Magnum Graphics Middleware

Magnum is a modular engine. Additional functionality is often provided in separate repositories to keep the core engine small:

• Corrade: The main dependency of Magnum; a multiplatform utility library.
• Magnum Bootstrap: Bootstrap projects for various use cases to help you get running quickly.
• Magnum Plugins: Importer plugins for image, font, audio, and 3D model formats.
• Magnum Integration: Integrations with external math and physics libraries.
• Magnum Examples: A collection of usage examples ranging from 'Hello World' to complex 3D model viewers.
• Magnum Extras: A playground for testing new APIs and specialized functionality.
• Magnum Bindings: Language bindings (e.g., Python).
• Magnum Singles: Single-header versions of Magnum functionality for easy integration.

To begin using Magnum in your project, follow the official guide for downloading, building, installing, and starting usage: https://doc.magnum.graphics/magnum/getting-started.html.

For detailed instructions on the build process, refer to the building documentation: https://doc.magnum.graphics/magnum/building.html.

Once installed, you can explore the library through:

• Tutorials and examples: https://doc.magnum.graphics/magnum/example-index.html
• Feature guide: https://doc.magnum.graphics/magnum/features.html

Use Magnum::DebugTools::CompareImageToFile to compare an in-memory image to an image file. This is a combination of CompareImage and CompareImageFile.

Like CompareImageFile, it supports the --save-diagnostic option to save the actual image data to a file upon failure.

Use Magnum::DebugTools::CompareImageFile to compare an in-memory image against an image loaded from a file. This requires a Trade::AbstractImporter plugin manager to load the file.

If the comparison fails and the --save-diagnostic option is used with the Corrade::TestSuite::Tester, the actual image data will be saved to the specified directory using the Trade::AnyImageConverter plugin.

Use Magnum::DebugTools::CompareImage to compare two in-memory images (e.g., Magnum::ImageView2D) for equality. Since real-world images often have slight variations due to hardware or compression, you can provide maxThreshold (maximum delta for a single pixel) and meanThreshold (average delta over all pixels) to allow for controlled differences.

In a Corrade::TestSuite, use CORRADE_COMPARE_AS() for exact bit-equality or CORRADE_COMPARE_WITH() to specify thresholds.

Magnum provides graphics abstraction and platform independence across the following environments:

Supported Platforms:

• Linux and embedded Linux
• Windows (MSVC, clang-cl, MinGW, and Windows RT/Store/Phone)
• macOS and iOS
• Android
• Web (via Emscripten using asm.js or WebAssembly)

Supported Graphics APIs:

• OpenGL 2.1 through 4.6 (including core profile and modern extensions)
• OpenGL ES 2.0, 3.0–3.2 (with extensions matching desktop OpenGL)
• WebGL 1.0 and 2.0 (with extensions matching desktop OpenGL)

You can use Corrade::Containers::StridedArrayView2D containing raw pixel data (e.g., from ImageView::pixels()) as the 'actual' input for CompareImage and CompareImageToFile. This allows for flexible comparisons, such as comparing flipped pixel data or sliced channels (e.g., comparing RGB data from a 4-component framebuffer against a 3-component ground truth).

The pixel format is automatically detected from the type of the view (e.g., Magnum::Vector3ub).

Use Magnum::DebugTools::CompareMaterial to compare two Magnum::Trade::MaterialData instances within a Corrade::TestSuite. The comparator detects differences in material type, layer count, attributes, and attribute values.

When a comparison fails, it provides detailed output via printMessage describing the specific differences (e.g., different attribute types or mismatched values). It supports all Magnum::Trade::MaterialAttributeType values.

The Corrade::TestSuite::Comparator<Magnum::DebugTools::CompareMaterial> specialization provides the following interface for material comparison:

• ComparisonStatusFlags operator()(const Magnum::Trade::MaterialData& actual, const Magnum::Trade::MaterialData& expected): Compares two material data instances and returns the status flags.
• void printMessage(ComparisonStatusFlags flags, Utility::Debug& out, Containers::StringView actual, Containers::StringView expected) const: Prints a detailed description of the differences between the actual and expected materials to the provided debug output.