// ===========================================================================
// Copyright 2018 Autodesk, Inc. All rights reserved.
//
// Use of this software is subject to the terms of the Autodesk license
// agreement provided at the time of installation or download, or which
// otherwise accompanies this software in either electronic or hard copy form.
// ===========================================================================
//
//
//  Creation Date:  2000
//
// Description:	Creates random strokes of selected paint effects brush
//			on selected surfaces.
//	

global proc paintRandom( int $udensity, int $vdensity, float $strokeLength, float $randOffset, 
float $sampleDensity, int $arcLengthDensity, float $surfaceOffsetMin, float $surfaceOffsetMax, 
int $doClip, int $shareOneBrush )
{
	string $selected[] = `ls -sl -dag -type nurbsSurface -type mesh`;
	string $sel;

	if( size( $selected ) <= 0  )
	{
		warning( uiRes("m_paintGrid.kNoSurfacesSelected") );
		return;
	}	
	int $uspan, $vspan;
	float $u,$v,$minU, $minV, $rangeU, $rangeV;
	string $cmdK = "-k 0 -k 1 ";
	string $newStrokes[], $newCurves[], $newStroke[];
	int $numNewStrokes = 0;
	if( $udensity < 1 )
		$udensity = 1;
	if( $vdensity < 1 )
		$vdensity = 1;

	float $uscale = 1.0/(float)$udensity;
	float $vscale = 1.0/(float)$vdensity;
	rand( $uscale ); // the first rand is sometimes bad
	for( $sel in $selected )
	{
		if(`objectType -isType nurbsSurface $sel`)
		{
			$minU = getAttr( $sel+".minValueU" );
			$minV = getAttr( $sel+".minValueV" );
			$rangeU = getAttr( $sel+".maxValueU" ) - $minU;
			$rangeV = getAttr( $sel+".maxValueV" ) - $minV;
		}
		else
		{
			$minU = 0.0;
			$minV = 0.0;
			$rangeU = 1.0;
			$rangeV = 1.0;
		}

		for( $uspan = 0; $uspan < $udensity; $uspan++ ) 
		{
			for( $vspan = 0; $vspan < $vdensity; $vspan++ ) 
			{
				$u = (float)($uspan)/(float)($udensity);
				$v = (float)($vspan)/(float)($vdensity);
				$u += (0.5 + (rand( 1 )-0.5) * $randOffset) * $uscale;
				$v += (0.5 + (rand( 1 )-0.5) * $randOffset) * $vscale;
				// $u2 = rand( $uscale );
				// $v2 = rand( $vscale );
				$u2 = rand( 2 ) - 1;
				$v2 = rand( 2 ) - 1;
				$length = sqrt( $u2*$u2 + $v2*$v2 );
				if( $length == 0 )
					continue;
				$length = $strokeLength / $length;
				$u2 = $u + $u2*$length*$uscale;
				$v2 = $v + $v2*$length*$vscale;
				if( $doClip )
				{
					if( $u > 1 )
						$u = 1;
					else if( $u < 0 )
						$u = 0;
	
					if( $v > 1 )
						$v = 1;
					else if( $v < 0 )
						$v = 0;
	
					if( $u2 > 1 )
						$u2 = 1;
					else if( $u2 < 0 )
						$u2 = 0;
	
					if( $v2 > 1 )
						$v2 = 1;
					else if( $v2 < 0 )
						$v2 = 0;
	// TODO: modulate sampleDensity based on length change with clipping
				}		
				string $cmd = ("curveOnSurface -d 1 -uv " + ($u*$rangeU + $minU) + " " + ($v*$rangeV + $minV)
							  + " -uv "+ ($u2*$rangeU + $minU) +" "+ ($v2*$rangeV + $minV)
							  + " "+ $cmdK + $sel);
				$newCurves[$numNewStrokes] = `eval($cmd)`;
				convertCurvesToStrokes;
				$newStroke =  `ls -sl -dag -type stroke`;
				$newStrokes[ $numNewStrokes ] = $newStroke[0];
				$numNewStrokes++;
			}
		}
	}

	float $offsetRange = $surfaceOffsetMax -$surfaceOffsetMin;
	rand( $offsetRange ); // the first rand is sometimes bad
		float $maxCurveLength = 0;
	float $curveLengths[];
	for( $i = 0; $i < $numNewStrokes; $i++)
	{
		if( $arcLengthDensity )
		{
			$curveLengths[$i] = arclen ($newCurves[$i]);
			if( $curveLengths[$i] > $maxCurveLength )
			{
				$maxCurveLength = $curveLengths[$i];
			}
		}
		hide $newCurves[$i];
	}
	float $sDense = $sampleDensity;
	for( $i = 0; $i < $numNewStrokes; $i++)
	{
		if( $arcLengthDensity && $maxCurveLength > 0)
		{
			$sDense = $sampleDensity * $curveLengths[$i]/$maxCurveLength;
		}
		setAttr ( $newStrokes[$i] + ".sampleDensity" ) $sDense;
		setAttr ( $newStrokes[$i] + ".seed" ) $i;
		setAttr ( $newStrokes[$i] + ".surfaceOffset" ) ($surfaceOffsetMin + rand( $offsetRange ));
		select -add $newStrokes[$i];
	}
    if( $shareOneBrush )
    {
        useSameBrush;
    }

}