Linear Pendulum trick

@SolidClass = func_map2prop : "Brushes for Map2Prop to turn into a model"
[
    spawnflags(flags) =
    [
        1 : "Disable" : 0
    ]

    outname(string) : "Exported model's name"
    outdir(string) : "Exported model subfolder"
    gamma(string) : "Gamma (default 1.8)" : "1.8"
    smoothing(string) : "Smoothing threshold (0 disables)" : "60.0"
    scale(string) : "Scale" : "1.0"
    rotate(string) : "Rotate" : "0.0"
    convert_to(choices) : "Classname after conversion" : 0 =
    [
        0: "cycler"
        1: "cycler_sprite"
        2: "env_sprite"
        3: "item_generic"
        4: "monster_furniture"
        5: "monster_generic"
    ]
]

typedef struct {
    char[4] magic;                      // File format magic number, "JHMF" in ASCII encoding
    int32 version;                      // File format version (currrently 122)
    int32 ep_count;                     // Number of recent export paths
    p_char[ep_count] export_paths;      // Recent export paths
    bg_image[3] bg_images;              // Background images
    int32 group_count;                  // Number of groups in the map
    Group[group_count] groups;          // Group objects
    int32 visgroup_count;               // Number of VisGroups
    VisGroup[visgroup_count] visgroups; // VisGroups objects
    Vector cordon_min;                  // Minimum corner of the Cordon box
    Vector cordon_max;                  // Maximum corner of the Cordon box
    int32 camera_count;                 // Number of Camera objects
    Camera[camera_count] cameras;       // Camera objects
    int32 path_count;                   // Number of path objects
    Path[path_count] paths;             // Path objects (created with the Path tool)
    Entity[] entities;                  // All entities including worldspawn, read until the end of the file
} Jmf;

typedef struct {
    p_char path;                        // Background image path
    double scale;                       // Image scale
    int32 luminance;                    // Image brightness (0-255)
    int32 filtering;                    // Image filtering (0=nearest, 1=linear)
    int32 invert;                       // Invert image colours
    int32 offset_x;                     // Image horizontal offset from center
    int32 offset_y;                     // Image vertical offset from center
    byte[4] unknown;
} bg_image