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MEL Scriptingfor Maya Animators

Mark R. WilkinsChris KazmierWith contribution fromStephan Osterburg .

MORGAN KAUFMANN PUBLISHERSAN IMPRINT OF ELSEVIER SCIENCE

www.mkp.com

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MAYA:

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2004

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MEL - Maya . no MEL, - , .

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ISBN 1-55860-841-9ISBN 5-93378-097-9

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! 19034, , ., . 21, 1. .: 333-82-11, [email protected] 16.06.04 70x90/16. . r i i " i ; i i i . ^- .. . . 35,1. 2000. : 1302 117623, . , . , . 10.

ISBN 1-55860-841-9ISBN 5-93378-097-9 -, 2004

Copyright 2003 by Elsevier Science (USA)Translation Copyright 2004by.KUDITS-OBRAZA l l rights reserved. 2003 Elsevier Science () 2004 - .

Maya: MEL MEL.

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56 MEL Maya

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translateX = $xval;translateY - Syval;

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60 MEL Maya

target1!, . target2 , 0 (, , , , ).

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3. 63

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// aimConstraint

nurbsSpherel_aimConstraint1.targetlWO - $eye1_coord_target1_weight;nurbsSphere2_aimConstraint1.targetlWO = $eye2_coord_target1_weight;nurbsSpnere1_aimConstraint1,target2W1 - $eye"Lcoord_target2_weight;nurbsSphere2_aimConstraint1.target2W1 - $eye2_coord_target2_weight;

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float $eye1_coord_target1_weight;float $eye1_coord_target2_weight;

float $eye2_coord_target1_weight;float $eye2_coord_target2_weight;// target2// eyes.target , // target2, eyes.target 2, // , ^yes.target 1

$eye1_coord_target2_weight = eyes,target - 1;Seye2_coord_target2_weight - eyes.target - 1;

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$eye1_coord_target1_weight = 1 - $eyel_coord_target2_weight;$eye2_coord_target1_weight - 1 - $eye2_coord_target2_weight;

64 MEL Maya

I/ aimConstralnt

nurbsSphere1_aimConstraint1.target1WO = $eyel_coord_targetl_weight; rbsSphere2_aimConstraint1. target"! WO -~ $eye2_coord_target1_weight;nurbsSphere1_aimConstraint1,target2W1 = $eye1_coord_target2_welght;nurbsSphere2_aimConstraint1.target2W1 - $eye2_coord_target2_weight;

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3. 65

float $eye1_uncoord_targett_weight = 1;float $eye1_uncoord_target2_weight - 0;float $eye2_uncoord_target~l_weight = 0;float $eye2_uncoord_target2_weight - 1;

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nurbsSphere2_aimConstraint1.targetlWO -(eyes.coordination * $eye2_coord_target1_weight) +((1 - eyes.coordination) * $eye2_unccord_target1_weight);

nurbsSphere1_aimConstraint1.target2W1 =(eyes.coordination * $eye1_coord_target2_weight) +((1 - eyes.coordination) * $eye1_unccord_target2_weight);

nurbsSpnere2_aimConstraint1.target2W1 =. (eyes.coordination * $eye2_coord_target2j/ight) +

((1 - eyes.coordination) * $eye2_unccord_target2_weight); eyes.coordination ,

. eyes.coordination 1, . , , 0.5 - .

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66 MEL Maya

:

1. eyes, Attribute Editor coordination , target . , , - 0, - 1, - 1.

2. Expression Editor, By Expression Name Selection Filter expression!. :

// // , 1

float $eye~l_coord_target1_weight;float $eye"l_coord_target2_weignt;float $eye2_coord_target1_weight;float $eye2_coord_target2_weight;// coordination , 1 // target"!, a eye2 target2

float $eye1_uncoord_target1_weight = 1;float $eye1__uncoord_target2_weight = 0;float $eye2_uncoord_target1jeight = 0;float $eye2_uncoord_target2_weignt - 1;// target2// eyes.target , // target2, eyes.target 2. // , eyes.target 1

$eye1_coord_target2_weight = eyes,target - 1;$eye2_coord_target2__weight - eyes.tarcet - 1;$eye1_coord_target1_weight = 1 - $eye1_coord_target2_weight;$eye2_coord_target1_weight = 1 - $eye2_coord_target2_weight;// //

nurbsSphere1_aimConstraint1.targetlWO -(eyes.coordination * $eye1_coord_target1_weight) +((1 - eyes.coordination) * $eye"Lunccord_target1_weight);

3. 67

nurbsSphere2_ainConstraint1.target1WO -(eyes.coordination * $eye2_coord__target1_weight) +((1 - eyes.coordination) * $eye2_unccord_target1_weight);

nurbsSpnere1_aimConstraint1.target2W1 =(eyes.coordination * $eye1_coord_target2_weight) +((1 - eyes.coordination) * $eye1_unccord_target2_weight);

nurbsSphere2_aimConstraint1.target2W1 =(eyes.coordination * $eye2_coord_target2_weight) +((1 - eyes.coordination) * $eye2_unccord_target2_weight);

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70 MEL Maya

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72 MEL Maya

angle angle (. . 4.3). , ,

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vector $xvec = 1,0,0; // Xvector $yvec = 0,1,0; // Yfloat $xy_angle = angle ($xvec, $yvec); // 1.570796 $pi = 3.141593;float $xy_angle_degrees = $xy_angle * 180/$pi; // 90

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4. 73

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rot {Smyvec. $z axis, (twenty degrees)

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if (tz > -5) {magnitude = 5.0;

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78 MEL Maya

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82 MEL Maya

Attribute Editor: pWUCMl

particle! partideSriapsI 1 Erniuel I

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84 MEL __

( ) $posY. , , $. , - Y- , . Y- X Z .

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86 MEL Maya

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4. 87

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float $pos[] = 'pointOnCurve -pr Cage) -p curve!';float $tan[] = 'pointOnCurve -pr (age) -nt curve!';float $norm[] = 'pointOnCurve -pr (age) -nn curve!';

vector Sposvec = ;vector $tanvec = ;vector Snormvec = ;

vector $norm2vec = cross ($tanvec, Snormvec);position - $posvec + ($scaleOffset'$normvec*cos(age*20))+

($scaleOffset*$norm2vec*sin(age'20));

-

88 MEL Maya

8. Create.9. Expressions After Dynamics on Channel Box.

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float SscaleOffset - 0.2; ,

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4. 89

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string $selection_list[] = *ls -si';// , // ( , // , )string ScurveSelected = $selection_Hst[0];float SstartOffset = 0.1;

float Sspeed = (1.0 / 24.0) ;offsetCurve -d $startOffset -n ($curveSelected + "guide");float $startPoint[] = 'pointOnCurve -pr 0 -p ScurveSelected';

float $startTangent[] - *pointOnCurve -pr 0 -nt ScurveSelected';

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Select -r (ScurveSelected + "particlesShape");

5. MEL- 111

addAttr -In "speed" -at "float":

setAtt (ScurveSelected + "particlesShape.speed") Sspeed;

addAttr -In "scaleQffset" -at "float";

setAttr ($curveSelected + "particlesShape.scaleOffset") $startQffset;connectDynamic -em ($curveSelected + "emitter")

($curve$elected + "particles");parent (ScurveSeLected + "emitter") ScurveSelected;

string SmainCurvelnfoNode = 'pointOnCurve -ch on -pr 0 ScurveSelected';

string SguideCurvelnfoNode = 'pointOnCurve -ch on -pr 0 ($curveSelected + "guide")";//

string $exrString ="float $curve_param = " + $curveSelected + "particlesShape.age * " +ScurveSelected + "particlesShape.speed;\n" +

"setAttr" + $mainCurve!nfoNode + ".parameter $curve_param;\n" +"setAttr " + SguideCurvelnfoNode + ".parameter $curve_pararn;\n" +

"float $pos[] = 'getAttr " * SmainCurvelnfoNode + ". position'; \n" +"float $tan[] = %getAttr " + SmainCurvelnfoNode + ".normalizedTangent';\n" +."float $normEnd[] - 'getAttr " + $guideCurve!nfoNode + ". position';\n" +"float $norm[];\n" +"$norm[0] = $normEnd[0] - $pos[0];\n" +"$[1] = $normEnd[1] - $pos[1];\n" +"$norm[2] = $normEnd[2] - $pos[2];\n" 4-"vector Sposvec = $pos[0j, $pos[1]

s $pos[2];\n" +

"vector Stanvec =

112 ^ MEL Maya

"particlesShape.scaleOFfset * $normvec * cos(" +ScurveSelected + "particlesShape.age*20}} + \n" +" (" + ScurveSelected +"particlesShape.scaleOFfset * sin("+ScurveSelected + "particlesShape.age-20)) + \n";//

dynExpression - -s SexprString (ScurveSelected + "particles"};dynExpression -c -s $exprString ($curveSelected + "particles"};

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float $startTangent[] = 'pointOnCurve - 0 -nt ScurveSelected';float $startGuide[] = ' pointOnCurve -pr 0 -p ($curveSelected + "guide") ' ;float $startNormal[]; '$startNormal[0] = $startGuide[0] - $startPoint[0];$startNormal[1] = $startGuide[1] - $startPoint[1];$startNormal[2] = $startGuide[2] - $startPoint[2];

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-n (ScurveSelected + "emitter") -spd 0.0-type dir;

114 MEL Maya

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setAttr (ScurveSelected + "particlesShape.scaleOffset") $start()ffset;, , -

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str ing S m a i n C u r v e l n f o N o d e = 'pointOnCurve -ch on -pr 0 ScurveSelected';

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"setAttr" + $mainCurve!nfoNode + ".parameter $curve_param;\n" +"setAttr" + $guideCurveInfoNode + ".parameter $curve_param; \n" +"float $pos[] = 'getAttr " + SmainCurvelnfoNode + ".position';\n" +"float $tan[] = 'getAttr " + SmainCurvelnfoNode + ".normalizedTangent';\n" +

116 MEL Maya

"float $normEnd[] = 'getAttr " + $guitieCurveInfoNode + "-positicn';\n" +"float $norm[];\n" + "$norm[0] - $norrnEnd[0] - $pos[0];\n" +"$norm[1] = $normEnd[1] - $pos[1];\n" +"$norra[2] = $normEnd[2] - $pos[2];\rT +"vector Sposvec =

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assign_four();print($my_int);

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. float() ( , , -

, ,

MEL-). , -

:

p r i n t (float(3));

6. 127

, 3, , - 3 . Maya , 0, , , Maya . 3 f loat(3) :print (float(3) / 4);

0,75, 0, , . ,

, .

,

, ()., , . -

, $ $ :int $a -14;int $b = 3;

, -

:

print ($ - ($ * ($ / $))) ; , 2, -

, .

, , :

pr int ($a % $ ) ; (%) ( m o d u l u s )

, , $ $. : a mod b.

. -

,

+=, -=, *=, /= %=. ,$ = $ + 4;

, :

$ += 4; ,

$ - $ % 3; , :

$ %= 3;

128 MEL ^

. -

++ . :

$ = $ + 1; :

$++; :

$ = $ - 1; , :

$--; ( )

,

, , Maya .

. 9, - , , .

.

:

print (5 > ); // print (5 < 6); // print (5 >= 6); // print (5