Integrate Lightmaps into Game

[michaeleggers]

• Define binary format that gets output by the offline lightmapping tool.
• Modify polysoup and map_parser to get relevant data such as textures per face easier for using it in the lightmapping-tool.
• Read that binary and apply lightmaps to static level geometry.

[michaeleggers]

@hm-de-paoli You can now outpout the polygons to a binary format that contains all of the information you need:

struct PolySoupDataHeader {
    uint8_t     magic[4];   // must be PLYS
    uint8_t     version[4];
    uint64_t    numPolys;   // num of MapPolygons
    uint64_t    polySize; // sizeof(MapPolygon)
};

#pragma pack(push,1)
struct PolySoupData {
    PolySoupDataHeader  header;
    MapPolygon*         polys;
};
#pragma pack(pop)

As a reminder, a MapPolygon consists of:

struct QuakeMapVertex {
    glm::f64vec3  pos;
    glm::vec2     uv;
};

struct MapPolygon
{
    std::vector<QuakeMapVertex> vertices;
    glm::f64vec3                normal;
    // NOTE: (Michael): A single, solid color would be good for testing
    // the lightmapper. Thus, define a few solid color textures 
    // to use in TrenchBroom.
    std::string                 textureName;  // located in /game/textures/<*.png>
    uint64_t                    surfaceFlags; // eg. transparency, emissiveness, ...
    uint64_t                    contentFlags; // eg. water, slime, lava, ...
};

Also there is a new function:

void writePolySoupBinary(std::string fileName, const std::vector<MapPolygon>& polys);

That writes out a file containing one PolySoupData struct (see above). That should be everything you need. The texturefiles are not included as actual pixel data. We can actually do this in the future if we think this makes sense but it would mean that if we replace a texture in GIMP (or whatever) the whole file has to be rewritten, making it slightly inconvenient for the artist who maybe doesn't bake a new lightmap all the time. So for now, you have to load the textures yourself by looking in the textureName field of a MapPolygon.

Cheers, Michael.