ofxAlembic

ofxAlembic is an openFrameworks addon for reading, writing, and drawing Alembic scene data. It supports points, curves, polygon meshes, transforms, and cameras using the Alembic Ogawa backend.

Requirements

• openFrameworks 0.12.1
• macOS 11.0 or later with Xcode 15 or later
• Windows 11 with Visual Studio 2022, x64 Release builds

The addon bundles:

• Alembic 1.8.12
• Imath 3.2.3
• Universal macOS static libraries for Intel and Apple Silicon
• Windows x64 libraries and runtime DLLs

HDF5 support is not included. Use Alembic files written with the Ogawa backend. Build settings, source tags, and binary checksums are recorded in libs/DEPENDENCIES.md.

Installation

Clone the addon into the addons directory of an openFrameworks 0.12.1 installation:

cd /path/to/openFrameworks/addons
git clone https://github.com/perfume-dev/ofxAlembic.git

Add ofxAlembic to a project with the openFrameworks Project Generator. No additional system libraries are required.

Reading an Alembic file

#include "ofxAlembic.h"

ofxAlembic::Reader reader;

if (!reader.open("scene.abc")) {
    ofLogError() << "Could not open scene.abc";
    return;
}

reader.setTime(1.0);

ofMesh mesh;
if (reader.get("/model/modelShape", mesh)) {
    mesh.draw();
}

Object paths can be either local names or full Alembic paths. Check the return value from open() and typed get() calls before using their output.

Writing an Alembic file

#include "ofxAlembic.h"

ofxAlembic::Writer writer;

if (!writer.open("output.abc", 30.0f)) {
    ofLogError() << "Could not create output.abc";
    return;
}

std::vector<glm::vec3> points = {
    {0.0f, 0.0f, 0.0f},
    {100.0f, 0.0f, 0.0f}
};

writer.addPoints("/points", points);
writer.close();

Writer paths must start with /. Create a parent object before adding child objects below it.

Examples

• example-read: reads and draws meshes, points, and curves
• example-write: writes animated geometry and a camera, then reads it back
• example-shader: draws Alembic meshes with a shader

Generate each example project with the Project Generator before opening it in Xcode or Visual Studio.

Supported data

Schema	Read	Write
Points	Yes	Yes
Curves	Yes	Yes
Polygon mesh	Yes	Yes
Transform	Yes	Yes
Camera	Yes	Yes

Polygon meshes are triangulated when read. Mesh writing currently expects triangle topology.

Previous openFrameworks releases

• macOS, OF 0.10.0–0.11.2: use commit b29dbd5
• macOS, OF 0.9.8: use commit 9f6ad89
• Windows, OF 0.10.0–0.11.2: use the P-A-N fork
• Windows, OF 0.9.8: use the hanasaan fork

Older snapshots are not covered by the current build checks or security updates.

Contributing

See CONTRIBUTING.md for the development and pull-request workflow. Please report security problems according to SECURITY.md.

License

ofxAlembic is released under the MIT License. See LICENSE.txt. Alembic and Imath retain their respective licenses in libs/.