• Civilization 2: Creating a new advance and a new unit

    The format for a technology advance looks like this:

    Advance Name, AI Value, AI Modifier, Preq1, Preq2, Epoch, Knowledge Category

    In the RULES.TXT file in the @CIVILIZE section, the Advanced Flight advance appears like so:

    Advanced Flight, 4, -2, Rad, Too, 3, 4; Afl

    Here are the definitions for each value:



    AI Value How important the AI considers the advance when choosing the next advance to research.
    AI Modifier Positive numbers are valued more by "peaceful" leaders, negative numbers are valued by "militaristic" leaders.
    Preq1, Preq2 The advances that you must have before you can research this one.
    Epoch Ancient, Renaissance, Industrial, or Modern (0, 1, 2, 3).
    Knowledge Category Military, Economic, Social, Academic, or Applied (0, 1, 2, 3, or 4).

    The abbreviation for the advance is listed after the semicolon.

    The last three entries in the advances list (@CIVILIZE) are for user-created advances. Let's create an advance we'll call "VTOL" (short for Vertical Takeoff and Landing), which would be something a Harrier attack aircraft would need. However, the unit we'll create with this advance is a ship; the Tarawa-class assault ship, which can carry aircraft and land units.

    The VTOL advance would look like this:

    VTOL, 3, -1, CA, nil, 3, 0; U1

    The AI would consider this a moderately useful but not high-priority advance, and it would be more compelling for militaristic leaders. It requires combined arms, but nothing else (that's what the "nil" entry means.) It's a modern era advance and is military in nature.


    Okay, now that we have a new cilization advance, let's create the unit. The unit descriptions are listed like so:

    Name, Expires, Domain, Move, Range, Attack, Defense, Hits, Firepower, Cost, Hold, Preq, Flags
    A settler unit, as an example, would look like this:

    Settlers, Exp, 0, 1, 0, 0a, 1d, 2h, 1f, 4, 0, 5, nil, 000000000000000

    Here are the definitions of each value:



    Name The name of the unit type.
    Expires After this civilization advance, new units of this type can no longer be made.
    Domain Movement domain --- ground, sea, or ait (0, 1, or 2).
    Move This is the number of movement points the unit has.
    Range Fuel supply carried by air units.
    Attack Chance to hit opponent when attacking.
    Defense Chance to score hit when defending.
    Hits The number of points (x10) of damage the unit can sustain before being destroyed.
    Firepower Each hit causes this many points of damage.
    Cost Build cost of the unit, in shield rows.
    Hold How many units a ship may carry.
    Role The number designates what special abilities a unit has (5 gives the unit Settler abilities; 0 designates an offense unit).
    Preq The civilization advance that must be researched before this unit is built.
    Flags A special number, in binary format, that controls special advantages and restrictions. This number is 15 digits wide, but it's the position that's important. If the second digit from the right is 1, then the unit can ignore zones of control. This number would look like: 000000000000010. The RULES.TXT file lists all the possible positions and what special abilities they confer.

    So, since we've already created the VTOL technology, we can now create the resultant Tarawa assault vessel. The Tarawa statistics would look like this:

    Tarawa, nil, 2, 6, 0, 2a, 6d, 4h, 2f, 10, 3, 2, U1, 000000010000001

    The Tarawa is an assault carrier, but it's only capable of carrying VTOL strike aircraft and helicopters. It also carries a contingent of marines.* Civ II doesn't like "dual role" units, so I couldn't have it carry both land units and aircraft. Having an assault ship carry stealth bombers would have been unrealistic, anyway. Since the Tarawa class aircraft is used for ground support, I generalized the ability by giving it the same capabilities as an Aegis cruiser and allowing it to carry three land units in the hold. Of course, you can't build one unless you have researched VTOL technology.

    Now we have a new tech and a new unit. But wait --- what's it going to look like?

    The generic replacement for a sea unit is a bit goofy (a catamatan), so I found a photograph of the Tarawa on the Internet. Using Photoshop, I reduced it to a 64-pixel-wide icon and pasted it into the UNITS.GIF file, making sure to use the color pallette from UNITS.GIF. (Note: you don't need an expensive package like Photoshop; Paintshop Pro, version 3.12 works just as well, and it's shareware.)

    Next, the Tarawa vessel has to sound right when it's attacking. Civilization II uses a sound file name CUSTOM3.WAV for the third user unit slot (which is where I put the Tarawa entry). I simply went into the SOUND directory (in the Civ II game directory) and copied NAVBTTL.WAV to CUSTOM3.WAV.

    Now the customization is complete: a new technology, which spawns a new type of unit, complete with graphics and sound.
    This article was originally published in forum thread: Civilization 2: Creating a new advance and a new unit started by Martin Gühmann View original post