It's a big big job. The POV parser built into POV was written over many years in an incremental fashion. Writing a parser all in one go for the language as it currently stands is a mammoth job.
Excerpt from an old usened postBishop3D POV-Ray SDL parser
The Nathan O'Brien's IRTC entry winner 'Glory'imported into Bishop3D
The complexity, flexibility and lack of formal specification of POV-Ray scene description language (SDL) have been pointed over and over as the main reason why POV-Ray modelers don't support POV-Ray SDL import. But none of the reasons listed above represents an impossibility, they only suggest the difficulties involved in a task that no one could honestly expect to be simple.
POV-Ray SDL import capability is something that users always wished for a modeler. It has been part of Bishop3D project requisites since day one and, in many aspects, the whole modeler evolved around this requisite.
Bishop3D comes with a built-in parser and can import a descent subset of POV-Ray SDL code.
Current Limitations
- It only supports the syntax described in POV-Ray™ 3.6 documentation. The use of older syntax may only generate a warning but sometimes it will cause an error.
- It does not support the following objects (because Bishop3D does not currently support them):
- cubic
- isosurface
- julia_fractal
- parametric
- poly
- quadric
- quartic
- It does not support the keywords cutaway_textures, bounded_by, clipped_by and function (because Bishop3D does not currently support them).
- It does not support the functions inside, trace, vturbulence, min_extent, max_extent.
- It does not support spline identifiers.
- It does not support the directives fopen, fclose, write and read.
- It does not support the object pattern (because Bishop3D does not currently support it).
- The camera support is partial and currently includes only perspective and orthographic projections.
- The transformation/pigment/normal order is ignored for textures.