Sandbox.wiki
changeset 1786 006999425a5c
parent 1739 2655c9d7ef80
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    29   * Bullet 2
    29   * Bullet 2
    30   * Bullet 2
    30   * Bullet 2
    31    * Bullet 3
    31    * Bullet 3
    32    * Bullet 3
    32    * Bullet 3
    33   * Bullet 2
    33   * Bullet 2
       
    34 
       
    35 ---
       
    36 
       
    37 #summary List of gear-related functions in the Lua API
       
    38 
       
    39 = Lua API: Gear functions =
       
    40 This is a list of all functions in the [LuaAPI Lua API] that are related to gears and visual gears. Refer to [LuaGuide] for an introduction into gears.
       
    41 
       
    42 <wiki:toc max_depth="3"/>
       
    43 
       
    44 == Functions for creating gears ==
       
    45 
       
    46 === `AddGear(x, y, gearType, state, dx, dy, timer)` ===
       
    47 This creates a new gear at position x,y (measured from top left) of kind `gearType` (see [GearTypes Gear Types]).  Gears are dynamic objects or events in the world that affect the gameplay, including hedgehogs, projectiles, weapons, land objects, active utilities and a few more esoteric things.
       
    48 The initial velocities are `dx` and `dy`. All arguments are numbers. The function returns the `uid` of the gear created. Gears can have multple states at once: `state` is a bitmask, the flag variables can be found in [States].
       
    49 
       
    50 Example:
       
    51 
       
    52 <code language="lua">    local gear = AddGear(0, 0, gtTarget, 0, 0, 0, 0)
       
    53     FindPlace(gear, true, 0, LAND_WIDTH)</code>
       
    54 
       
    55 === `AddVisualGear(x, y, visualGearType, state, critical [, layer])` ===
       
    56 This attempts to create a new visual gear at position x,y (measured from top left) of kind `visualGearType` (see [VisualGearTypes Visual Gear Types]).  Visual gears are decorational objects which are usually used for purely decorational graphical effects.  They have no effect on gameplay.  Visual gears are not the same as gears, but they share some similarities.
       
    57 
       
    58 The function returns the `uid` of the visual gear created or `nil` if creation failed.  There is no guarantee that a visual gear will spawn.  *IMPORTANT: Do not rely on visual gears to spawn*. *Always* be prepared for this function to return `nil`.
       
    59 
       
    60 Set `critical` to `true` if the visual gear is crucial to gameplay and must always be spawned when in-game.  Use `false` if it is just an effect or eye-candy, and its creation can be skipped when in fast-forward mode (such as when joining a room).
       
    61 
       
    62 You can set an optional `layer` to specify which visual gears get drawn on top.
       
    63 
       
    64 Most visual gears delete themselves eventually.
       
    65 
       
    66 *NOTE:* Visual gears *must* only be used for decorational/informational/rendering purposes. *Never* use the visual gear's internal state to manipulate anything gameplay-related. Visual gears are not safe for reliable storage and using them as that would lead to strange bugs.
       
    67 
       
    68 *NOTE:* Since 0.9.25, visual gears will never spawn when Hedgewars is run in a testing mode (i.e. not as the real game), so don't rely for visual gears to spawn even if they're critical.
       
    69 
       
    70 Example:
       
    71 
       
    72 <code language="lua">  -- adds an non-critical explosion at position 1000,1000. Returns 0 if it was not created.
       
    73     local vgear = AddVisualGear(1000, 1000, vgtExplosion, 0, false) 
       
    74 </code>
       
    75 
       
    76 === `AddHog(hogname, botlevel, health, hat)` ===
       
    77 Adds a new hedgehog for current team (last created one with the `AddTeam` function), with a bot level, an initial health and a hat.
       
    78 
       
    79 `botlevel` ranges from `0` to `5`, where `0` denotes a human player and `1` to `5` denote the skill level of a bot, where `1` is strongest and `5` is the weakest. Note that this is the reverse order of how the bot level is displayed in the game. Note that mixing human-controlled and computer-controlled hedgehogs in the same team is not permitted, but it is permitted to use different computer difficulty levels in the same team.
       
    80 
       
    81 Returns the gear ID.
       
    82 
       
    83 *Warning*: This only works in singleplayer mode (e.g. missions). Also, Hedgewars only supports up to 64 hedgehogs in a game.
       
    84 
       
    85 Example:
       
    86 
       
    87 <code language="lua">    local player = AddHog("HH 1", 0, 100, "NoHat") -- botlevel 0 means human player
       
    88     SetGearPosition(player, 1500, 1000)
       
    89     -- hint: If you don't call `SetGearPosition`, the hog spawns randomly</code>
       
    90 
       
    91 === `AddMissionHog(health)` (0.9.25) ===
       
    92 Add a hedgehog for the current team, using the player-chosen team identity when playing in singleplayer missions. The “current team” is the last team that was added with `AddMissionTeam` or `AddTeam`.
       
    93 
       
    94 The name and hat match the player's team definition. The hog is also always player-controlled.
       
    95 
       
    96 Examples:
       
    97 <code language="lua">-- Add player team with 3 hogs
       
    98 AddMissionTeam(-1)
       
    99 AddMissionHog(100)
       
   100 AddMissionHog(100)
       
   101 AddMissionHog(100)</code>
       
   102 
       
   103 <code language="lua">-- You can also mix mission hogs with “hardcoded” hogs.
       
   104 -- This adds a player team with 2 hogs taken from the player team and 1 hog with a hardcoded name, botlevel and hat.
       
   105 AddMissionTeam(-2)
       
   106 AddMissionHog(100)
       
   107 AddMissionHog(100)
       
   108 AddHog("My Hardcoded Hog", 0, 100, "NoHat")
       
   109 </code>
       
   110 
       
   111 === `SpawnHealthCrate(x, y, [, health])` ===
       
   112 Spawns a health crate at the specified position. If `x` and `y` are set to 0, the crate will spawn on a random position (but always on land). Set `health` for the initial health contained in the health crate. If not set, the default health (`HealthCaseAmount`) is used. Do not use a negative value for `health`.
       
   113 
       
   114 === `SpawnSupplyCrate(x, y, ammoType [, amount])` (0.9.24) ===
       
   115 Spawns an ammo or utility crate at the specified position with the given ammo type and an optional amount (default: 1). The crate type is chosen automatically based on the ammo type.
       
   116 Otherwise, this function behaves like `SpawnAmmoCrate`.
       
   117 
       
   118 === `SpawnAmmoCrate(x, y, ammoType [, amount])` ===
       
   119 Spawns an ammo crate at the specified position with content of `ammoType` (see [AmmoTypes Ammo Types]). Any `ammoType` is permitted, an ammo crate is spawned even if the ammo is normally defined as an utility.
       
   120 If `ammoType` is set to `amNothing`, a random weapon (out of the available weapons from the weapon scheme) will be selected. If `x` and `y` are set to 0, the crate will spawn on a random position (but always on land). The `amount` parameter specifies the amount of ammo contained in the crate. If `amount` is `nil` or `0`, the value set by `SetAmmo` is used, or if `SetAmmo` has not been used, it falls back to the weapon scheme's value. If `amount` is equal to or greater than `AMMO_INFINITE`, the amount is infinite.
       
   121 
       
   122 Note that in Lua missions, the default number of ammo in crates is 0, so it has to be set to at least 1 with `SetAmmo` first, see the example:
       
   123 
       
   124 Example:
       
   125 
       
   126 <code language="lua">    SetAmmo(amGrenade, 0, 0, 0, 1) -- grenade ammo crates now contain 1 grenade each
       
   127     SpawnAmmoCrate(0, 0, amGrenade) -- spawn grenade ammo crate at random position</code>
       
   128 
       
   129 === `SpawnUtilityCrate(x, y, ammoType [, amount])` ===
       
   130 Spawns an utility crate with some ammo at the specified position. The function behaves almost like `SpawnAmmoCrate`, the differences are 1) the crate looks different and 2) if `ammoType` is set to `amNothing`, a random utility out of the set of available utilities from the weapon scheme is chosen as content.
       
   131 
       
   132 Example:
       
   133 
       
   134 <code language="lua">    SetAmmo(amLaserSight, 0, 0, 0, 1)
       
   135     SpawnUtilityCrate(0, 0, amLaserSight)</code>
       
   136 
       
   137 === `SpawnFakeAmmoCrate(x, y, explode, poison) ` ===
       
   138 Spawns a crate at the specified coordinates which looks exactly like a real ammo crate but contains not any ammo. It can be use useful for scripted events or to create a trap. If `x` and `y` are set to 0, the crate will spawn on a random position (but always on land).
       
   139 `explode` and `poison` are booleans.
       
   140 If `explode` is `true`, the crate will explode when collected.
       
   141 If `poison` is `true`, the collector will be poisoned.
       
   142 
       
   143 Example:
       
   144 
       
   145 <code language="lua">SpawnFakeAmmoCrate(500, 432, false, false) -- Spawns a fake ammo crate at the coordinates (500, 434) without explosion and poison.
       
   146 </code>
       
   147 
       
   148 === `SpawnFakeHealthCrate(x, y, explode, poison) ` ===
       
   149 Same as `SpawnFakeAmmoCrate`, except the crate will look like a health crate.
       
   150 
       
   151 === `SpawnFakeUtilityCrate(x, y, explode, poison) ` ===
       
   152 Same as `SpawnFakeAmmoCrate`, except the crate will look like an utility crate.
       
   153 
       
   154 == Functions to get and set gear properties ==
       
   155 
       
   156 === `GetGearType(gearUid)` ===
       
   157 This function returns the [GearTypes gear type] for the specified gear, if it exists.  If it doesn't exist, `nil` is returned.
       
   158 
       
   159 === `GetVisualGearType(vgUid)` (0.9.23) ===
       
   160 This function returns the [VisualGearTypes visual gear type] for the specified visual gear, if it exists.  If it doesn't exist, `nil` is returned.
       
   161 
       
   162 === `GetState(gearUid)` ===
       
   163 Returns the state of the gear. The gear state is a bitmask which is built out of the variables as shown in [States].
       
   164 
       
   165 This function is usually used in combination with `band` to extract the truth value of a single flag. It is also used together with `SetState` and `bor` in order to activate a single flag.
       
   166 
       
   167 Examples:
       
   168 <code language="lua">
       
   169 local state = GetState(gear)
       
   170 --[[ Stores the full raw bitmask of gear in state. Usually
       
   171 useless on its own. ]]
       
   172 </code>
       
   173 
       
   174 <code language="lua">
       
   175 isDrowning = band(GetState(CurrentHedgehog),gstDrowning) ~= 0
       
   176 --[[ GetState(CurrentHedgehog) returns the state bitmask of
       
   177 CurrentHedgehog, gstDrowning is a bitmask where only the
       
   178 “drowning” bit is set. band does a bitwise AND on both, if
       
   179 it returns a non-zero value, the hedgehog is drowning.]]
       
   180 </code>
       
   181 
       
   182 <code language="lua">
       
   183 SetState(CurrentHedgehog, bor(GetState(CurrentHedgehog), gstInvisible))
       
   184 --[[ first the state bitmask of CurrentHedgehog is bitwise ORed with
       
   185 the gstInvisible flag, thus making the bit responsible for
       
   186 invisiblity to become 1. Then the new bitmask is applied to
       
   187 CurrentHedgehog, thus making it invisible.]]
       
   188 </code>
       
   189 
       
   190 === `SetState(gearUid, state)` ===
       
   191 Sets the state of the specified gear to the specified `state`. This is a bitmask made out of the variables as seen in [States].
       
   192 
       
   193 This function is often used together with `GetState` and the bitmask utility functions `band` and `bnot` in order to manipulate a single flag.
       
   194 
       
   195 Examples:
       
   196 <code language="lua">
       
   197 SetState(CurrentHedgehog, bor(GetState(CurrentHedgehog), gstInvisible))
       
   198 --[[ first the state bitmask of CurrentHedgehog is bitwise ORed with
       
   199 the gstInvisible flag, thus making the bit responsible for
       
   200 invisiblity to become 1. Then the new bitmask is applied to
       
   201 CurrentHedgehog, thus making it invisible. ]]
       
   202 </code>
       
   203 
       
   204 <code language="lua">
       
   205 SetState(CurrentHedgehog, band(GetState(CurrentHedgehog), bnot(gstInvisible)))
       
   206 --[[ The reverse of the above: This function toggles CurrentHedgehog’s
       
   207 gstInvisible flag off, thus making it visible again. ]]
       
   208 </code>
       
   209 
       
   210 
       
   211 === `GetGearMessage(gearUid)` ===
       
   212 Returns the message of the gear. This is a bitmask built out of flags seen in [GearMessages].
       
   213 
       
   214 === `SetGearMessage(gearUid, message)` ===
       
   215 Sets the gear messages of the specified gear. `message` is a bitmask built out of flags seen in [GearMessages].
       
   216 
       
   217 === `GetTag(gearUid)` ===
       
   218 Returns the tag of the specified gear (by `gearUid`). 
       
   219 
       
   220 The `Tag` of a gear is just another arbitrary variable to hold the gear's state. The meaning of a tag depends on the gear type. For example, for `gtBall` gears, it specifies the ball color, for `gtAirAttack` gears (airplane) it specifies the direction of the plane, etc. See [GearTypes] for a full list. The returned value will be an integer.
       
   221 
       
   222 Note that the word “tag” here does _not_ refer to the name and health tags you see above hedgehogs, this is something different. 
       
   223 
       
   224 <code language="lua">
       
   225 -- This adds a ball (the one from the ballgun) at (123, 456):
       
   226 ball = AddGear(123, 456, gtBall, 0, 0, 0, 0)
       
   227 -- The tag of a ball defines its color. It will automatically chosen at random when created.
       
   228 colorTag = GetTag(ball)
       
   229 -- Now colorTag stores the tag of ball (in this case a number denoting its color)
       
   230 </code>
       
   231 
       
   232 The meaning of tags are described in [GearTypes].
       
   233 
       
   234 === `SetTag(gearUid, tag)` ===
       
   235 Sets the `Tag` value of the specified gear (by `gearUid`). The `Tag` value of a gear is simply an extra variable to modify misc. things. The meaning of a tag depends on the gear type. For example, for `gtBall` gears, it specifies the ball color, for `gtAirAttack` gears (airplane) it specifies the direction of the plane, etc. See [GearTypes] for a full list. `tag` has to be an integer.
       
   236 
       
   237 Note that the word “tag” here does _not_ refer to the name and health tags you see above hedgehogs, this is something different. 
       
   238 
       
   239 <code language="lua">
       
   240 -- This adds a ball (the one from the ballgun) at (123, 456):
       
   241 ball = AddGear(123, 456, gtBall, 0, 0, 0, 0)
       
   242 -- This sets the tag of the gear. For gtBall, the tag specified the color. “8” is the color white.
       
   243 SetTag(ball, 8) -- 
       
   244 </code>
       
   245 
       
   246 The meaning of tags are described in [GearTypes].
       
   247 
       
   248 === `GetTimer(gearUid)` ===
       
   249 Returns the timer of the gear. This is for example the time it takes for watermelon, mine, etc. to explode. This is also the time used to specify the blowtorch or RC plane time. See [GearTypes] for a full list.
       
   250 
       
   251 === `SetTimer(gearUid, timer)` ===
       
   252 Sets the timer of the specified gear. Also see `GetTimer`.
       
   253 
       
   254 === `GetHealth(gearUid)` ===
       
   255 Returns the health of the gear. Depending on the gear type, the gear's “health” can also refer to other things, see [GearTypes] for a full list.
       
   256 
       
   257 === `SetHealth(gearUid, health)` ===
       
   258 Sets the health of the specified gear. The “health” of a gear can refer to many things, depending on the gear type.
       
   259 
       
   260 *Hint*: If you like to increase the health of a hedgehog with nice visual effects, consider using `HealHog` instead.
       
   261 
       
   262 Use cases:
       
   263 
       
   264   * Setting the health of a hedgehog (`gtHedgehog`) to 99
       
   265   * Starting the RC Plane (`gtRCPlane`) with 10 bombs
       
   266   * Starting flying saucer (`gtJetpack`) with only 50% fuel
       
   267   * Setting all the mines (`gtMine`) to duds
       
   268   * And more!
       
   269 
       
   270 See [GearTypes] for a full description.
       
   271 
       
   272 <code language="lua">    function onGearAdd(gear)
       
   273        if (GetGearType(gear) == gtHedgehog) then
       
   274             -- Set hedgehog health to 99
       
   275             SetHealth(gear, 99)
       
   276        end
       
   277        if (GetGearType(gear) == gtRCPlaane) then
       
   278             -- Give the plane 10 bombs
       
   279             SetHealth(gear, 10)
       
   280        end
       
   281        if (GetGearType(gear) == gtJetpack) then
       
   282             -- Set fuel to 50% only
       
   283             SetHealth(gear, 1000)
       
   284        end
       
   285        if (GetGearType(gear) == gtMine) then
       
   286             -- Turn mine into dud
       
   287             SetHealth(gear, 0)
       
   288        end
       
   289     end</code>
       
   290 
       
   291 
       
   292 === `GetGearPos(gearUid)` ===
       
   293 Get the `Pos` value of the specified gear. `Pos` is just another arbitrary value to hold the state of the gear, such as `Tag` and `Health`, the meaning depends on the gear type. See [GearTypes] for the conrete meaning of a gear's `Pos` value. 
       
   294 
       
   295 *Important*: Pos is *not* related to the gear's position, use `GetGearPosition` for that.
       
   296 
       
   297 === `SetGearPos(gearUid, value)` ===
       
   298 Sets the `Pos` value (not the position!) of the specified gear to specified value. See `GetGearPos` for more information.
       
   299 
       
   300 === `GetGearCollisionMask(gearUid)` ===
       
   301 Returns the current collision mask of the given gear. See `SetGearCollisionMask` for an explanation of the mask.
       
   302 
       
   303 === `SetGearCollisionMask(gearUid, mask)` ===
       
   304 Set the collision mask of the given gear with `gearUid`.
       
   305 The collision mask defines with which gears and terrain types the gear can collide.
       
   306 
       
   307 `mask` is a number between `0x0000` and `0xFFFF` and used as a bitfield, which means you can combine these flags with `bor`. These are the available flags:
       
   308 
       
   309 || *Identifier* || *Collision with …* ||
       
   310 || `lfLandMask` || Terrain ||
       
   311 || `lfCurHogCrate` || Current hedgehog, and crates ||
       
   312 || `lfHHMask` || Any hedgehogs ||
       
   313 || `lfNotHHObjMask` || Objects, not hogs (e.g. mines, explosives) ||
       
   314 || `lfAllObjMask` || Hedgehogs and objects ||
       
   315 
       
   316 Beware, the collision mask is often set by the engine as well.
       
   317 
       
   318 Examples:
       
   319 <code language="lua">SetGearCollisionMask(gear, bnot(lfCurHogCrate))
       
   320 -- Ignore collision with current hedgehog</code>
       
   321 
       
   322 <code language="lua">SetGearCollisionMask(gear, 0xFFFF)
       
   323 -- Collide with everything</code>
       
   324 
       
   325 <code language="lua">SetGearCollisionMask(gear, lfAllObjMask)
       
   326 -- Collide with hedgehogs and objects</code>
       
   327 
       
   328 <code language="lua">SetGearCollisionMask(gear, 0x0000)
       
   329 -- Collide with nothing</code>
       
   330 
       
   331 There are actual more flags availbable, but they are not as useful for use in Lua and their constants have not been exposed to Lua. You can find the full range of flags in the engine source code (in Pascal):
       
   332 
       
   333 [https://hg.hedgewars.org/hedgewars/file/default/hedgewars/uConsts.pas#l112]
       
   334 
       
   335 === `GetGearRadius(gearUid)` ===
       
   336 Returns the `Radius` value for the specified gear. For most [GearTypes gear types] for “projectile” gears (like `gtShell` or `gtGrenade`), the radius refers to the gear's collision radius. This is an invisible circle around the center of the gear which is used for the collision checks. For a few gear types, its radius means something different, see [GearTypes] for a full list.
       
   337 
       
   338 To set the `Radius` value, use `SetGearValues`.
       
   339 
       
   340 === `GetFlightTime(gearUid)` ===
       
   341 Returns the `FlightTime` of the specified gear. The `FlightTime` is a gear varialbe used to store a general time interval. The precise meaning of the `FlightTime` depends on the gear type.
       
   342 
       
   343 For example: The `FlightTime` of a hedgehog (`gtHedgehog`) is the time since they last have stood on solid ground. For most projectile gear types (i.e. `gtShell`), it stores the time after it has been launched.
       
   344 
       
   345 === `SetFlightTime(gearUid, flighttime)` ===
       
   346 Sets the `FlightTime` of the given gear to `flighttime`. The meaning of `FlightTime` is explained in the section `GetFlightTime`.
       
   347 
       
   348 === `GetGearElasticity(gearUid) ` ===
       
   349 Returns the elasticity of the specified gear. The elasticity normally determines how strong the gear will bounce after collisions, where higher elasticity is for stronger bounces.
       
   350 
       
   351 This is also useful for determining if a hog is on a rope or not. If a hog is attached to a rope, or is busy firing one, the elasticity of the rope will be a non-zero number.
       
   352 
       
   353 === `SetGearElasticity(gearUid, Elasticity) ` ===
       
   354 Sets the elasticity of the specified gear. For most gears, the elasticity determines how strong the gear will bounce after collisions, where higher elasticity is for stronger bounces. Recommended are values between `0` and `9999`.
       
   355 
       
   356 === `GetGearFriction(gearUid) ` ===
       
   357 Returns the friction of the specified gear. The friction normally determines how well the gear will slide on terrain. Higher values are for increased sliding properties.
       
   358 
       
   359 === `SetGearFriction(gearUid, Friction) ` ===
       
   360 Sets the friction of the specified gear. The friction normally determines how well the gear will slide on terrain. Higher values are for increased sliding properties. `0` is for no sliding whatsoever, where `9999` is for very long slides, greater values are not recommended.
       
   361 
       
   362 === `GetGearTarget(gearUid, x, y) ` ===
       
   363 Returns the x and y coordinate of target-based weapons/utilities. 
       
   364 <b>Note:</b>: This can’t be used in `onGearAdd()` but must be called after gear creation. 
       
   365 
       
   366 === `SetGearTarget(gearUid, x, y)` ===
       
   367 Sets the x and y coordinate of target-based weapons/utilities.
       
   368 *Note*: This can’t be used in onGearAdd() but must be called after gear creation.
       
   369 
       
   370 === `GetGearValues(gearUid)` ===
       
   371 This returns a bunch of values associated with the gear, their meaning is often depending on the gear type and many values might be unused for certain gear types.
       
   372 
       
   373 This is returned (all variables are integers):
       
   374 
       
   375 `Angle, Power, WDTimer, Radius, Density, Karma, DirAngle, AdvBounce, ImpactSound, nImpactSounds, Tint, Damage, Boom`
       
   376 
       
   377 A rough description of some of the parameters:
       
   378 
       
   379  * `Radius`: Effect or collision radius, most of the time
       
   380  * `ImpactSound`: Sound it makes on a collision (see [Sounds])
       
   381  * `Tint`: Used by some gear types to determine its colorization. The color is in RGBA format.
       
   382  * `Boom`: Used by most gears to determine the damage dealt.
       
   383 
       
   384 Example:
       
   385 <code language="lua">
       
   386 -- Get all values in a single line of code:
       
   387 local Angle, Power, WDTimer, Radius, Density, Karma, DirAngle, AdvBounce, ImpactSound, nImpactSounds, Tint, Damage, Boom, Scale = GetGearValues(myGear)
       
   388 </code>
       
   389 
       
   390 === `SetGearValues(gearUid, Angle, Power, WDTimer, Radius, Density, Karma, DirAngle, AdvBounce, ImpactSound, ImpactSounds, Tint, Damage, Boom)` ===
       
   391 Sets various gear value for the specified gear (`gearUid`). The meaining of each value often depends on the gear type. See the documentation on !GetGearValues for a brief description of the gear values. If `gearUid` is invalid or the gear does not exist, nothing happens.
       
   392 
       
   393 Set `nil` for each value you do not want to change.
       
   394 
       
   395 Example:
       
   396 <code language="lua">
       
   397 -- Paints all RC planes into a white color
       
   398 function onGearAdd(gear)
       
   399     if GetGearType(gear) == gtRCPlane then
       
   400          SetGearValues(gear, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, 0xFFFFFFFF)
       
   401     end
       
   402 end
       
   403 </code>
       
   404 
       
   405 === `GetVisualGearValues(vgUid)` ===
       
   406 This returns the typically set visual gear values for the specified visual gear `vgUid`, useful if manipulating things like smoke, bubbles or circles. On success, it returns the following values:
       
   407 
       
   408 `X, Y, dX, dY, Angle, Frame, FrameTicks, State, Timer, Tint, Scale`
       
   409 
       
   410 The meaning of these values is the same as in `SetVisualGearValues`.
       
   411 
       
   412 If the visual gear does not exist, `nil` is returned. Always check the result for `nil` before you plug in the values anywhere.
       
   413 
       
   414 Most visual gears require little to no modification of parameters.
       
   415 
       
   416 Example:
       
   417 
       
   418 <code language="lua">-- Return visual gear values
       
   419 local X, Y, dX, dY, Angle, Frame, FrameTicks, State, Timer, Tint, Scale = GetVisualGearValues(vgUid)
       
   420 </code>
       
   421 
       
   422 === `SetVisualGearValues(vgUid, X, Y, dX, dY, Angle, Frame, !FrameTicks, State, Timer, Tint, Scale)` ===
       
   423 This allows manipulation of the internal state of the visual gear `vgUid`. If `vgUid` is invalid or the `vgUid` does not refer to an existing visual gear, the function does nothing. Thus, you can safely call this function even if you are not sure if the visual gear actually exists.
       
   424 
       
   425 All visual gear values are numbers. Each visual gear may be using these parameters differently, but the *usual* meaning of these is the following:
       
   426 
       
   427  * `X`, `Y`: Position
       
   428  * `dX`, `dY`: Speed along the X and Y axis
       
   429  * `Angle`: Current rotation
       
   430  * `Frame`: Image frame, if using a sprite sheet
       
   431  * `FrameTicks` is usually an animation counter
       
   432  * `State`: Helper value to save some internal state
       
   433  * `Timer`: Time in milliseconds until it expires
       
   434  * `Tint`: RGBA color
       
   435  * `Scale` is a scale factor (not used by all visual gears)
       
   436 
       
   437 Some visual gears interpret these values differently, just like normal gears. See [VisualGearTypes] for details.  Also, most visual gears are not using all possible values, while some values are just ignored.
       
   438 
       
   439 Note that most visual gears require little to no modification of their values.
       
   440 
       
   441 *NOTE*: *Never* use the visual gear's internal state to manipulate/store anything gameplay-related.  Visual gears are not safe for reliable storage and using them as that would lead to strange bugs.
       
   442 
       
   443 Example 1:
       
   444 
       
   445 <code language="lua">  -- set a circle to position 1000,1000 pulsing from opacity 20 to 200 (8%-78%), radius of 50, 3px thickness, bright red.
       
   446     SetVisualGearValues(circleUid, 1000,1000, 20, 200, 0, 0, 100, 50, 3, 0xff0000ff)</code>
       
   447 
       
   448 Only the first argument is required. Everything else is optional. Any such argument which is declared as `nil` will not overwrite the corresponding value of the visual gear.
       
   449 
       
   450 Example 2:
       
   451 
       
   452 <code language="lua">  -- set a visual gear to position 1000,1000
       
   453     SetVisualGearValues(circleUid, 1000, 1000)</code>
       
   454 <code language="lua">  -- set the tint of a visual gear to bright red.
       
   455     SetVisualGearValues(circleUid, nil, nil, nil, nil, nil, nil, nil, nil, nil, 0xff0000ff)</code>
       
   456     
       
   457 === `SetGearAIHints(gearUid, aiHint)` ===
       
   458 Set some behaviour hints for computer-controlled hedgehogs for any given gear with `gearUid`.
       
   459 
       
   460 Set `aiHint` to either of:
       
   461 
       
   462  * `aihUsualProcessing`: AI hogs treat this gear the usual way. This is the default.
       
   463  * `aihDoesntMatter`: AI hogs don't bother attacking this gear intentionally.
       
   464 
       
   465 Example:
       
   466 
       
   467 <code language="lua">
       
   468 SetGearAIHints(uselessHog, aihDoesntMatter)
       
   469 -- This makes AI hogs stop caring about attacking uselessHog</code>
       
   470 
       
   471 == Position and velocity ==
       
   472 === `GetGearPosition(gearUid)` ===
       
   473 Returns x,y coordinates for the specified gear. Not to be confused with `GetGearPos`.
       
   474 
       
   475 === `GetX(gearUid)` ===
       
   476 Returns x coordinate of the gear.
       
   477 
       
   478 === `GetY(gearUid)` ===
       
   479 Returns y coordinate of the gear.
       
   480 
       
   481 === `SetGearPosition(gearUid, x, y)` ===
       
   482 Places the specified gear exactly at the position (`x`,`y`). Not to be confused with `SetGearPos`.
       
   483 
       
   484 === `GetGearVelocity(gearUid)` ===
       
   485 Returns a tuple of dx,dy values for the specified gear.
       
   486 
       
   487 === `SetGearVelocity(gearUid, dx, dy)` ===
       
   488 Gives the specified gear the velocity of `dx`, `dy`.
       
   489 
       
   490 === `CopyPV(gearUid, gearUid)` ===
       
   491 This sets the position and velocity of the second gear to the first one.
       
   492 
       
   493 === `FindPlace(gearUid, fall, left, right[, tryHarder])` ===
       
   494 Finds a place for the specified gear between x=`left` and x=`right` and places it there. `tryHarder` is optional, setting it to `true`/`false` will determine whether the engine attempts to make additional passes, even attempting to place gears on top of each other.
       
   495 
       
   496 Example:
       
   497 
       
   498 <code language="lua">    gear = AddGear(...)
       
   499     FindPlace(gear, true, 0, LAND_WIDTH) -- places the gear randomly between 0 and LAND_WIDTH</code>
       
   500 
       
   501 == Hedgehog-specific functions ==
       
   502 === `GetHogName(gearUid)` ===
       
   503 Returns the name of the specified hedgehog gear.
       
   504 
       
   505 === `SetHogName(gearUid, name)` ===
       
   506 Sets the name of the specified hedgehog gear.
       
   507 
       
   508 === `GetHogTeamName(gearUid)` ===
       
   509 Returns the name of the specified gear’s team. `gearUid` can be a hedgehog or a grave.
       
   510 
       
   511 === `SetHogTeamName(gearUid, name)` ===
       
   512 Sets the team name of the specified gear. The gear can be a hedgehog or grave.
       
   513 
       
   514 === `GetHogClan(gearUid)` ===
       
   515 Returns the clan ID of the specified hedgehog gear.
       
   516 
       
   517 === `GetEffect(gearUid, effect)` ===
       
   518 Returns the state of given effect for the given hedgehog gear.
       
   519 
       
   520 See `SetEffect` for further details.
       
   521 
       
   522 === `SetEffect(gearUid, effect, effectState)` ===
       
   523 Sets the state for one of the effects `heInvulnerable, heResurrectable, hePoisoned, heResurrected, heFrozen` for the specified hedgehog gear.
       
   524 A value of 0 usually means the effect is disabled, values other than that indicate that it is enabled and in some cases specify e.g. the remaining time of that effect.
       
   525 
       
   526 || *`effect`* || *Description* || *`effectState`* ||
       
   527 || `heInvulnerable` || Wether hog is invulnerable || Any non-zero value turns on invulnerability. `0` turns it off. ||
       
   528 || `hePoisoned` || Poison damage, damages hog each turn. || Amount of damage per turn. Use `0` to disable poisoning. ||
       
   529 || `heResurrectable` || Whether to resurrect the hog on death || With a non-zero value, the hedgehog will be resurrected and teleported to a random location on death. `0` disables this. ||
       
   530 || `heResurrected` || Whether the hedgehog has been resurrected once. This is only a subtle graphical effect. || With a non-zero value, the hedgehog was resurrected, `0` otherwise. ||
       
   531 || `heFrozen` || Freeze level. Frozen hedgehogs skip turn, are heavy and take half damage || The hog is considered frozen if the value is `256` or higher, otherwise not. A number of `256` or higher denotes “how frozen” the hedgehog is, i.e. how long it takes to melt. The freezer sets this to `199999` initially. The value will be reduced by `50000` each round. Being hit by a flame reduces this number by `1000`. The values `0` to `255` are used for the freeze/melt animations. ||
       
   532 || `heArtillery` || If enabled, the hedgehog can't walk (since 0.9.24). || `0` = disabled. `1` = permanently enabled. `2` = temporarily enabled (used by sniper rifle between shots) ||
       
   533 
       
   534 Example (sets all bots poisoned with poison damage of 1):
       
   535 
       
   536 <code language="lua">    function onGearAdd(gear)
       
   537         if (GetGearType(gear) == gtHedgehog) and (GetHogLevel(gear) > 0) then
       
   538             SetEffect(gear, hePoisoned, 1)
       
   539         end
       
   540     end</code>
       
   541 
       
   542 === `GetHogHat(gearUid)` ===
       
   543 Returns the hat of the specified hedgehog gear.
       
   544 
       
   545 === `SetHogHat(gearUid, hat)` ===
       
   546 Sets the hat of the specified hedgehog gear.
       
   547 
       
   548 === `GetHogFlag(gearUid)` ===
       
   549 Returns the name of the flag of the team of the specified hedgehog gear.
       
   550 
       
   551 === `GetHogFort(gearUid)` (0.9.23) ===
       
   552 Returns the name of the fort of the team of the specified hedgehog gear.
       
   553 
       
   554 === `GetHogGrave(gearUid)` ===
       
   555 Returns the name of the grave of the team of the specified hedgehog gear.
       
   556 
       
   557 === `GetHogVoicepack(gearUid)` ===
       
   558 Returns the name of the voicepack of the team of the specified hedgehog gear.
       
   559 
       
   560 === `GetAmmoCount(gearUid, ammoType)` ===
       
   561 Returns the ammo count of the specified ammo type for the specified hedgehog gear. If infinite, returns `AMMO_INFINITE`.
       
   562 
       
   563 === `GetAmmoTimer(gearUid, ammoType)` (0.9.25) ===
       
   564 Returns the currently configured ammo timer (in milliseconds) for the given hedgehog gear and specified ammo type. This is the timer which is set by the player by using the timer keys (1-5). For ammo types for which the timer cannot be changed, `nil` is returned.
       
   565 
       
   566 Example:
       
   567 <code lang="lua">GetAmmoTimer(CurrentHedgehog, amGrenade)
       
   568 -- May return 1000, 2000, 3000, 4000 or 5000</code>
       
   569 
       
   570 === `GetHogLevel(gearUid)` ===
       
   571 Returns the bot level ranging from `0` to `5`. `1` is the strongest bot level and `5` is the weakest one (this is the reverse of what players see). `0` is for human player.
       
   572 
       
   573 === `SetHogLevel(gearUid, level)` ===
       
   574 Sets the bot level from 0 to 5. `1` is the strongest bot level and `5` is the weakest one (this is the reverse of what players see). `0` means human player.
       
   575 
       
   576 === `HealHog(gearUid, healthBoost[, showMessage[, tint]])` (0.9.24) ===
       
   577 Convenience function to increase the health of a hedgehog with default visual effects.
       
   578 
       
   579 Specifically, this increases the health of the hedgehog gear with the given ID `gearUid` by `healthBoost`, displays some healing particles at the hedgehog and shows the health increae as a message. This is similar to the behavour after taking a health crate, or getting a health boost from vampirism.
       
   580 
       
   581 If `showMessage` is false, no message is shown. With `tint` you can set the RGBA color of the particles (default: `0x00FF00FF`).
       
   582 
       
   583 This function does not affect the poison state, however (see `SetEffect`).
       
   584 
       
   585 === `HogTurnLeft(gearUid, boolean)` ===
       
   586 Faces the specified hog left or right.
       
   587 
       
   588 Example:
       
   589 
       
   590 <code language="lua">    HogTurnLeft(CurrentHedgehog, true) -- turns CurrentHedgehog left 
       
   591     HogTurnLeft(CurrentHedgehog, false) -- turns CurrentHedgehog right</code>
       
   592 
       
   593 === `IsHogHidden(gearUid)` (0.9.25) ===
       
   594 Returns true if hedgehog gear is hidden (e.g. via `HideHog` or the !TimeBox), false if it isn't, nil if that hedgehog never existed.
       
   595 
       
   596 === `HideHog(gearUid)` ===
       
   597 Removes a hedgehog from the map. The hidden hedgehog can be restored with `RestoreHog(gearUid)`. Since 0.9.23, returns `true` on success and `false` on failure (if gear does not exist / hog is already hidden).
       
   598 
       
   599 Example: 
       
   600 
       
   601 <code language="lua">    gear = AddGear(...)
       
   602      HideHog(gear) -- Hide the newly created gear.</code>
       
   603 
       
   604 === `RestoreHog(gearUid)` ===
       
   605 Restores a previously hidden hedgehog.  Nothing happens if the hedgehog does not exist or is not hidden.
       
   606 
       
   607 Example: 
       
   608 
       
   609 <code language="lua">    gear = AddGear(...)
       
   610      HideHog(gear) -- Hide the newly created gear.
       
   611      RestoreHog(gear) -- Restore the newly hidden gear.</code>
       
   612 
       
   613 === `IsHogLocal(gearUid)` (0.9.23) ===
       
   614 Returns `true` if the specified hedgehog gear is controlled by a human player on the computer on which Hedgewars runs on (i.e. not over a computer over the network). Also returns `true` if the hog is a member of any of the local clans. Returns `false` otherwise. Returns `nil` if `gearUid` is invalid.
       
   615 
       
   616 This is perfect to hide certain captions like weapon messages from enemy eyes.
       
   617 
       
   618 == Functions for gear actions ==
       
   619 === `GetFollowGear()` ===
       
   620 Returns the uid of the gear that is currently being followed.
       
   621 
       
   622 === `FollowGear(gearUid)` ===
       
   623 Makes the game client follow the specifiec gear (if it exists). Does not work for visual gears.
       
   624 
       
   625 === `HogSay(gearUid, text, manner [,vgState])` ===
       
   626 Makes the specified gear say, think, or shout some text in a comic-style speech or thought bubble. `gearUid` is _not_ limited to hedgehogs, altough the function name suggests otherwise.
       
   627 
       
   628 The `manner` parameter specifies the type of the bubble and can have one of these values:
       
   629 
       
   630 || *Value of `manner`* || *Looks* ||
       
   631 || `SAY_THINK` || Thought bubble ||
       
   632 || `SAY_SAY` || Speech bubble ||
       
   633 || `SAY_SHOUT` || Exclamatory bubble (denotes shouting) ||
       
   634 
       
   635 There is a optional 4th parameter `vgState`, it defines wheather the speechbubble is drawn fully opaque or semi-transparent. The value `0` is the default value.
       
   636 
       
   637 || *Value of `vgState`* || *Effect* ||
       
   638 || `0` || If the specified gear is a hedgehog, and it’s the turn of the hedgehog’s team, the bubble is drawn fully opaque.<br>If the gear is a hedgehog, and it’s another team’s turn, the bubble is drawn translucent.<br>If the gear is not a hedgehog, the bubble is drawn fully opaque. ||
       
   639 || `1` || The bubble is drawn translucent. ||
       
   640 || `2` || The bubble is drawn fully opaque. ||
       
   641 
       
   642 Examples:
       
   643 
       
   644 <code language="lua">HogSay(CurrentHedgehog, "I wonder what to do …", SAY_THINK) -- thought bubble with text “I wonder what to do …”</code>
       
   645 <code language="lua">HogSay(CurrentHedgehog, "I'm hungry.", SAY_SAY) -- speech bubble with text “I’m hungry.”</code>
       
   646 <code language="lua">HogSay(CurrentHedgehog, "I smell CAKE!", SAY_SHOUT) -- exclamatory bubble with text “I smell CAKE!”</code>
       
   647 
       
   648 == Functions to delete gears ==
       
   649 === `DeleteGear(gearUid)` ===
       
   650 Deletes a gear.  If the specified gear did not exist, nothing happens.
       
   651 
       
   652 Example:
       
   653 
       
   654 <code language="lua">    gear = AddGear(...)
       
   655     DeleteGear(gear) -- Delete the newly created gear.</code>
       
   656 
       
   657 === `DeleteVisualGear(vgUid)` ===
       
   658 Deletes a visual gear.  If it does not exist, nothing happens. 
       
   659 
       
   660 Note, most visual gears delete themselves after a while.
       
   661 
       
   662 
       
   663 
       
   664 Example:
       
   665 
       
   666 <code language="lua">    vgear = AddVisualGear(...)
       
   667     DeleteVisualGear(vgear) -- Delete the newly created visual gear.</code>