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COA File Format Explained

The .coa (Caligari Object ASCII) format is the plain-text version of trueSpace's .cob 3D object format. It stores static geometry, vertex, and material data in human-readable ASCII instead of a compiled binary structure.

	Icon	Extension	Original Software	Year	Primary Industry	Geometry	UV Maps	Textures	PBR	Animation	Rigging	Open Use
		.COA	TrueSpace	1994	Game Development Architecture Product Visualization	None	–	–	–	✔	–	–
COA File Format Details What It Stores The .coa (Caligari Object ASCII) format is the plain-text counterpart to TrueSpace's binary .cob file. It stores static 3D geometry—including vertices, polygon faces, and UV texture coordinates—along with basic material properties, all written in a human-readable text structure. Primary Use Cases Bridging the interoperability gap between early 3D software applications lacking support for compiled binary formats. Allowing technical artists to open 3D models in standard text editors for manual debugging and data inspection. Serving as an accessible format for developers writing custom pipeline scripts and conversion utilities. Strengths Human-readable text structure eliminates the need for specialized software to view the raw data. Highly accessible for programmers parsing 3D geometry without needing to reverse-engineer binary code. Immune to the cross-platform byte-order compatibility issues common in legacy binary formats. Limitations Results in massively bloated file sizes due to storing floating-point math as plain text. Significantly slower for applications to parse and load, making it highly inefficient for complex or high-polygon meshes. Common Software Support Native support was largely restricted to Caligari TrueSpace and specialized 3D conversion suites of the era, such as Okino PolyTrans or Deep Exploration. Today, the format is entirely obsolete in modern digital content creation software, requiring community-written legacy plugins to import into programs like Blender. Additional Notes The .coa format is a relic of an era when proprietary 3D ecosystems were heavily siloed. Much like the enduring Wavefront .obj format, text-based object formats were a necessary, albeit inefficient, fallback to ensure 3D geometry could be transferred between competing software packages before modern open standards existed.