</div><divclass="outer-block"id="Introduction"><h3>Introduction<aclass="top"href="#top">^top</a></h3><divclass="preamble"><p>Helper Utilities for a Multitude of Problems is a set of lightweight helpers
</div></div><divclass="outer-block"id="Modules"><h3>Modules<aclass="top"href="#top">^top</a></h3><divclass="preamble"><dl><dt><ahref="#hump.gamestate">hump.gamestate</a></dt><dd>A gamestate system.</dd><dt><ahref="#hump.timer">hump.timer</a></dt><dd>Delayed and time-limited function calls.</dd><dt><ahref="#hump.vector">hump.vector</a></dt><dd>2D vector math.</dd><dt><ahref="#hump.vector-light">hump.vector-light</a></dt><dd>Lightweight 2D vector math.</dd><dt><ahref="#hump.class">hump.class</a></dt><dd>Object oriented programming for Lua.</dd><dt><ahref="#hump.signal">hump.signal</a></dt><dd>Simple Signal/Slot (aka. Observer) implementation.</dd><dt><ahref="#hump.camera">hump.camera</a></dt><dd>A camera for LÖVE.</dd></dl>
</div><divclass="overview"><h4>Module overview</h4><dl><dt><ahref="#hump.gamestateCallbacks ">Callbacks </a></dt><dd>Gamestate Callbacks.</dd><dt><ahref="#hump.gamestatenew">new()</a></dt><dd>Create a new gamestate.</dd><dt><ahref="#hump.gamestateswitch">switch()</a></dt><dd>Switch to gamestate.</dd><dt><ahref="#hump.gamestate<callback>"><callback>()</a></dt><dd>Call function on active gamestate.</dd><dt><ahref="#hump.gamestateregisterEvents">registerEvents()</a></dt><dd>Automatically do all of the above when needed.</dd></dl></div><divclass="section-block"id="hump.gamestateCallbacks "><h4>Callbacks <aclass="top"href="#hump.gamestate">^top</a></h4><p>A gamestate can define all callbacks that LÖVE defines. In addition, there are
callbacks for initalizing, entering and leaving a state:</p>
<dl>
<dt><codeclass="lua">init()</code></dt>
<dd>Called once before entering the state. See <ahref="#hump.gamestateswitch"><codeclass="lua">switch()</code></a>.</dd><dt><codeclass="lua">enter(previous, ...)</code></dt>
<dd>Called when entering the state. See <ahref="#hump.gamestateswitch"><codeclass="lua">switch()</code></a>.</dd><dt><codeclass="lua">leave()</code></dt>
<dd>Called when leaving a state. See <ahref="#hump.gamestateswitch"><codeclass="lua">switch()</code></a>.</dd><dt><codeclass="lua">update()</code></dt>
<dd>Update the game state. Called every frame.</dd><dt><codeclass="lua">draw()</code></dt>
<dd>Draw on the screen. Called every frame.</dd><dt><codeclass="lua">focus()</code></dt>
<dd>Called if the window gets or looses focus.</dd><dt><codeclass="lua">keypressed()</code></dt>
<dd>Triggered when a key is pressed.</dd><dt><codeclass="lua">keyreleased()</code></dt>
<dd>Triggered when a key is released.</dd><dt><codeclass="lua">mousepressed()</code></dt>
<dd>Triggered when a mouse button is pressed.</dd><dt><codeclass="lua">mousereleased()</code></dt>
<dd>Triggered when a mouse button is released.</dd><dt><codeclass="lua">joystickpressed()</code></dt>
<dd>Triggered when a joystick button is pressed.</dd><dt><codeclass="lua">joystickreleased()</code></dt>
<dd>Triggered when a joystick button is released.</dd><dt><codeclass="lua">quit()</code></dt>
<dd>Called on quitting the game. Only called on the active gamestate.</dd></dl>
<p>When using <ahref="#hump.gamestateregisterEvents"><codeclass="lua">registerEvents()</code></a>, all these
callbacks will be called by the corresponding LÖVE callbacks and receive
receive the same arguments (e.g. <codeclass="lua">state:update(dt)</code> will be called by
</div><divclass="ref-block"id="hump.gamestatenew"><h4>function <spanclass="name">new</span><spanclass="arglist">()</span><aclass="top"href="#hump.gamestate">^top</a></h4><p><strong>Deprecated: Use the table constructor instead (see example)</strong></p>
<p>Declare a new gamestate (just an empty table). A gamestate can define several
</div></div><divclass="ref-block"id="hump.gamestateswitch"><h4>function <spanclass="name">switch</span><spanclass="arglist">(to, ...)</span><aclass="top"href="#hump.gamestate">^top</a></h4><p>Switch to a gamestate, with any additional arguments passed to the new state.</p>
</div></div><divclass="ref-block"id="hump.gamestate<callback>"><h4>function <spanclass="name"><callback></span><spanclass="arglist">(...)</span><aclass="top"href="#hump.gamestate">^top</a></h4><p>Calls a function on the current gamestate. Can be any function, but is intended to
be one of the <ahref="#hump.gamestateCallbacks">callbacks</a>. Mostly useful when not using
</div></div><divclass="ref-block"id="hump.gamestateregisterEvents"><h4>function <spanclass="name">registerEvents</span><spanclass="arglist">(callbacks)</span><aclass="top"href="#hump.gamestate">^top</a></h4><p>Overwrite love callbacks to call <codeclass="lua">Gamestate.update()</code>, <codeclass="lua">Gamestate.draw()</code>, etc.
automatically. love callbacks (e.g. <codeclass="lua">love.update()</code>) are still invoked.</p>
<p>This is by done by overwriting the love callbacks, e.g.:</p>
</div><divclass="overview"><h4>Module overview</h4><dl><dt><ahref="#hump.timernew">new()</a></dt><dd>Create new timer instance.</dd><dt><ahref="#hump.timeradd">add()</a></dt><dd>Schedule a function.</dd><dt><ahref="#hump.timeraddPeriodic">addPeriodic()</a></dt><dd>Add a periodic function.</dd><dt><ahref="#hump.timerdo_for">do_for()</a></dt><dd>Run a function for the next few seconds.</dd><dt><ahref="#hump.timercancel">cancel()</a></dt><dd>Cancel a scheduled function.</dd><dt><ahref="#hump.timerclear">clear()</a></dt><dd>Remove all timed and periodic functions.</dd><dt><ahref="#hump.timerupdate">update()</a></dt><dd>Update scheduled functions.</dd></dl></div><divclass="ref-block"id="hump.timernew"><h4>function <spanclass="name">new</span><spanclass="arglist">()</span><aclass="top"href="#hump.timer">^top</a></h4><p><strong>If you don't need multiple independent schedulers, you can use the
global/default timer (see examples).</strong></p>
<p>Creates a new timer instance that is independent of the global timer: It will
manage it's own list of scheduled functions and does not in any way affect the
the global timer. Likewise, the global timer does not affect timer instances.</p>
<p><strong>Note:</strong> Timer instances use the colon-notation (e.g. <codeclass="lua">instance:update(dt)</code>),
while the global timer uses the dot-notation (e.g. <codeclass="lua">Timer.update(dt)</code>).</p>
</div></div><divclass="ref-block"id="hump.timeradd"><h4>function <spanclass="name">add</span><spanclass="arglist">(delay, func)</span><aclass="top"href="#hump.timer">^top</a></h4><p>Schedule a function. The function will be executed after <codeclass="lua">delay</code> seconds have
elapsed, given that <codeclass="lua">update(dt)</code> is called every frame.</p>
<p><strong>Note:</strong> There is no guarantee that the delay will not be exceeded, it is only
guaranteed that the function will <em>not</em> be executed <em>before</em> the delay has
passed.</p>
<p><codeclass="lua">func</code> will receive itself as only parameter. This is useful to implement
periodic behavior (see the example).</p>
<divclass="arguments">Parameters:<dl>
<dt>number <codeclass="lua">delay</code></dt>
<dd>Number of seconds the function will be delayed.</dd><dt>function <codeclass="lua">func</code></dt>
<dd>The function to be delayed.</dd></dl>
</div><divclass="returns">Returns:<dl>
<dt>table</dt>
<dd>The timer handle.</dd></dl>
</div><divclass="example">Examples:<pre><codeclass="lua">-- grant the player 5 seconds of immortality
</div></div><divclass="ref-block"id="hump.timeraddPeriodic"><h4>function <spanclass="name">addPeriodic</span><spanclass="arglist">(delay, func)</span><aclass="top"href="#hump.timer">^top</a></h4><p>Add a function that will be called <codeclass="lua">count</code> times every <codeclass="lua">delay</code> seconds.</p>
<p>If <codeclass="lua">count</code> is omitted, the function will be called until it returns <codeclass="lua">false</code> or
<ahref="#hump.timercancel"><codeclass="lua">cancel(handle)</code></a> or <ahref="#hump.timerclear"><codeclass="lua">clear()</code></a> is
called.</p>
<divclass="arguments">Parameters:<dl>
<dt>number <codeclass="lua">delay</code></dt>
<dd>Number of seconds between two consecutive function calls.</dd><dt>function <codeclass="lua">func</code></dt>
<dd>The function to be called periodically.</dd><dt>number <codeclass="lua">count</code> (optional)</dt>
<dd>Number of times the function is to be called.</dd></dl>
</div><divclass="returns">Returns:<dl>
<dt>table</dt>
<dd>The timer handle. See also <ahref="#hump.timercancel"><codeclass="lua">cancel()</code></a>.</dd></dl>
</div><divclass="example">Examples:<pre><codeclass="lua">-- toggle light on and off every second
</div></div><divclass="ref-block"id="hump.timerdo_for"><h4>function <spanclass="name">do_for</span><spanclass="arglist">(delay, func, after)</span><aclass="top"href="#hump.timer">^top</a></h4><p>Run <codeclass="lua">func(dt)</code> for the next <codeclass="lua">delta</code> seconds. The function is called every time
<codeclass="lua">update(dt)</code> is called. Optionally run <codeclass="lua">after()</code> once <codeclass="lua">delta</code> seconds have
passed.</p>
<p><codeclass="lua">after()</code> will receive itself as only parameter.</p>
<p><strong>Note:</strong> You should not add new timers in <codeclass="lua">func(dt)</code>, as this can lead to random
crashes.</p>
<divclass="arguments">Parameters:<dl>
<dt>number <codeclass="lua">delta</code></dt>
<dd>Number of seconds the func will be called.</dd><dt>function <codeclass="lua">func</code></dt>
<dd>The function to be called on <codeclass="lua">update(dt)</code>.</dd><dt>function <codeclass="lua">after</code> (optional)</dt>
<dd>A function to be called after delta seconds.</dd></dl>
</div><divclass="returns">Returns:<dl>
<dt>table</dt>
<dd>The timer handle.</dd></dl>
</div><divclass="example">Examples:<pre><codeclass="lua">-- play an animation for 5 seconds
-- make sure the player is visible after three seconds
player.visible = true
player.isInvincible = false
end)
</code></pre>
</div></div><divclass="ref-block"id="hump.timercancel"><h4>function <spanclass="name">cancel</span><spanclass="arglist">(handle)</span><aclass="top"href="#hump.timer">^top</a></h4><p>Prevent a timer from being executed in the future.</p>
</div></div><divclass="ref-block"id="hump.timerclear"><h4>function <spanclass="name">clear</span><spanclass="arglist">()</span><aclass="top"href="#hump.timer">^top</a></h4><p>Remove all timed and periodic functions. Functions that have not yet been
</div></div><divclass="ref-block"id="hump.timerupdate"><h4>function <spanclass="name">update</span><spanclass="arglist">(dt)</span><aclass="top"href="#hump.timer">^top</a></h4><p>Update timers and execute functions if the deadline is reached. Use this in
<codeclass="lua">love.update(dt)</code>.</p>
<divclass="arguments">Parameters:<dl>
<dt>number <codeclass="lua">dt</code></dt>
<dd>Time that has passed since the last <codeclass="lua">update()</code>.</dd></dl>
</div><divclass="overview"><h4>Module overview</h4><dl><dt><ahref="#hump.vectorOperators ">Operators </a></dt><dd>Arithmetics and relations.</dd><dt><ahref="#hump.vectornew">new()</a></dt><dd>Create a new vector.</dd><dt><ahref="#hump.vectorisvector">isvector()</a></dt><dd>Test if value is a vector.</dd><dt><ahref="#hump.vectorvector:clone">vector:clone()</a></dt><dd>Copy a vector.</dd><dt><ahref="#hump.vectorvector:unpack">vector:unpack()</a></dt><dd>Extract coordinates.</dd><dt><ahref="#hump.vectorvector:permul">vector:permul()</a></dt><dd>Per element multiplication.</dd><dt><ahref="#hump.vectorvector:len">vector:len()</a></dt><dd>Get length.</dd><dt><ahref="#hump.vectorvector:len2">vector:len2()</a></dt><dd>Get squared length.</dd><dt><ahref="#hump.vectorvector:dist">vector:dist()</a></dt><dd>Distance to other vector.</dd><dt><ahref="#hump.vectorvector:normalized">vector:normalized()</a></dt><dd>Get normalized vector.</dd><dt><ahref="#hump.vectorvector:normalize_inplace">vector:normalize_inplace()</a></dt><dd>Normalize vector in-place.</dd><dt><ahref="#hump.vectorvector:rotated">vector:rotated()</a></dt><dd>Get rotated vector.</dd><dt><ahref="#hump.vectorvector:rotate_inplace">vector:rotate_inplace()</a></dt><dd>Rotate vector in-place.</dd><dt><ahref="#hump.vectorvector:perpendicular">vector:perpendicular()</a></dt><dd>Get perpendicular vector.</dd><dt><ahref="#hump.vectorvector:projectOn">vector:projectOn()</a></dt><dd>Get projection onto another vector.</dd><dt><ahref="#hump.vectorvector:mirrorOn">vector:mirrorOn()</a></dt><dd>Mirrors vector on other vector</dd><dt><ahref="#hump.vectorvector:cross">vector:cross()</a></dt><dd>Cross product of two vectors.</dd><dt><ahref="#hump.vectorvector:angleTo">vector:angleTo()</a></dt><dd>Measure angle between two vectors.</dd></dl></div><divclass="section-block"id="hump.vectorOperators "><h4>Operators <aclass="top"href="#hump.vector">^top</a></h4><p>Vector arithmetic is implemented by using <codeclass="lua">__add</code>, <codeclass="lua">__mul</code> and other
</div><divclass="ref-block"id="hump.vectornew"><h4>function <spanclass="name">new</span><spanclass="arglist">(x,y)</span><aclass="top"href="#hump.vector">^top</a></h4><p>Create a new vector.</p>
</div></div><divclass="ref-block"id="hump.vectorisvector"><h4>function <spanclass="name">isvector</span><spanclass="arglist">(v)</span><aclass="top"href="#hump.vector">^top</a></h4><p>Test whether a variable is a vector.</p>
<divclass="arguments">Parameters:<dl>
<dt>mixed <codeclass="lua">v</code></dt>
<dd>The variable to test.</dd></dl>
</div><divclass="returns">Returns:<dl>
<dt>boolean</dt>
<dd><codeclass="lua">true</code> if <codeclass="lua">v</code> is a vector, <codeclass="lua">false</code> otherwise</dd></dl>
</div><divclass="example">Example:<pre><codeclass="lua">if not vector.isvector(v) then
</div></div><divclass="ref-block"id="hump.vectorvector:clone"><h4>function <spanclass="name">vector:clone</span><spanclass="arglist">()</span><aclass="top"href="#hump.vector">^top</a></h4><p>Copy a vector. Simply assigning a vector a vector to a variable will create a
<em>reference</em>, so when modifying the vector referenced by the new variable would
</div></div><divclass="ref-block"id="hump.vectorvector:len"><h4>function <spanclass="name">vector:len</span><spanclass="arglist">()</span><aclass="top"href="#hump.vector">^top</a></h4><p>Get length of a vector, i.e. <codeclass="lua">math.sqrt(vec.x * vec.x + vec.y * vec.y)</code>.</p>
</div><divclass="example">Example:<pre><codeclass="lua">distance = (a - b):len()
</code></pre>
</div></div><divclass="ref-block"id="hump.vectorvector:len2"><h4>function <spanclass="name">vector:len2</span><spanclass="arglist">()</span><aclass="top"href="#hump.vector">^top</a></h4><p>Get squared length of a vector, i.e. <codeclass="lua">vec.x * vec.x + vec.y * vec.y</code>.</p>
</div></div><divclass="ref-block"id="hump.vectorvector:dist"><h4>function <spanclass="name">vector:dist</span><spanclass="arglist">(other)</span><aclass="top"href="#hump.vector">^top</a></h4><p>Get distance of two vectors. The same as <codeclass="lua">(a - b):len()</code>.</p>
<divclass="arguments">Parameters:<dl>
<dt>vector <codeclass="lua">other</code></dt>
<dd>Other vector to measure the distance to.</dd></dl>
</div><divclass="returns">Returns:<dl>
<dt>number</dt>
<dd>The distance of the vectors.</dd></dl>
</div><divclass="example">Example:<pre><codeclass="lua">-- get closest vertex to a given vector
</div></div><divclass="ref-block"id="hump.vectorvector:normalized"><h4>function <spanclass="name">vector:normalized</span><spanclass="arglist">()</span><aclass="top"href="#hump.vector">^top</a></h4><p>Get normalized vector, i.e. a vector with the same direction as the input
vector, but with length 1.</p>
<p>This does not change the input vector, but creates a new vector.</p>
</div></div><divclass="ref-block"id="hump.vectorvector:normalize_inplace"><h4>function <spanclass="name">vector:normalize_inplace</span><spanclass="arglist">()</span><aclass="top"href="#hump.vector">^top</a></h4><p>Normalize a vector, i.e. make the vector unit length. Great to use on
intermediate results.</p>
<p><strong>This modifies the vector. If in doubt, use
</div></div><divclass="ref-block"id="hump.vectorvector:rotated"><h4>function <spanclass="name">vector:rotated</span><spanclass="arglist">(angle)</span><aclass="top"href="#hump.vector">^top</a></h4><p>Get a rotated vector.</p>
<p>This does not change the input vector, but creates a new vector.</p>
<divclass="arguments">Parameters:<dl>
<dt>number <codeclass="lua">angle</code></dt>
<dd>Rotation angle in radians.</dd></dl>
</div><divclass="returns">Returns:<dl>
<dt>vector</dt>
<dd>The rotated vector</dd></dl>
</div><divclass="example">Example:<pre><codeclass="lua">-- approximate a circle
</div></div><divclass="ref-block"id="hump.vectorvector:rotate_inplace"><h4>function <spanclass="name">vector:rotate_inplace</span><spanclass="arglist">(angle)</span><aclass="top"href="#hump.vector">^top</a></h4><p>Rotate a vector in-place. Great to use on intermediate results.</p>
<p><strong>This modifies the vector. If in doubt, use
</div></div><divclass="ref-block"id="hump.vectorvector:perpendicular"><h4>function <spanclass="name">vector:perpendicular</span><spanclass="arglist">()</span><aclass="top"href="#hump.vector">^top</a></h4><p>Quick rotation by 90°. Creates a new vector. The same (but faster) as
</div></div><divclass="ref-block"id="hump.vectorvector:projectOn"><h4>function <spanclass="name">vector:projectOn</span><spanclass="arglist">(v)</span><aclass="top"href="#hump.vector">^top</a></h4><p>Project vector onto another vector (see sketch).</p>
</div></div><divclass="ref-block"id="hump.vectorvector:mirrorOn"><h4>function <spanclass="name">vector:mirrorOn</span><spanclass="arglist">(v)</span><aclass="top"href="#hump.vector">^top</a></h4><p>Mirrors vector on the axis defined by the other vector.</p>
</div></div><divclass="ref-block"id="hump.vectorvector:cross"><h4>function <spanclass="name">vector:cross</span><spanclass="arglist">(other)</span><aclass="top"href="#hump.vector">^top</a></h4><p>Get cross product of both vectors. Equals the area of the parallelogram spanned
by both vectors.</p>
<divclass="arguments">Parameters:<dl>
<dt>vector <codeclass="lua">other</code></dt>
<dd>Vector to compute the cross product with.</dd></dl>
</div></div><divclass="ref-block"id="hump.vectorvector:angleTo"><h4>function <spanclass="name">vector:angleTo</span><spanclass="arglist">(other)</span><aclass="top"href="#hump.vector">^top</a></h4><p>Measures the angle between two vectors. If <codeclass="lua">other</code> is omitted it defaults
to the vector <codeclass="lua">(0,0)</code>, i.e. the function returns the angle to the coordinate
</div><divclass="overview"><h4>Module overview</h4><dl><dt><ahref="#hump.vector-lightstr">str()</a></dt><dd>String representation.</dd><dt><ahref="#hump.vector-lightmul">mul()</a></dt><dd>Product of a vector and a scalar.</dd><dt><ahref="#hump.vector-lightdiv">div()</a></dt><dd>Product of a vector and the inverse of a scalar.</dd><dt><ahref="#hump.vector-lightadd">add()</a></dt><dd>Sum of two vectors.</dd><dt><ahref="#hump.vector-lightsub">sub()</a></dt><dd>Difference of two vectors.</dd><dt><ahref="#hump.vector-lightpermul">permul()</a></dt><dd>Per element multiplication.</dd><dt><ahref="#hump.vector-lightdot">dot()</a></dt><dd>Dot product.</dd><dt><ahref="#hump.vector-lightcross">cross()</a></dt><dd>Cross product.</dd><dt><ahref="#hump.vector-lighteq">eq()</a></dt><dd>Equality.</dd><dt><ahref="#hump.vector-lightle">le()</a></dt><dd>Partial lexical order.</dd><dt><ahref="#hump.vector-lightlt">lt()</a></dt><dd>Strict lexical order.</dd><dt><ahref="#hump.vector-lightlen">len()</a></dt><dd>Get length.</dd><dt><ahref="#hump.vector-lightlen2">len2()</a></dt><dd>Get squared length.</dd><dt><ahref="#hump.vector-lightdist">dist()</a></dt><dd>Distance of two points.</dd><dt><ahref="#hump.vector-lightdist2">dist2()</a></dt><dd>Squared distance of two points.</dd><dt><ahref="#hump.vector-lightnormalize">normalize()</a></dt><dd>Normalize vector.</dd><dt><ahref="#hump.vector-lightrotate">rotate()</a></dt><dd>Rotate vector.</dd><dt><ahref="#hump.vector-lightperpendicular">perpendicular()</a></dt><dd>Get perpendicular vector.</dd><dt><ahref="#hump.vector-lightproject">project()</a></dt><dd>Project vector onto another vector.</dd><dt><ahref="#hump.vector-lightmirror">mirror()</a></dt><dd>Mirror vector on other vector.</dd><dt><ahref="#hump.vector-lightangleTo">angleTo()</a></dt><dd>Measure angle between two vectors.</dd></dl></div><divclass="ref-block"id="hump.vector-lightstr"><h4>function <spanclass="name">str</span><spanclass="arglist">(x,y)</span><aclass="top"href="#hump.vector-light">^top</a></h4><p>Transforms a vector to a string of the form <codeclass="lua">(x,y)</code>.</p>
</div></div><divclass="ref-block"id="hump.vector-lightmul"><h4>function <spanclass="name">mul</span><spanclass="arglist">(s, x,y)</span><aclass="top"href="#hump.vector-light">^top</a></h4><p>Computes <codeclass="lua">x*s,y*s</code>. The order of arguments is chosen so that it's possible to
</div></div><divclass="ref-block"id="hump.vector-lightdiv"><h4>function <spanclass="name">div</span><spanclass="arglist">(s, x,y)</span><aclass="top"href="#hump.vector-light">^top</a></h4><p>Computes <codeclass="lua">x/s,y/s</code>. The order of arguments is chosen so that it's possible to
</div></div><divclass="ref-block"id="hump.vector-lightadd"><h4>function <spanclass="name">add</span><spanclass="arglist">(x1,y1, x2,y2)</span><aclass="top"href="#hump.vector-light">^top</a></h4><p>Computes the sum (<codeclass="lua">x1+x2,y1+y2</code>) of two vectors. Meant to be used in
</div></div><divclass="ref-block"id="hump.vector-lightsub"><h4>function <spanclass="name">sub</span><spanclass="arglist">(x1,y1, x2,y2)</span><aclass="top"href="#hump.vector-light">^top</a></h4><p>Computes the difference (<codeclass="lua">x1-x2,y1-y2</code>) of two vectors. Meant to be used in
</div></div><divclass="ref-block"id="hump.vector-lightdot"><h4>function <spanclass="name">dot</span><spanclass="arglist">(x1,y1, x2,y2)</span><aclass="top"href="#hump.vector-light">^top</a></h4><p>Computes the <ahref="http://en.wikipedia.org/wiki/Dot_product">dot product</a> of two
</div></div><divclass="ref-block"id="hump.vector-lightcross"><h4>function <spanclass="name">cross</span><spanclass="arglist">(x1,y1, x2,y2)</span><aclass="top"href="#hump.vector-light">^top</a></h4><p>Computes the <ahref="http://en.wikipedia.org/wiki/Cross_product">cross product</a> of two
</div></div><divclass="ref-block"id="hump.vector-lighteq"><h4>function <spanclass="name">eq</span><spanclass="arglist">(x1,y1, x2,y2)</span><aclass="top"href="#hump.vector-light">^top</a></h4><p>Test for equality.</p>
<dd><codeclass="lua">x1 < x2 or (x1 == x2) and y1 <= y2</code></dd></dl>
</div><divclass="example">Example:<pre><codeclass="lua">if vector.lt(x1,y1, x2,y2) then be.happy() end
</code></pre>
</div></div><divclass="ref-block"id="hump.vector-lightlen"><h4>function <spanclass="name">len</span><spanclass="arglist">(x,y)</span><aclass="top"href="#hump.vector-light">^top</a></h4><p>Get length of a vector, i.e. <codeclass="lua">math.sqrt(x*x + y*y)</code>.</p>
</div></div><divclass="ref-block"id="hump.vector-lightlen2"><h4>function <spanclass="name">len2</span><spanclass="arglist">(x,y)</span><aclass="top"href="#hump.vector-light">^top</a></h4><p>Get squared length of a vector, i.e. <codeclass="lua">x*x + y*y</code>.</p>
<divclass="arguments">Parameters:<dl>
<dt>numbers <codeclass="lua">x,y</code></dt>
<dd>The vector.</dd></dl>
</div><divclass="returns">Returns:<dl>
<dt>number</dt>
<dd>Squared length of the vector.</dd></dl>
</div><divclass="example">Example:<pre><codeclass="lua">-- get closest vertex to a given vector
</div></div><divclass="ref-block"id="hump.vector-lightdist"><h4>function <spanclass="name">dist</span><spanclass="arglist">(x1,y1, x2,y2)</span><aclass="top"href="#hump.vector-light">^top</a></h4><p>Get distance of two points. The same as <codeclass="lua">vector.len(x1-x2, y1-y2)</code>.</p>
</div></div><divclass="ref-block"id="hump.vector-lightdist2"><h4>function <spanclass="name">dist2</span><spanclass="arglist">(x1,y1, x2,y2)</span><aclass="top"href="#hump.vector-light">^top</a></h4><p>Get squared distance of two points. The same as <codeclass="lua">vector.len2(x1-x2, y1-y2)</code>.</p>
</div></div><divclass="ref-block"id="hump.vector-lightnormalize"><h4>function <spanclass="name">normalize</span><spanclass="arglist">(x,y)</span><aclass="top"href="#hump.vector-light">^top</a></h4><pre><codeclass="lua">Get normalized vector, i.e. a vector with the same direction as the input
vector, but with length 1.
</code></pre>
<divclass="arguments">Parameters:<dl>
<dt>numbers <codeclass="lua">x,y</code></dt>
<dd>The vector.</dd></dl>
</div><divclass="returns">Returns:<dl>
<dt>numbers</dt>
<dd>Vector with same direction as the input vector, but length 1.</dd></dl>
</div></div><divclass="ref-block"id="hump.vector-lightperpendicular"><h4>function <spanclass="name">perpendicular</span><spanclass="arglist">(x,y)</span><aclass="top"href="#hump.vector-light">^top</a></h4><p>Quick rotation by 90°. The same (but faster) as <codeclass="lua">vector.rotate(math.pi/2, x,y)</code>.</p>
<divclass="arguments">Parameters:<dl>
<dt>numbers <codeclass="lua">x,y</code></dt>
<dd>The vector.</dd></dl>
</div><divclass="returns">Returns:<dl>
<dt>numbers</dt>
<dd>A vector perpendicular to the input vector</dd></dl>
</div></div><divclass="ref-block"id="hump.vector-lightmirror"><h4>function <spanclass="name">mirror</span><spanclass="arglist">(x,y, u,v)</span><aclass="top"href="#hump.vector-light">^top</a></h4><p>Mirrors vector on the axis defined by the other vector.</p>
<divclass="arguments">Parameters:<dl>
<dt>numbers <codeclass="lua">x,y</code></dt>
<dd>The vector to mirror.</dd><dt>numbers <codeclass="lua">u,v</code></dt>
</div></div><divclass="ref-block"id="hump.vector-lightangleTo"><h4>function <spanclass="name">angleTo</span><spanclass="arglist">(ox,y, u,v)</span><aclass="top"href="#hump.vector-light">^top</a></h4><p>Measures the angle between two vectors. <codeclass="lua">u</code> and <codeclass="lua">v</code> default to <codeclass="lua">0</code> if omitted,
i.e. the function returns the angle to the coordinate system.</p>
<divclass="arguments">Parameters:<dl>
<dt>numbers <codeclass="lua">x,y</code></dt>
<dd>Vector to measure the angle.</dd><dt>numbers <codeclass="lua">u,v</code> (optional)</dt>
</div><divclass="overview"><h4>Module overview</h4><dl><dt><ahref="#hump.classnew">new()</a></dt><dd>Declare a new class.</dd><dt><ahref="#hump.classclass.init">class.init()</a></dt><dd>Call class constructor.</dd><dt><ahref="#hump.classclass:include">class:include()</a></dt><dd>Explicit class inheritance/mixin support.</dd><dt><ahref="#hump.classclass:clone">class:clone()</a></dt><dd>Clone class/prototype support.</dd><dt><ahref="#hump.classCaveats ">Caveats </a></dt><dd>Common gotchas.</dd></dl></div><divclass="ref-block"id="hump.classnew"><h4>function <spanclass="name">new</span><spanclass="arglist">{init = constructor, __includes = parents, ...}</span><aclass="top"href="#hump.class">^top</a></h4><p>Declare a new class.</p>
<p><codeclass="lua">init()</code> will receive the new object instance as first argument. Any other
arguments will also be forwarded (see examples), i.e. <codeclass="lua">init()</code> has the
<dd>Class constructor. Can be accessed with theclass.init(object, ...)</dd><dt>class <codeclass="lua">or table of classes parents</code> (optional)</dt>
<dd>Classes to inherit from. Can either be a single class or a table of classes</dd><dt>mixed <codeclass="lua">...</code> (optional)</dt>
<dd>Any other fields or methods common to all instances of this class.</dd></dl>
print(one.foo, two.foo, three.foo) --> prints 'foo foo foo'
one.foo = 'bar' -- overwrite/specify for instance `one' only
print(one.foo, two.foo, three.foo) --> prints 'bar foo foo'
A.foo = 'baz' -- overwrite for all instances without specification
print(one.foo, two.foo, three.foo) --> prints 'bar baz baz'
</code></pre>
</div></div><divclass="ref-block"id="hump.classclass.init"><h4>function <spanclass="name">class.init</span><spanclass="arglist">(object, ...)</span><aclass="top"href="#hump.class">^top</a></h4><p>Calls class constructor of a class on an object.</p>
<p>Derived classes should use this function their constructors to initialize the
</div></div><divclass="ref-block"id="hump.classclass:include"><h4>function <spanclass="name">class:include</span><spanclass="arglist">(other)</span><aclass="top"href="#hump.class">^top</a></h4><p>Inherit functions and variables of another class, but if they are not already
defined. This is done by (deeply) copying the functions and variables over to
print(a.foo, b.foo) -- prints 'bar nothing to see here...'
b.baz() -- prints 'baz'
b.bar.one = 10 -- changes only values in b
print(a.bar.one, b.bar.one) -- prints '1 10'
</code></pre>
</div></div><divclass="ref-block"id="hump.classclass:clone"><h4>function <spanclass="name">class:clone</span><spanclass="arglist">()</span><aclass="top"href="#hump.class">^top</a></h4><p>Create a clone/deep copy of the class.</p>
<p><strong>Note:</strong> You can use <codeclass="lua">Class.clone(a)</code> to create a deep copy of any table
</div></div><divclass="section-block"id="hump.classCaveats "><h4>Caveats <aclass="top"href="#hump.class">^top</a></h4><p>Be careful when using metamethods like <codeclass="lua">__add</code> or <codeclass="lua">__mul</code>: If subclass inherits
those methods from a superclass, but does not overwrite them, the result of the
operation may be of the type superclass. Consider the following:</p>
</div><divclass="overview"><h4>Module overview</h4><dl><dt><ahref="#hump.signalnew">new()</a></dt><dd>Create a new signal registry</dd><dt><ahref="#hump.signalregister">register()</a></dt><dd>Register function with signal.</dd><dt><ahref="#hump.signalemit">emit()</a></dt><dd>Call all functions bound to a signal.</dd><dt><ahref="#hump.signalremove">remove()</a></dt><dd>Remove functions from registry. </dd><dt><ahref="#hump.signalclear">clear()</a></dt><dd>Clears a signal registry.</dd><dt><ahref="#hump.signalemit_pattern">emit_pattern()</a></dt><dd>Emits signals matching a pattern.</dd><dt><ahref="#hump.signalremove_pattern">remove_pattern()</a></dt><dd>Remove functions from signals matching a pattern.</dd><dt><ahref="#hump.signalclear_pattern">clear_pattern()</a></dt><dd>Clears signal registry matching a pattern.</dd></dl></div><divclass="ref-block"id="hump.signalnew"><h4>function <spanclass="name">new</span><spanclass="arglist">()</span><aclass="top"href="#hump.signal">^top</a></h4><p><strong>If you don't need multiple independent registries, you can use the
global/default registry (see examples).</strong></p>
<p>Creates a new signal registry that is independent of the default registry: It
will manage it's own list of signals and does not in any way affect the the
global registry. Likewise, the global registry does not affect the instance.</p>
<p><strong>Note:</strong> Independent registries use the colon-notation (e.g.
<codeclass="lua">instance:emit("foo")</code>), while the global registry uses the dot-notation (e.g.
</div></div><divclass="ref-block"id="hump.signalregister"><h4>function <spanclass="name">register</span><spanclass="arglist">(s, f)</span><aclass="top"href="#hump.signal">^top</a></h4><p>Registers a function <codeclass="lua">f</code> to be called when signal <codeclass="lua">s</code> is emitted.</p>
<divclass="arguments">Parameters:<dl>
<dt>string <codeclass="lua">s</code></dt>
<dd>The signal identifier.</dd><dt>function <codeclass="lua">f</code></dt>
<dd>The function to register.</dd></dl>
</div><divclass="returns">Returns:<dl>
<dt>function</dt>
<dd>A function handle to use in <ahref="#hump.signalremove"><codeclass="lua">remove()</code></a>.</dd></dl>
</div></div><divclass="ref-block"id="hump.signalemit"><h4>function <spanclass="name">emit</span><spanclass="arglist">(s, ...)</span><aclass="top"href="#hump.signal">^top</a></h4><p>Calls all functions bound to signal <codeclass="lua">s</code> with the supplied arguments.</p>
<divclass="arguments">Parameters:<dl>
<dt>string <codeclass="lua">s</code></dt>
<dd>The signal identifier.</dd><dt>mixed <codeclass="lua">...</code> (optional)</dt>
<dd>Arguments to pass to the bound functions.</dd></dl>
</div></div><divclass="ref-block"id="hump.signalremove"><h4>function <spanclass="name">remove</span><spanclass="arglist">(s, ...)</span><aclass="top"href="#hump.signal">^top</a></h4><p>Unbinds (removes) functions from signal <codeclass="lua">s</code>.</p>
<divclass="arguments">Parameters:<dl>
<dt>string <codeclass="lua">s</code></dt>
<dd>The signal identifier.</dd><dt>functions <codeclass="lua">...</code></dt>
<dd>Functions to unbind from the signal.</dd></dl>
</div></div><divclass="ref-block"id="hump.signalclear"><h4>function <spanclass="name">clear</span><spanclass="arglist">(s)</span><aclass="top"href="#hump.signal">^top</a></h4><p>Removes all functions from signal <codeclass="lua">s</code>.</p>
</div></div><divclass="ref-block"id="hump.signalemit_pattern"><h4>function <spanclass="name">emit_pattern</span><spanclass="arglist">(p, ...)</span><aclass="top"href="#hump.signal">^top</a></h4><p>Emits all signals matching a <ahref="http://www.lua.org/manual/5.1/manual.html#5.4.1">string pattern</a>.</p>
<divclass="arguments">Parameters:<dl>
<dt>string <codeclass="lua">p</code></dt>
<dd>The signal identifier pattern.</dd><dt>mixed <codeclass="lua">...</code> (optional)</dt>
<dd>Arguments to pass to the bound functions.</dd></dl>
</div></div><divclass="ref-block"id="hump.signalremove_pattern"><h4>function <spanclass="name">remove_pattern</span><spanclass="arglist">(p, ...)</span><aclass="top"href="#hump.signal">^top</a></h4><p>Removes functions from all signals matching a <ahref="http://www.lua.org/manual/5.1/manual.html#5.4.1">string pattern</a>.</p>
<divclass="arguments">Parameters:<dl>
<dt>string <codeclass="lua">p</code></dt>
<dd>The signal identifier pattern.</dd><dt>functions <codeclass="lua">...</code></dt>
<dd>Functions to unbind from the signals.</dd></dl>
</div></div><divclass="ref-block"id="hump.signalclear_pattern"><h4>function <spanclass="name">clear_pattern</span><spanclass="arglist">(p)</span><aclass="top"href="#hump.signal">^top</a></h4><p>Removes <em>all</em> functions from all signals matching a <ahref="http://www.lua.org/manual/5.1/manual.html#5.4.1">string pattern</a>.</p>
</div><divclass="overview"><h4>Module overview</h4><dl><dt><ahref="#hump.cameranew">new()</a></dt><dd>Create a new camera.</dd><dt><ahref="#hump.cameracamera:move">camera:move()</a></dt><dd>Move camera.</dd><dt><ahref="#hump.cameracamera:lookAt">camera:lookAt()</a></dt><dd>Move camera to position.</dd><dt><ahref="#hump.cameracamera:pos">camera:pos()</a></dt><dd>Get camera position.</dd><dt><ahref="#hump.cameracamera:rotate">camera:rotate()</a></dt><dd>Rotate camera.</dd><dt><ahref="#hump.cameracamera:rotateTo">camera:rotateTo()</a></dt><dd>Set camera rotation.</dd><dt><ahref="#hump.cameracamera:zoom">camera:zoom()</a></dt><dd>Change zoom.</dd><dt><ahref="#hump.cameracamera:zoomTo">camera:zoomTo()</a></dt><dd>Set zoom.</dd><dt><ahref="#hump.cameracamera:attach">camera:attach()</a></dt><dd>Attach camera.</dd><dt><ahref="#hump.cameracamera:detach">camera:detach()</a></dt><dd>Detach camera.</dd><dt><ahref="#hump.cameracamera:draw">camera:draw()</a></dt><dd>Attach, draw, then detach.</dd><dt><ahref="#hump.cameracamera:worldCoords">camera:worldCoords()</a></dt><dd>Convert point to world coordinates.</dd><dt><ahref="#hump.cameracamera:cameraCoords">camera:cameraCoords()</a></dt><dd>Convert point to camera coordinates.</dd><dt><ahref="#hump.cameracamera:mousepos">camera:mousepos()</a></dt><dd>Get mouse position in world coordinates.</dd></dl></div><divclass="ref-block"id="hump.cameranew"><h4>function <spanclass="name">new</span><spanclass="arglist">(x,y, zoom, rot)</span><aclass="top"href="#hump.camera">^top</a></h4><p>Creates a new camera. You can access the camera position using <codeclass="lua">camera.x,
camera.y</code>, the zoom using <codeclass="lua">camera.scale</code> and the rotation using <codeclass="lua">camera.rot</code>.</p>
</div></div><divclass="ref-block"id="hump.cameracamera:move"><h4>function <spanclass="name">camera:move</span><spanclass="arglist">(dx,dy)</span><aclass="top"href="#hump.camera">^top</a></h4><p>Move the camera <em>by</em> some vector. To set the position, use
</div></div><divclass="ref-block"id="hump.cameracamera:lookAt"><h4>function <spanclass="name">camera:lookAt</span><spanclass="arglist">(x,y)</span><aclass="top"href="#hump.camera">^top</a></h4><p>Let the camera look at a point. In other words, it sets the camera position. To
move the camera <em>by</em> some amount, use <ahref="#hump.cameramove"><codeclass="lua">camera:move(x,y)</code></a>.</p>
<p>This function is shortcut to <codeclass="lua">camera.x,camera.y = x, y</code>.</p>
</div></div><divclass="ref-block"id="hump.cameracamera:rotate"><h4>function <spanclass="name">camera:rotate</span><spanclass="arglist">(angle)</span><aclass="top"href="#hump.camera">^top</a></h4><p>Rotate the camera by some angle. To set the angle use <codeclass="lua">camera.rot = new_angle</code>.</p>
<p>This function is shortcut to <codeclass="lua">camera.rot = camera.rot + angle</code>.</p>
</div></div><divclass="ref-block"id="hump.cameracamera:attach"><h4>function <spanclass="name">camera:attach</span><spanclass="arglist">()</span><aclass="top"href="#hump.camera">^top</a></h4><p>Start looking through the camera.</p>
<p>Apply camera transformations, i.e. move, scale and rotate everything until
<codeclass="lua">camera:detach()</code> as if looking through the camera.</p>
</div></div><divclass="ref-block"id="hump.cameracamera:detach"><h4>function <spanclass="name">camera:detach</span><spanclass="arglist">()</span><aclass="top"href="#hump.camera">^top</a></h4><p>Stop looking through the camera.</p>
</div></div><divclass="ref-block"id="hump.cameracamera:draw"><h4>function <spanclass="name">camera:draw</span><spanclass="arglist">(func)</span><aclass="top"href="#hump.camera">^top</a></h4><p>Wrap a function between a <codeclass="lua">camera:attach()/camera:detach()</code> pair:</p>
</div></div><divclass="ref-block"id="hump.cameracamera:worldCoords"><h4>function <spanclass="name">camera:worldCoords</span><spanclass="arglist">(x, y)</span><aclass="top"href="#hump.camera">^top</a></h4><p>Because a camera has a point it looks at, a rotation and a zoom factor, it
defines a coordinate system. A point now has two sets of coordinates: One
defines where the point is to be found in the game world, and the other
describes the position on the computer screen. The first set of coordinates is
called <em>world coordinates</em>, the second one <em>camera coordinates</em>. Sometimes it
is needed to convert between the two coordinate systems, for example to get the
position of a mouse click in the game world in a strategy game, or to see if an
object is visible on the screen.</p>
<p><codeclass="lua">camera:worldCoords(x,y)</code> and <codeclass="lua">camera:cameraCoords(x,y)</code> transform a point
</div></div><divclass="ref-block"id="hump.cameracamera:cameraCoords"><h4>function <spanclass="name">camera:cameraCoords</span><spanclass="arglist">(x, y)</span><aclass="top"href="#hump.camera">^top</a></h4><p>Because a camera has a point it looks at, a rotation and a zoom factor, it
defines a coordinate system. A point now has two sets of coordinates: One
defines where the point is to be found in the game world, and the other
describes the position on the computer screen. The first set of coordinates is
called <em>world coordinates</em>, the second one <em>camera coordinates</em>. Sometimes it
is needed to convert between the two coordinate systems, for example to get the
position of a mouse click in the game world in a strategy game, or to see if an
object is visible on the screen.</p>
<p><codeclass="lua">camera:worldCoords(x,y)</code> and <codeclass="lua">camera:cameraCoords(x,y)</code> transform a point
</div></div><divclass="ref-block"id="hump.cameracamera:mousepos"><h4>function <spanclass="name">camera:mousepos</span><spanclass="arglist">()</span><aclass="top"href="#hump.camera">^top</a></h4><p>Shortcut to <codeclass="lua">camera:worldCoords(love.mouse.getPosition())</code>.</p>
</div></div><divclass="outer-block"id="Download"><h3>Download<aclass="top"href="#top">^top</a></h3><divclass="preamble"><p>You can view and download the individual modules on github: <ahref="http://github.com/vrld/hump">vrld/hump</a>
