Modified source engine (2017) developed by valve and leaked in 2020. Not for commercial purporses
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//========= Copyright Valve Corporation, All rights reserved. ============//
//
// Purpose: Utility functions for using debug overlays to visualize information
// in the world. Uses the IVDebugOverlay interface.
//
//=============================================================================//
#include "cbase.h"
#include "debugoverlay_shared.h"
#include "mathlib/mathlib.h"
// memdbgon must be the last include file in a .cpp file!!!
#include "tier0/memdbgon.h"
#define MAX_OVERLAY_DIST_SQR 90000000
//-----------------------------------------------------------------------------
// Purpose: Local player on the server or client
//-----------------------------------------------------------------------------
CBasePlayer *GetLocalPlayer( void )
{
#if defined( CLIENT_DLL)
return C_BasePlayer::GetLocalPlayer();
#else
return UTIL_GetListenServerHost();
#endif
}
//-----------------------------------------------------------------------------
// Purpose: Debug player by index
//-----------------------------------------------------------------------------
CBasePlayer *GetDebugPlayer( void )
{
#if defined( CLIENT_DLL )
//NOTENOTE: This doesn't necessarily make sense on the client
return GetLocalPlayer();
#else
return UTIL_PlayerByIndex(CBaseEntity::m_nDebugPlayer);
#endif
}
//-----------------------------------------------------------------------------
// Purpose: Draw a box with no orientation
//-----------------------------------------------------------------------------
void NDebugOverlay::Box(const Vector &origin, const Vector &mins, const Vector &maxs, int r, int g, int b, int a, float flDuration)
{
BoxAngles( origin, mins, maxs, vec3_angle, r, g, b, a, flDuration );
}
//-----------------------------------------------------------------------------
// Purpose: Draw box oriented to a Vector direction
//-----------------------------------------------------------------------------
void NDebugOverlay::BoxDirection(const Vector &origin, const Vector &mins, const Vector &maxs, const Vector &orientation, int r, int g, int b, int a, float duration)
{
// convert forward vector to angles
QAngle f_angles = vec3_angle;
f_angles.y = UTIL_VecToYaw( orientation );
BoxAngles( origin, mins, maxs, f_angles, r, g, b, a, duration );
}
//-----------------------------------------------------------------------------
// Purpose: Draw box oriented to a QAngle direction
//-----------------------------------------------------------------------------
void NDebugOverlay::BoxAngles(const Vector &origin, const Vector &mins, const Vector &maxs, const QAngle &angles, int r, int g, int b, int a, float duration)
{
if ( debugoverlay )
{
debugoverlay->AddBoxOverlay( origin, mins, maxs, angles, r, g, b, a, duration );
}
}
//-----------------------------------------------------------------------------
// Purpose: Draws a swept box
//-----------------------------------------------------------------------------
void NDebugOverlay::SweptBox( const Vector& start, const Vector& end, const Vector& mins, const Vector& maxs, const QAngle & angles, int r, int g, int b, int a, float flDuration)
{
if ( debugoverlay )
{
debugoverlay->AddSweptBoxOverlay( start, end, mins, maxs, angles, r, g, b, a, flDuration );
}
}
//-----------------------------------------------------------------------------
// Purpose: Draws a box around an entity
//-----------------------------------------------------------------------------
void NDebugOverlay::EntityBounds( const CBaseEntity *pEntity, int r, int g, int b, int a, float flDuration )
{
const CCollisionProperty *pCollide = pEntity->CollisionProp();
BoxAngles( pCollide->GetCollisionOrigin(), pCollide->OBBMins(), pCollide->OBBMaxs(), pCollide->GetCollisionAngles(), r, g, b, a, flDuration );
}
//-----------------------------------------------------------------------------
// Purpose: Draws a line from one position to another
//-----------------------------------------------------------------------------
void NDebugOverlay::Line( const Vector &origin, const Vector &target, int r, int g, int b, bool noDepthTest, float duration )
{
// --------------------------------------------------------------
// Clip the line before sending so we
// don't overflow the client message buffer
// --------------------------------------------------------------
CBasePlayer *player = GetLocalPlayer();
if ( player == NULL )
return;
// Clip line that is far away
if (((player->GetAbsOrigin() - origin).LengthSqr() > MAX_OVERLAY_DIST_SQR) &&
((player->GetAbsOrigin() - target).LengthSqr() > MAX_OVERLAY_DIST_SQR) )
return;
// Clip line that is behind the client
Vector clientForward;
player->EyeVectors( &clientForward );
Vector toOrigin = origin - player->GetAbsOrigin();
Vector toTarget = target - player->GetAbsOrigin();
float dotOrigin = DotProduct(clientForward,toOrigin);
float dotTarget = DotProduct(clientForward,toTarget);
if (dotOrigin < 0 && dotTarget < 0)
return;
if ( debugoverlay )
{
debugoverlay->AddLineOverlay( origin, target, r, g, b, noDepthTest, duration );
}
}
//-----------------------------------------------------------------------------
// Purpose: Draw triangle
//-----------------------------------------------------------------------------
void NDebugOverlay::Triangle( const Vector &p1, const Vector &p2, const Vector &p3, int r, int g, int b, int a, bool noDepthTest, float duration )
{
CBasePlayer *player = GetLocalPlayer();
if ( !player )
return;
// Clip triangles that are far away
Vector to1 = p1 - player->GetAbsOrigin();
Vector to2 = p2 - player->GetAbsOrigin();
Vector to3 = p3 - player->GetAbsOrigin();
if ((to1.LengthSqr() > MAX_OVERLAY_DIST_SQR) &&
(to2.LengthSqr() > MAX_OVERLAY_DIST_SQR) &&
(to3.LengthSqr() > MAX_OVERLAY_DIST_SQR))
{
return;
}
// Clip triangles that are behind the client
Vector clientForward;
player->EyeVectors( &clientForward );
float dot1 = DotProduct(clientForward, to1);
float dot2 = DotProduct(clientForward, to2);
float dot3 = DotProduct(clientForward, to3);
if (dot1 < 0 && dot2 < 0 && dot3 < 0)
return;
if ( debugoverlay )
{
debugoverlay->AddTriangleOverlay( p1, p2, p3, r, g, b, a, noDepthTest, duration );
}
}
//-----------------------------------------------------------------------------
// Purpose: Draw entity text overlay
//-----------------------------------------------------------------------------
void NDebugOverlay::EntityText( int entityID, int text_offset, const char *text, float duration, int r, int g, int b, int a )
{
if ( debugoverlay )
{
debugoverlay->AddEntityTextOverlay( entityID, text_offset, duration,
(int)clamp(r * 255.f,0.f,255.f), (int)clamp(g * 255.f,0.f,255.f), (int)clamp(b * 255.f,0.f,255.f),
(int)clamp(a * 255.f,0.f,255.f), text );
}
}
//-----------------------------------------------------------------------------
// Purpose: Draw entity text overlay at a specific position
//-----------------------------------------------------------------------------
void NDebugOverlay::EntityTextAtPosition( const Vector &origin, int text_offset, const char *text, float duration, int r, int g, int b, int a )
{
if ( debugoverlay )
{
debugoverlay->AddTextOverlayRGB( origin, text_offset, duration, r, g, b, a, "%s", text );
}
}
//-----------------------------------------------------------------------------
// Purpose: Add grid overlay
//-----------------------------------------------------------------------------
void NDebugOverlay::Grid( const Vector &vPosition )
{
if ( debugoverlay )
{
debugoverlay->AddGridOverlay( vPosition );
}
}
//-----------------------------------------------------------------------------
// Purpose: Draw debug text at a position
//-----------------------------------------------------------------------------
void NDebugOverlay::Text( const Vector &origin, const char *text, bool bViewCheck, float duration )
{
CBasePlayer *player = GetLocalPlayer();
if ( !player )
return;
// Clip text that is far away
if ( ( player->GetAbsOrigin() - origin ).LengthSqr() > MAX_OVERLAY_DIST_SQR )
return;
// Clip text that is behind the client
Vector clientForward;
player->EyeVectors( &clientForward );
Vector toText = origin - player->GetAbsOrigin();
float dotPr = DotProduct(clientForward,toText);
if (dotPr < 0)
return;
// Clip text that is obscured
if (bViewCheck)
{
trace_t tr;
UTIL_TraceLine(player->GetAbsOrigin(), origin, MASK_OPAQUE, NULL, COLLISION_GROUP_NONE, &tr);
if ((tr.endpos - origin).Length() > 10)
return;
}
if ( debugoverlay )
{
debugoverlay->AddTextOverlay( origin, duration, "%s", text );
}
}
//-----------------------------------------------------------------------------
// Purpose: Add debug overlay text with screen position
//-----------------------------------------------------------------------------
void NDebugOverlay::ScreenText( float flXpos, float flYpos, const char *text, int r, int g, int b, int a, float duration )
{
if ( debugoverlay )
{
debugoverlay->AddScreenTextOverlay( flXpos, flYpos, duration, r, g, b, a, text );
}
}
//-----------------------------------------------------------------------------
// Purpose: Draw a colored 3D cross of the given hull size at the given position
//-----------------------------------------------------------------------------
void NDebugOverlay::Cross3D(const Vector &position, const Vector &mins, const Vector &maxs, int r, int g, int b, bool noDepthTest, float fDuration )
{
Vector start = mins + position;
Vector end = maxs + position;
Line(start,end, r, g, b, noDepthTest,fDuration);
start.x += (maxs.x - mins.x);
end.x -= (maxs.x - mins.x);
Line(start,end, r, g, b, noDepthTest,fDuration);
start.y += (maxs.y - mins.y);
end.y -= (maxs.y - mins.y);
Line(start,end, r, g, b, noDepthTest,fDuration);
start.x -= (maxs.x - mins.x);
end.x += (maxs.x - mins.x);
Line(start,end, r, g, b, noDepthTest,fDuration);
}
//-----------------------------------------------------------------------------
// Purpose: Draw a colored 3D cross of the given size at the given position
//-----------------------------------------------------------------------------
void NDebugOverlay::Cross3D(const Vector &position, float size, int r, int g, int b, bool noDepthTest, float flDuration )
{
Line( position + Vector(size,0,0), position - Vector(size,0,0), r, g, b, noDepthTest, flDuration );
Line( position + Vector(0,size,0), position - Vector(0,size,0), r, g, b, noDepthTest, flDuration );
Line( position + Vector(0,0,size), position - Vector(0,0,size), r, g, b, noDepthTest, flDuration );
}
//-----------------------------------------------------------------------------
// Purpose: Draw an oriented, colored 3D cross of the given size at the given position (via a vector)
//-----------------------------------------------------------------------------
void NDebugOverlay::Cross3DOriented( const Vector &position, const QAngle &angles, float size, int r, int g, int b, bool noDepthTest, float flDuration )
{
Vector forward, right, up;
AngleVectors( angles, &forward, &right, &up );
forward *= size;
right *= size;
up *= size;
Line( position + right, position - right, r, g, b, noDepthTest, flDuration );
Line( position + forward, position - forward, r, g, b, noDepthTest, flDuration );
Line( position + up, position - up, r, g, b, noDepthTest, flDuration );
}
//-----------------------------------------------------------------------------
// Purpose: Draw an oriented, colored 3D cross of the given size at the given position (via a matrix)
//-----------------------------------------------------------------------------
void NDebugOverlay::Cross3DOriented( const matrix3x4_t &m, float size, int c, bool noDepthTest, float flDuration )
{
Vector forward, left, up, position;
MatrixGetColumn( m, 0, forward );
MatrixGetColumn( m, 1, left );
MatrixGetColumn( m, 2, up );
MatrixGetColumn( m, 3, position );
forward *= size;
left *= size;
up *= size;
Line( position + left, position - left, 0, c, 0, noDepthTest, flDuration );
Line( position + forward, position - forward, c, 0, 0, noDepthTest, flDuration );
Line( position + up, position - up, 0, 0, c, noDepthTest, flDuration );
}
//--------------------------------------------------------------------------------
// Purpose : Draw tick marks between start and end position of the given distance
// with text every tickTextDist steps apart.
//--------------------------------------------------------------------------------
void NDebugOverlay::DrawTickMarkedLine(const Vector &startPos, const Vector &endPos, float tickDist, int tickTextDist, int r, int g, int b, bool noDepthTest, float duration )
{
CBasePlayer* pPlayer = GetDebugPlayer();
if ( !pPlayer )
return;
Vector lineDir = (endPos - startPos);
float lineDist = VectorNormalize( lineDir );
int numTicks = lineDist/tickDist;
Vector vBodyDir;
#if defined( CLIENT_DLL )
AngleVectors( pPlayer->LocalEyeAngles(), &vBodyDir );
#else
vBodyDir = pPlayer->BodyDirection2D( );
#endif
Vector upVec = 4*vBodyDir;
Vector sideDir;
Vector tickPos = startPos;
int tickTextCnt = 0;
CrossProduct(lineDir, upVec, sideDir);
// First draw the line
Line(startPos, endPos, r,g,b,noDepthTest,duration);
// Now draw the ticks
for (int i=0;i<numTicks+1;i++)
{
// Draw tick mark
Vector tickLeft = tickPos - sideDir;
Vector tickRight = tickPos + sideDir;
// Draw tick mark text
if (tickTextCnt == tickTextDist)
{
char text[25];
Q_snprintf(text,sizeof(text),"%i",i);
Vector textPos = tickLeft + Vector(0,0,8);
Line(tickLeft, tickRight, 255,255,255,noDepthTest,duration);
Text( textPos, text, true, 0 );
tickTextCnt = 0;
}
else
{
Line(tickLeft, tickRight, r,g,b,noDepthTest,duration);
}
tickTextCnt++;
tickPos = tickPos + (tickDist * lineDir);
}
}
//------------------------------------------------------------------------------
// Purpose : Draw crosshair on ground where player is looking
//------------------------------------------------------------------------------
void NDebugOverlay::DrawGroundCrossHairOverlay( void )
{
CBasePlayer* pPlayer = GetDebugPlayer();
if ( !pPlayer )
return;
// Trace a line to where player is looking
Vector vForward;
Vector vSource = pPlayer->EyePosition();
pPlayer->EyeVectors( &vForward );
trace_t tr;
UTIL_TraceLine ( vSource, vSource + vForward * 2048, MASK_SOLID, pPlayer, COLLISION_GROUP_NONE, &tr);
float dotPr = DotProduct(Vector(0,0,1),tr.plane.normal);
if (tr.fraction != 1.0 && dotPr > 0.5)
{
tr.endpos.z += 1;
float scale = 6;
Vector startPos = tr.endpos + Vector (-scale,0,0);
Vector endPos = tr.endpos + Vector ( scale,0,0);
Line(startPos, endPos, 255, 0, 0,false,0);
startPos = tr.endpos + Vector (0,-scale,0);
endPos = tr.endpos + Vector (0, scale,0);
Line(startPos, endPos, 255, 0, 0,false,0);
}
}
//--------------------------------------------------------------------------------
// Purpose : Draw a horizontal arrow pointing in the specified direction
//--------------------------------------------------------------------------------
void NDebugOverlay::HorzArrow( const Vector &startPos, const Vector &endPos, float width, int r, int g, int b, int a, bool noDepthTest, float flDuration)
{
Vector lineDir = (endPos - startPos);
VectorNormalize( lineDir );
Vector upVec = Vector( 0, 0, 1 );
Vector sideDir;
float radius = width / 2.0;
CrossProduct(lineDir, upVec, sideDir);
Vector p1 = startPos - sideDir * radius;
Vector p2 = endPos - lineDir * width - sideDir * radius;
Vector p3 = endPos - lineDir * width - sideDir * width;
Vector p4 = endPos;
Vector p5 = endPos - lineDir * width + sideDir * width;
Vector p6 = endPos - lineDir * width + sideDir * radius;
Vector p7 = startPos + sideDir * radius;
// Outline the arrow
Line(p1, p2, r,g,b,noDepthTest,flDuration);
Line(p2, p3, r,g,b,noDepthTest,flDuration);
Line(p3, p4, r,g,b,noDepthTest,flDuration);
Line(p4, p5, r,g,b,noDepthTest,flDuration);
Line(p5, p6, r,g,b,noDepthTest,flDuration);
Line(p6, p7, r,g,b,noDepthTest,flDuration);
if ( a > 0 )
{
// Fill us in with triangles
Triangle( p5, p4, p3, r, g, b, a, noDepthTest, flDuration ); // Tip
Triangle( p1, p7, p6, r, g, b, a, noDepthTest, flDuration ); // Shaft
Triangle( p6, p2, p1, r, g, b, a, noDepthTest, flDuration );
// And backfaces
Triangle( p3, p4, p5, r, g, b, a, noDepthTest, flDuration ); // Tip
Triangle( p6, p7, p1, r, g, b, a, noDepthTest, flDuration ); // Shaft
Triangle( p1, p2, p6, r, g, b, a, noDepthTest, flDuration );
}
}
//-----------------------------------------------------------------------------
// Purpose : Draw a horizontal arrow pointing in the specified direction by yaw value
//-----------------------------------------------------------------------------
void NDebugOverlay::YawArrow( const Vector &startPos, float yaw, float length, float width, int r, int g, int b, int a, bool noDepthTest, float flDuration)
{
Vector forward = UTIL_YawToVector( yaw );
HorzArrow( startPos, startPos + forward * length, width, r, g, b, a, noDepthTest, flDuration );
}
//--------------------------------------------------------------------------------
// Purpose : Draw a vertical arrow at a position
//--------------------------------------------------------------------------------
void NDebugOverlay::VertArrow( const Vector &startPos, const Vector &endPos, float width, int r, int g, int b, int a, bool noDepthTest, float flDuration)
{
Vector lineDir = (endPos - startPos);
VectorNormalize( lineDir );
Vector upVec;
Vector sideDir;
float radius = width / 2.0;
VectorVectors( lineDir, sideDir, upVec );
Vector p1 = startPos - upVec * radius;
Vector p2 = endPos - lineDir * width - upVec * radius;
Vector p3 = endPos - lineDir * width - upVec * width;
Vector p4 = endPos;
Vector p5 = endPos - lineDir * width + upVec * width;
Vector p6 = endPos - lineDir * width + upVec * radius;
Vector p7 = startPos + upVec * radius;
// Outline the arrow
Line(p1, p2, r,g,b,noDepthTest,flDuration);
Line(p2, p3, r,g,b,noDepthTest,flDuration);
Line(p3, p4, r,g,b,noDepthTest,flDuration);
Line(p4, p5, r,g,b,noDepthTest,flDuration);
Line(p5, p6, r,g,b,noDepthTest,flDuration);
Line(p6, p7, r,g,b,noDepthTest,flDuration);
if ( a > 0 )
{
// Fill us in with triangles
Triangle( p5, p4, p3, r, g, b, a, noDepthTest, flDuration ); // Tip
Triangle( p1, p7, p6, r, g, b, a, noDepthTest, flDuration ); // Shaft
Triangle( p6, p2, p1, r, g, b, a, noDepthTest, flDuration );
// And backfaces
Triangle( p3, p4, p5, r, g, b, a, noDepthTest, flDuration ); // Tip
Triangle( p6, p7, p1, r, g, b, a, noDepthTest, flDuration ); // Shaft
Triangle( p1, p2, p6, r, g, b, a, noDepthTest, flDuration );
}
}
//-----------------------------------------------------------------------------
// Purpose: Draw an axis
//-----------------------------------------------------------------------------
void NDebugOverlay::Axis( const Vector &position, const QAngle &angles, float size, bool noDepthTest, float flDuration )
{
Vector xvec, yvec, zvec;
AngleVectors( angles, &xvec, &yvec, &zvec );
xvec = position + (size * xvec);
yvec = position - (size * yvec); // Left is positive
zvec = position + (size * zvec);
Line( position, xvec, 255, 0, 0, noDepthTest, flDuration );
Line( position, yvec, 0, 255, 0, noDepthTest, flDuration );
Line( position, zvec, 0, 0, 255, noDepthTest, flDuration );
}
//-----------------------------------------------------------------------------
// Purpose: Draw circles to suggest a sphere
//-----------------------------------------------------------------------------
void NDebugOverlay::Sphere( const Vector &center, float radius, int r, int g, int b, bool noDepthTest, float flDuration )
{
Vector edge, lastEdge;
float axisSize = radius;
Line( center + Vector( 0, 0, -axisSize ), center + Vector( 0, 0, axisSize ), r, g, b, noDepthTest, flDuration );
Line( center + Vector( 0, -axisSize, 0 ), center + Vector( 0, axisSize, 0 ), r, g, b, noDepthTest, flDuration );
Line( center + Vector( -axisSize, 0, 0 ), center + Vector( axisSize, 0, 0 ), r, g, b, noDepthTest, flDuration );
lastEdge = Vector( radius + center.x, center.y, center.z );
float angle;
for( angle=0.0f; angle <= 360.0f; angle += 22.5f )
{
edge.x = radius * cosf( angle / 180.0f * M_PI ) + center.x;
edge.y = center.y;
edge.z = radius * sinf( angle / 180.0f * M_PI ) + center.z;
Line( edge, lastEdge, r, g, b, noDepthTest, flDuration );
lastEdge = edge;
}
lastEdge = Vector( center.x, radius + center.y, center.z );
for( angle=0.0f; angle <= 360.0f; angle += 22.5f )
{
edge.x = center.x;
edge.y = radius * cosf( angle / 180.0f * M_PI ) + center.y;
edge.z = radius * sinf( angle / 180.0f * M_PI ) + center.z;
Line( edge, lastEdge, r, g, b, noDepthTest, flDuration );
lastEdge = edge;
}
lastEdge = Vector( center.x, radius + center.y, center.z );
for( angle=0.0f; angle <= 360.0f; angle += 22.5f )
{
edge.x = radius * cosf( angle / 180.0f * M_PI ) + center.x;
edge.y = radius * sinf( angle / 180.0f * M_PI ) + center.y;
edge.z = center.z;
Line( edge, lastEdge, r, g, b, noDepthTest, flDuration );
lastEdge = edge;
}
}
//-----------------------------------------------------------------------------
// Purpose: Draw a circle whose center is at a position, facing the camera
//-----------------------------------------------------------------------------
void NDebugOverlay::Circle( const Vector &position, float radius, int r, int g, int b, int a, bool bNoDepthTest, float flDuration )
{
CBasePlayer *player = GetLocalPlayer();
if ( player == NULL )
return;
Vector clientForward;
player->EyeVectors( &clientForward );
QAngle vecAngles;
VectorAngles( clientForward, vecAngles );
Circle( position, vecAngles, radius, r, g, b, a, bNoDepthTest, flDuration );
}
//-----------------------------------------------------------------------------
// Purpose: Draw a circle whose center is at a position and is facing a specified direction
//-----------------------------------------------------------------------------
void NDebugOverlay::Circle( const Vector &position, const QAngle &angles, float radius, int r, int g, int b, int a, bool bNoDepthTest, float flDuration )
{
// Setup our transform matrix
matrix3x4_t xform;
AngleMatrix( angles, position, xform );
Vector xAxis, yAxis;
// default draws circle in the y/z plane
MatrixGetColumn( xform, 2, xAxis );
MatrixGetColumn( xform, 1, yAxis );
Circle( position, xAxis, yAxis, radius, r, g, b, a, bNoDepthTest, flDuration );
}
void NDebugOverlay::Circle( const Vector &position, const Vector &xAxis, const Vector &yAxis, float radius, int r, int g, int b, int a, bool bNoDepthTest, float flDuration )
{
const unsigned int nSegments = 16;
const float flRadStep = (M_PI*2.0f) / (float) nSegments;
Vector vecLastPosition;
// Find our first position
// Retained for triangle fanning
Vector vecStart = position + xAxis * radius;
Vector vecPosition = vecStart;
// Draw out each segment (fanning triangles if we have an alpha amount)
for ( int i = 1; i <= nSegments; i++ )
{
// Store off our last position
vecLastPosition = vecPosition;
// Calculate the new one
float flSin, flCos;
SinCos( flRadStep*i, &flSin, &flCos );
vecPosition = position + (xAxis * flCos * radius) + (yAxis * flSin * radius);
// Draw the line
Line( vecLastPosition, vecPosition, r, g, b, bNoDepthTest, flDuration );
// If we have an alpha value, then draw the fan
if ( a && i > 1 )
{
if ( debugoverlay )
{
debugoverlay->AddTriangleOverlay( vecStart, vecLastPosition, vecPosition, r, g, b, a, bNoDepthTest, flDuration );
}
}
}
}
void NDebugOverlay::Sphere( const Vector &position, const QAngle &angles, float radius, int r, int g, int b, int a, bool bNoDepthTest, float flDuration )
{
// Setup our transform matrix
matrix3x4_t xform;
AngleMatrix( angles, position, xform );
Vector xAxis, yAxis, zAxis;
// default draws circle in the y/z plane
MatrixGetColumn( xform, 0, xAxis );
MatrixGetColumn( xform, 1, yAxis );
MatrixGetColumn( xform, 2, zAxis );
Circle( position, xAxis, yAxis, radius, r, g, b, a, bNoDepthTest, flDuration ); // xy plane
Circle( position, yAxis, zAxis, radius, r, g, b, a, bNoDepthTest, flDuration ); // yz plane
Circle( position, xAxis, zAxis, radius, r, g, b, a, bNoDepthTest, flDuration ); // xz plane
}