Shaders Plugin Cannot Parse Recursive Addnormals() [closed]

[OrbWeaver]

The current shader parser is coded to accept addnormals(<imagemap>, <imagemap>), but does not accept addnormals(<mapexpression>, <mapexpression> recursively. This causes a parse failure on tdm_ai_builders.mtr (for example) since there is a shader which contains addnormals(image, heightmap(image)), which means that the build guard textures are not loaded and the builder guard shows up with notex.bmp.

 

I will probably handle this by adding another function to parse the addnormals() expression recursively. I have also added a catch() block in parseShaderFile() to print out the parse exceptions, which for some reason were previously being silently discarded leaving us unaware just how many .mtr files were not properly parsed.

[greebo]

This seems to be my fault, as I refactored the parser as my first programming task. Thanks for looking into it!

[OrbWeaver]

The problem was that the exceptions were hidden, therefore you would assume that the code was working rather than seeing immediately that there was a problem. I am not entirely sure why this was, but at least they are visible now.

[OrbWeaver]

Very basic parsing functionality is now there -- the addnormals() function is parsed recursively, but the result is probably useless as only the last image map seen will be saved. I need to change this so that a propery tree-based data structure is constructed from the recursive parse, which can be evaluated at a later time in order to produce the correct image.

[OrbWeaver]

I am closing this since the syntax is parsed correctly, although the MapExpression implementation should be improved (for instance, there should be a way of generating the resulting image from a parse tree rather than just searching for any image map to display).