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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
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<title>Open Dynamics Engine: World</title>
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<h1>World</h1><table border="0" cellpadding="0" cellspacing="0">
<tr><td></td></tr>
<tr><td colspan="2"><br><h2>Functions</h2></td></tr>
<tr><td class="memItemLeft" nowrap align="right" valign="top">ODE_API dWorldID </td><td class="memItemRight" valign="bottom"><a class="el" href="group__world.html#g929067266d630fb745f752042d685fc7">dWorldCreate</a> (void)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Create a new, empty world and return its ID number. <a href="#g929067266d630fb745f752042d685fc7"></a><br></td></tr>
<tr><td class="memItemLeft" nowrap align="right" valign="top">ODE_API void </td><td class="memItemRight" valign="bottom"><a class="el" href="group__world.html#g5a2e5b1d2d6a1376dca239b488e629f9">dWorldDestroy</a> (dWorldID world)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Destroy a world and everything in it. <a href="#g5a2e5b1d2d6a1376dca239b488e629f9"></a><br></td></tr>
<tr><td class="memItemLeft" nowrap align="right" valign="top">ODE_API void </td><td class="memItemRight" valign="bottom"><a class="el" href="group__world.html#ga1b220b922215b335572c699cf8f8cad">dWorldSetGravity</a> (dWorldID, dReal x, dReal y, dReal z)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Set the world's global gravity vector. <a href="#ga1b220b922215b335572c699cf8f8cad"></a><br></td></tr>
<tr><td class="memItemLeft" nowrap align="right" valign="top"><a class="anchor" name="ge1a29b6a91cc1910a982c916ae4dee4a"></a><!-- doxytag: member="world::dWorldGetGravity" ref="ge1a29b6a91cc1910a982c916ae4dee4a" args="(dWorldID, dVector3 gravity)" -->
ODE_API void </td><td class="memItemRight" valign="bottom"><a class="el" href="group__world.html#ge1a29b6a91cc1910a982c916ae4dee4a">dWorldGetGravity</a> (dWorldID, dVector3 gravity)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Get the gravity vector for a given world. <br></td></tr>
<tr><td class="memItemLeft" nowrap align="right" valign="top">ODE_API void </td><td class="memItemRight" valign="bottom"><a class="el" href="group__world.html#gacd0778bdaa939d22f093fc2d5d5f868">dWorldSetERP</a> (dWorldID, dReal erp)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Set the global ERP value, that controls how much error correction is performed in each time step. <a href="#gacd0778bdaa939d22f093fc2d5d5f868"></a><br></td></tr>
<tr><td class="memItemLeft" nowrap align="right" valign="top">ODE_API dReal </td><td class="memItemRight" valign="bottom"><a class="el" href="group__world.html#g033cd87a0b22889a94d4d84149bda5a0">dWorldGetERP</a> (dWorldID)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Get the error reduction parameter. <a href="#g033cd87a0b22889a94d4d84149bda5a0"></a><br></td></tr>
<tr><td class="memItemLeft" nowrap align="right" valign="top">ODE_API void </td><td class="memItemRight" valign="bottom"><a class="el" href="group__world.html#g8b7913fe46d0afc468418c655da79233">dWorldSetCFM</a> (dWorldID, dReal cfm)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Set the global CFM (constraint force mixing) value. <a href="#g8b7913fe46d0afc468418c655da79233"></a><br></td></tr>
<tr><td class="memItemLeft" nowrap align="right" valign="top">ODE_API dReal </td><td class="memItemRight" valign="bottom"><a class="el" href="group__world.html#gc7a431f2b3fc6f887fe91ad676828ba3">dWorldGetCFM</a> (dWorldID)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Get the constraint force mixing value. <a href="#gc7a431f2b3fc6f887fe91ad676828ba3"></a><br></td></tr>
<tr><td class="memItemLeft" nowrap align="right" valign="top">ODE_API void </td><td class="memItemRight" valign="bottom"><a class="el" href="group__world.html#g8f547ebeb3deed27e0f7b8143d475f50">dWorldStep</a> (dWorldID, dReal stepsize)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Step the world. <a href="#g8f547ebeb3deed27e0f7b8143d475f50"></a><br></td></tr>
<tr><td class="memItemLeft" nowrap align="right" valign="top">ODE_API void </td><td class="memItemRight" valign="bottom"><a class="el" href="group__world.html#ga9c564b4dd7d8fa4c6f4b32dd95fc33a">dWorldImpulseToForce</a> (dWorldID, dReal stepsize, dReal ix, dReal iy, dReal iz, dVector3 force)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Converts an impulse to a force. <a href="#ga9c564b4dd7d8fa4c6f4b32dd95fc33a"></a><br></td></tr>
<tr><td class="memItemLeft" nowrap align="right" valign="top">ODE_API void </td><td class="memItemRight" valign="bottom"><a class="el" href="group__world.html#gc24fadc1d42b65ca3563e40bc1f0fec1">dWorldQuickStep</a> (dWorldID w, dReal stepsize)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Step the world. <a href="#gc24fadc1d42b65ca3563e40bc1f0fec1"></a><br></td></tr>
<tr><td class="memItemLeft" nowrap align="right" valign="top">ODE_API void </td><td class="memItemRight" valign="bottom"><a class="el" href="group__world.html#g9d852689d87d28a3d4947eda59c5ba7e">dWorldSetQuickStepNumIterations</a> (dWorldID, int num)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Set the number of iterations that the QuickStep method performs per step. <a href="#g9d852689d87d28a3d4947eda59c5ba7e"></a><br></td></tr>
<tr><td class="memItemLeft" nowrap align="right" valign="top">ODE_API int </td><td class="memItemRight" valign="bottom"><a class="el" href="group__world.html#ga51acfac06347fd27ff926d37672ce3c">dWorldGetQuickStepNumIterations</a> (dWorldID)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Get the number of iterations that the QuickStep method performs per step. <a href="#ga51acfac06347fd27ff926d37672ce3c"></a><br></td></tr>
<tr><td class="memItemLeft" nowrap align="right" valign="top">ODE_API void </td><td class="memItemRight" valign="bottom"><a class="el" href="group__world.html#gf741ee61e3f9981ae102729f23aad535">dWorldSetQuickStepW</a> (dWorldID, dReal over_relaxation)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Set the SOR over-relaxation parameter. <a href="#gf741ee61e3f9981ae102729f23aad535"></a><br></td></tr>
<tr><td class="memItemLeft" nowrap align="right" valign="top">ODE_API dReal </td><td class="memItemRight" valign="bottom"><a class="el" href="group__world.html#ga7fef06f7a8293f21778939dfea36951">dWorldGetQuickStepW</a> (dWorldID)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Get the SOR over-relaxation parameter. <a href="#ga7fef06f7a8293f21778939dfea36951"></a><br></td></tr>
<tr><td class="memItemLeft" nowrap align="right" valign="top">ODE_API void </td><td class="memItemRight" valign="bottom"><a class="el" href="group__world.html#g2cec4be3f40d49c5950ceac1a28440d8">dWorldSetContactMaxCorrectingVel</a> (dWorldID, dReal vel)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Set the maximum correcting velocity that contacts are allowed to generate. <a href="#g2cec4be3f40d49c5950ceac1a28440d8"></a><br></td></tr>
<tr><td class="memItemLeft" nowrap align="right" valign="top"><a class="anchor" name="g7673e6d0db3ddb319642caea7d14959d"></a><!-- doxytag: member="world::dWorldGetContactMaxCorrectingVel" ref="g7673e6d0db3ddb319642caea7d14959d" args="(dWorldID)" -->
ODE_API dReal </td><td class="memItemRight" valign="bottom"><a class="el" href="group__world.html#g7673e6d0db3ddb319642caea7d14959d">dWorldGetContactMaxCorrectingVel</a> (dWorldID)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Get the maximum correcting velocity that contacts are allowed to generated. <br></td></tr>
<tr><td class="memItemLeft" nowrap align="right" valign="top">ODE_API void </td><td class="memItemRight" valign="bottom"><a class="el" href="group__world.html#g8f6f964bc15b6cf0937d3214f6e3a1f1">dWorldSetContactSurfaceLayer</a> (dWorldID, dReal depth)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Set the depth of the surface layer around all geometry objects. <a href="#g8f6f964bc15b6cf0937d3214f6e3a1f1"></a><br></td></tr>
<tr><td class="memItemLeft" nowrap align="right" valign="top">ODE_API dReal </td><td class="memItemRight" valign="bottom"><a class="el" href="group__world.html#g97e1c98f55d9b56d00e7838900ad5e58">dWorldGetContactSurfaceLayer</a> (dWorldID)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Get the depth of the surface layer around all geometry objects. <a href="#g97e1c98f55d9b56d00e7838900ad5e58"></a><br></td></tr>
<tr><td class="memItemLeft" nowrap align="right" valign="top">ODE_API void </td><td class="memItemRight" valign="bottom"><a class="el" href="group__world.html#gefa68c714bb3c8f70503f101ea062c03">dWorldStepFast1</a> (dWorldID, dReal stepsize, int maxiterations)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Step the world using the StepFast1 algorithm. <a href="#gefa68c714bb3c8f70503f101ea062c03"></a><br></td></tr>
</table>
<hr><a name="_details"></a><h2>Detailed Description</h2>
The world object is a container for rigid bodies and joints. Objects in different worlds can not interact, for example rigid bodies from two different worlds can not collide.<p>
All the objects in a world exist at the same point in time, thus one reason to use separate worlds is to simulate systems at different rates. Most applications will only need one world. <hr><h2>Function Documentation</h2>
<a class="anchor" name="g929067266d630fb745f752042d685fc7"></a><!-- doxytag: member="objects.h::dWorldCreate" ref="g929067266d630fb745f752042d685fc7" args="(void)" -->
<div class="memitem">
<div class="memproto">
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<td class="memname">ODE_API dWorldID dWorldCreate </td>
<td>(</td>
<td class="paramtype">void </td>
<td class="paramname"> </td>
<td> ) </td>
<td width="100%"></td>
</tr>
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<div class="memdoc">
<p>
Create a new, empty world and return its ID number.
<p>
<dl class="return" compact><dt><b>Returns:</b></dt><dd>an identifier </dd></dl>
</div>
</div><p>
<a class="anchor" name="g5a2e5b1d2d6a1376dca239b488e629f9"></a><!-- doxytag: member="objects.h::dWorldDestroy" ref="g5a2e5b1d2d6a1376dca239b488e629f9" args="(dWorldID world)" -->
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<td class="memname">ODE_API void dWorldDestroy </td>
<td>(</td>
<td class="paramtype">dWorldID </td>
<td class="paramname"> <em>world</em> </td>
<td> ) </td>
<td width="100%"></td>
</tr>
</table>
</div>
<div class="memdoc">
<p>
Destroy a world and everything in it.
<p>
This includes all bodies, and all joints that are not part of a joint group. Joints that are part of a joint group will be deactivated, and can be destroyed by calling, for example, <a class="el" href="group__joints.html#g6e055bac8a0a3261bda3b6d07499c4ea" title="Empty a joint group.">dJointGroupEmpty()</a>.<p>
<dl compact><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>world</em> </td><td>the identifier for the world the be destroyed. </td></tr>
</table>
</dl>
</div>
</div><p>
<a class="anchor" name="gc7a431f2b3fc6f887fe91ad676828ba3"></a><!-- doxytag: member="objects.h::dWorldGetCFM" ref="gc7a431f2b3fc6f887fe91ad676828ba3" args="(dWorldID)" -->
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<td class="memname">ODE_API dReal dWorldGetCFM </td>
<td>(</td>
<td class="paramtype">dWorldID </td>
<td class="paramname"> </td>
<td> ) </td>
<td width="100%"></td>
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<div class="memdoc">
<p>
Get the constraint force mixing value.
<p>
<dl class="return" compact><dt><b>Returns:</b></dt><dd>CFM value </dd></dl>
</div>
</div><p>
<a class="anchor" name="g97e1c98f55d9b56d00e7838900ad5e58"></a><!-- doxytag: member="objects.h::dWorldGetContactSurfaceLayer" ref="g97e1c98f55d9b56d00e7838900ad5e58" args="(dWorldID)" -->
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<td class="memname">ODE_API dReal dWorldGetContactSurfaceLayer </td>
<td>(</td>
<td class="paramtype">dWorldID </td>
<td class="paramname"> </td>
<td> ) </td>
<td width="100%"></td>
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<div class="memdoc">
<p>
Get the depth of the surface layer around all geometry objects.
<p>
<dl class="return" compact><dt><b>Returns:</b></dt><dd>the depth </dd></dl>
</div>
</div><p>
<a class="anchor" name="g033cd87a0b22889a94d4d84149bda5a0"></a><!-- doxytag: member="objects.h::dWorldGetERP" ref="g033cd87a0b22889a94d4d84149bda5a0" args="(dWorldID)" -->
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<td class="memname">ODE_API dReal dWorldGetERP </td>
<td>(</td>
<td class="paramtype">dWorldID </td>
<td class="paramname"> </td>
<td> ) </td>
<td width="100%"></td>
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<div class="memdoc">
<p>
Get the error reduction parameter.
<p>
<dl class="return" compact><dt><b>Returns:</b></dt><dd>ERP value </dd></dl>
</div>
</div><p>
<a class="anchor" name="ga51acfac06347fd27ff926d37672ce3c"></a><!-- doxytag: member="objects.h::dWorldGetQuickStepNumIterations" ref="ga51acfac06347fd27ff926d37672ce3c" args="(dWorldID)" -->
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<td class="memname">ODE_API int dWorldGetQuickStepNumIterations </td>
<td>(</td>
<td class="paramtype">dWorldID </td>
<td class="paramname"> </td>
<td> ) </td>
<td width="100%"></td>
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<div class="memdoc">
<p>
Get the number of iterations that the QuickStep method performs per step.
<p>
<dl class="return" compact><dt><b>Returns:</b></dt><dd>nr of iterations </dd></dl>
</div>
</div><p>
<a class="anchor" name="ga7fef06f7a8293f21778939dfea36951"></a><!-- doxytag: member="objects.h::dWorldGetQuickStepW" ref="ga7fef06f7a8293f21778939dfea36951" args="(dWorldID)" -->
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<td class="memname">ODE_API dReal dWorldGetQuickStepW </td>
<td>(</td>
<td class="paramtype">dWorldID </td>
<td class="paramname"> </td>
<td> ) </td>
<td width="100%"></td>
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<p>
Get the SOR over-relaxation parameter.
<p>
<dl class="return" compact><dt><b>Returns:</b></dt><dd>the over-relaxation setting </dd></dl>
</div>
</div><p>
<a class="anchor" name="ga9c564b4dd7d8fa4c6f4b32dd95fc33a"></a><!-- doxytag: member="objects.h::dWorldImpulseToForce" ref="ga9c564b4dd7d8fa4c6f4b32dd95fc33a" args="(dWorldID, dReal stepsize, dReal ix, dReal iy, dReal iz, dVector3 force)" -->
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<td class="memname">ODE_API void dWorldImpulseToForce </td>
<td>(</td>
<td class="paramtype">dWorldID </td>
<td class="paramname">, </td>
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<td class="paramkey"></td>
<td></td>
<td class="paramtype">dReal </td>
<td class="paramname"> <em>stepsize</em>, </td>
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<td class="paramkey"></td>
<td></td>
<td class="paramtype">dReal </td>
<td class="paramname"> <em>ix</em>, </td>
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<td class="paramkey"></td>
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<td class="paramtype">dReal </td>
<td class="paramname"> <em>iy</em>, </td>
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<td class="paramkey"></td>
<td></td>
<td class="paramtype">dReal </td>
<td class="paramname"> <em>iz</em>, </td>
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<td class="paramkey"></td>
<td></td>
<td class="paramtype">dVector3 </td>
<td class="paramname"> <em>force</em></td><td> </td>
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Converts an impulse to a force.
<p>
<dl class="remark" compact><dt><b>Remarks:</b></dt><dd>If you want to apply a linear or angular impulse to a rigid body, instead of a force or a torque, then you can use this function to convert the desired impulse into a force/torque vector before calling the BodyAdd... function. The current algorithm simply scales the impulse by 1/stepsize, where stepsize is the step size for the next step that will be taken. This function is given a dWorldID because, in the future, the force computation may depend on integrator parameters that are set as properties of the world. </dd></dl>
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<a class="anchor" name="gc24fadc1d42b65ca3563e40bc1f0fec1"></a><!-- doxytag: member="objects.h::dWorldQuickStep" ref="gc24fadc1d42b65ca3563e40bc1f0fec1" args="(dWorldID w, dReal stepsize)" -->
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<td class="memname">ODE_API void dWorldQuickStep </td>
<td>(</td>
<td class="paramtype">dWorldID </td>
<td class="paramname"> <em>w</em>, </td>
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<td class="paramtype">dReal </td>
<td class="paramname"> <em>stepsize</em></td><td> </td>
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<p>
Step the world.
<p>
<dl class="remark" compact><dt><b>Remarks:</b></dt><dd>This uses an iterative method that takes time on the order of m*N and memory on the order of m, where m is the total number of constraint rows N is the number of iterations. For large systems this is a lot faster than <a class="el" href="group__world.html#g8f547ebeb3deed27e0f7b8143d475f50" title="Step the world.">dWorldStep()</a>, but it is less accurate. <p>
QuickStep is great for stacks of objects especially when the auto-disable feature is used as well. However, it has poor accuracy for near-singular systems. Near-singular systems can occur when using high-friction contacts, motors, or certain articulated structures. For example, a robot with multiple legs sitting on the ground may be near-singular. <p>
There are ways to help overcome QuickStep's inaccuracy problems: <ul>
<li>Increase CFM. </li>
<li>Reduce the number of contacts in your system (e.g. use the minimum number of contacts for the feet of a robot or creature). </li>
<li>Don't use excessive friction in the contacts. </li>
<li>Use contact slip if appropriate </li>
<li>Avoid kinematic loops (however, kinematic loops are inevitable in legged creatures). </li>
<li>Don't use excessive motor strength. force-based motors instead of velocity-based motors.</li>
</ul>
Increasing the number of QuickStep iterations may help a little bit, but it is not going to help much if your system is really near singular. </dd></dl>
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<a class="anchor" name="g8b7913fe46d0afc468418c655da79233"></a><!-- doxytag: member="objects.h::dWorldSetCFM" ref="g8b7913fe46d0afc468418c655da79233" args="(dWorldID, dReal cfm)" -->
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<td class="memname">ODE_API void dWorldSetCFM </td>
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<td class="paramtype">dWorldID </td>
<td class="paramname">, </td>
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<td class="paramkey"></td>
<td></td>
<td class="paramtype">dReal </td>
<td class="paramname"> <em>cfm</em></td><td> </td>
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<p>
Set the global CFM (constraint force mixing) value.
<p>
<dl compact><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>cfm</em> </td><td>Typical values are in the range {10^{-9}} -- 1. The default is 10^-5 if single precision is being used, or 10^-10 if double precision is being used. </td></tr>
</table>
</dl>
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<a class="anchor" name="g2cec4be3f40d49c5950ceac1a28440d8"></a><!-- doxytag: member="objects.h::dWorldSetContactMaxCorrectingVel" ref="g2cec4be3f40d49c5950ceac1a28440d8" args="(dWorldID, dReal vel)" -->
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<td class="memname">ODE_API void dWorldSetContactMaxCorrectingVel </td>
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<td class="paramtype">dWorldID </td>
<td class="paramname">, </td>
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<td class="paramname"> <em>vel</em></td><td> </td>
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<p>
Set the maximum correcting velocity that contacts are allowed to generate.
<p>
<dl compact><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>vel</em> </td><td>The default value is infinity (i.e. no limit). </td></tr>
</table>
</dl>
<dl class="remark" compact><dt><b>Remarks:</b></dt><dd>Reducing this value can help prevent "popping" of deeply embedded objects. </dd></dl>
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<a class="anchor" name="g8f6f964bc15b6cf0937d3214f6e3a1f1"></a><!-- doxytag: member="objects.h::dWorldSetContactSurfaceLayer" ref="g8f6f964bc15b6cf0937d3214f6e3a1f1" args="(dWorldID, dReal depth)" -->
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<td class="memname">ODE_API void dWorldSetContactSurfaceLayer </td>
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<td class="paramtype">dWorldID </td>
<td class="paramname">, </td>
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<td class="paramtype">dReal </td>
<td class="paramname"> <em>depth</em></td><td> </td>
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<p>
Set the depth of the surface layer around all geometry objects.
<p>
<dl class="remark" compact><dt><b>Remarks:</b></dt><dd>Contacts are allowed to sink into the surface layer up to the given depth before coming to rest. </dd></dl>
<dl compact><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>depth</em> </td><td>The default value is zero. </td></tr>
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<dl class="remark" compact><dt><b>Remarks:</b></dt><dd>Increasing this to some small value (e.g. 0.001) can help prevent jittering problems due to contacts being repeatedly made and broken. </dd></dl>
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<a class="anchor" name="gacd0778bdaa939d22f093fc2d5d5f868"></a><!-- doxytag: member="objects.h::dWorldSetERP" ref="gacd0778bdaa939d22f093fc2d5d5f868" args="(dWorldID, dReal erp)" -->
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<td class="memname">ODE_API void dWorldSetERP </td>
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<td class="paramtype">dWorldID </td>
<td class="paramname">, </td>
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<td class="paramname"> <em>erp</em></td><td> </td>
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<p>
Set the global ERP value, that controls how much error correction is performed in each time step.
<p>
<dl compact><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>dWorldID</em> </td><td>the identifier of the world. </td></tr>
<tr><td valign="top"></td><td valign="top"><em>erp</em> </td><td>Typical values are in the range 0.1--0.8. The default is 0.2. </td></tr>
</table>
</dl>
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<a class="anchor" name="ga1b220b922215b335572c699cf8f8cad"></a><!-- doxytag: member="objects.h::dWorldSetGravity" ref="ga1b220b922215b335572c699cf8f8cad" args="(dWorldID, dReal x, dReal y, dReal z)" -->
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<td class="memname">ODE_API void dWorldSetGravity </td>
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<td class="paramname"> <em>x</em>, </td>
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<td class="paramname"> <em>y</em>, </td>
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<td class="paramtype">dReal </td>
<td class="paramname"> <em>z</em></td><td> </td>
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<p>
Set the world's global gravity vector.
<p>
The units are m/s^2, so Earth's gravity vector would be (0,0,-9.81), assuming that +z is up. The default is no gravity, i.e. (0,0,0).
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<a class="anchor" name="g9d852689d87d28a3d4947eda59c5ba7e"></a><!-- doxytag: member="objects.h::dWorldSetQuickStepNumIterations" ref="g9d852689d87d28a3d4947eda59c5ba7e" args="(dWorldID, int num)" -->
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<td class="memname">ODE_API void dWorldSetQuickStepNumIterations </td>
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<p>
Set the number of iterations that the QuickStep method performs per step.
<p>
<dl class="remark" compact><dt><b>Remarks:</b></dt><dd>More iterations will give a more accurate solution, but will take longer to compute. </dd></dl>
<dl compact><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>num</em> </td><td>The default is 20 iterations. </td></tr>
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<a class="anchor" name="gf741ee61e3f9981ae102729f23aad535"></a><!-- doxytag: member="objects.h::dWorldSetQuickStepW" ref="gf741ee61e3f9981ae102729f23aad535" args="(dWorldID, dReal over_relaxation)" -->
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<td class="memname">ODE_API void dWorldSetQuickStepW </td>
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<td class="paramtype">dWorldID </td>
<td class="paramname">, </td>
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<td class="paramtype">dReal </td>
<td class="paramname"> <em>over_relaxation</em></td><td> </td>
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<p>
Set the SOR over-relaxation parameter.
<p>
<dl compact><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>over_relaxation</em> </td><td>value to use by SOR </td></tr>
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<a class="anchor" name="g8f547ebeb3deed27e0f7b8143d475f50"></a><!-- doxytag: member="objects.h::dWorldStep" ref="g8f547ebeb3deed27e0f7b8143d475f50" args="(dWorldID, dReal stepsize)" -->
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<td class="memname">ODE_API void dWorldStep </td>
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<td class="paramtype">dWorldID </td>
<td class="paramname">, </td>
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<td class="paramkey"></td>
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<td class="paramtype">dReal </td>
<td class="paramname"> <em>stepsize</em></td><td> </td>
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<p>
Step the world.
<p>
This uses a "big matrix" method that takes time on the order of m^3 and memory on the order of m^2, where m is the total number of constraint rows. For large systems this will use a lot of memory and can be very slow, but this is currently the most accurate method.<p>
<dl compact><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>stepsize</em> </td><td>The number of seconds that the simulation has to advance. </td></tr>
</table>
</dl>
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<a class="anchor" name="gefa68c714bb3c8f70503f101ea062c03"></a><!-- doxytag: member="objects.h::dWorldStepFast1" ref="gefa68c714bb3c8f70503f101ea062c03" args="(dWorldID, dReal stepsize, int maxiterations)" -->
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<td class="paramtype">dWorldID </td>
<td class="paramname">, </td>
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<td class="paramname"> <em>stepsize</em>, </td>
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<td class="paramname"> <em>maxiterations</em></td><td> </td>
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<p>
Step the world using the StepFast1 algorithm.
<p>
<dl compact><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>stepsize</em> </td><td>the nr of seconds to advance the simulation. </td></tr>
<tr><td valign="top"></td><td valign="top"><em>maxiterations</em> </td><td>The number of iterations to perform. </td></tr>
</table>
</dl>
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</div><p>
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