLORTYPE;
    const colorspace = null;
    const props = null;
    const surface = skia.sk_surface_new_backend_render_target(@ptrCast(gr_context), backendRenderTarget, skia.BOTTOM_LEFT_GR_SURFACE_ORIGIN, color_type, colorspace, props) orelse return error.SkiaCreateSurfaceFailed;
    defer skia.sk_surface_unref(surface);

    const canvas = skia.sk_surface_get_canvas(surface) orelse unreachable;

    while (/* app is running */) {
        skia.sk_canvas_clear(canvas, 0xffffffff);

        const fill = skia.sk_paint_new() orelse return error.SkiaCreatePaintFailed;
        defer skia.sk_paint_delete(fill);
        skia.sk_paint_set_color(fill, 0xff0000ff);
        skia.sk_canvas_draw_paint(canvas, fill);

        // Your Skia drawing here

        skia.sk_canvas_flush(canvas);
    }
}

Setting your ABI to MSVC on Windows

Skia requires the msvc ABI on Windows, so make sure you target that ABI. There are two possible options to do so (only one of these is necessary):

1. Set the target from the command line while building:

   zig build -Dtarget=x86_64-windows-msvc

2. Or better yet; replace the const target = ... line in your build.zig file:

   const target = b.standardTargetOptions(.{ .default_target = .{
       .abi = if (b.graph.host.result.os.tag == .windows) .msvc else null,
   } });