MEL Lecture 2

 

 

 

 

sphere -radius 1.0 -axis 0 1 0 -name ball; move -2 2 0;

cone -radius 1.0 -axis 0 1 0 - name cone; move 2 2 0;

 

 

 

 

 

 

 

 

(1)

 

 

if (frame % 10 == 0){ // page 83 (modulus) and page 86 (comparison operators)

 

 

float $x = ball.tx;

float $y = ball.ty;

float $z = ball.tz;

 

 

ball.tx = cone.tx;

ball.ty = cone.ty;

ball.tz = cone.tz;

 

 

cone.tx = $x;

cone.ty = $y;

cone.tz = $z;

}

 

 

 

 

 

 

 

 

 

 

(2)

 

 

float $ballS;

float $coneS;

 

 

if (frame == 0) {

$ballS = ball.sx;

$coneS = cone.sx;

cone.sx = cone.sy = cone.sz = 0.;

}

else {

 

 

if (frame <= 15) {

ball.sx = ball.sy = ball.sz = (15. - frame) * $ballS / 14.;

cone.sx = cone.sy = cone.sz = (frame - 1.) * $coneS / 14.;

}

else if (frame <= 30) {

ball.sx = ball.sy = ball.sz = (30. - frame) * $coneS / 14.;

cone.sx = cone.sy = cone.sz = (frame - 16.) * $ballS / 14.;

}

}

 

 

 

 

 

 

OR

 

 

 

 

 

 

float $ballS;

float $coneS;

 

 

if (frame == 0) {

$ballS = ball.sx;

$coneS = cone.sx;

cone.sx = cone.sy = cone.sz = 0.;

}

 

 

if (frame >= 1 && frame <= 15) { // page 88 (logical operators).

ball.sx = ball.sy = ball.sz = (15. - frame) * $ballS / 14.;

cone.sx = cone.sy = cone.sz = (frame - 1.) * $coneS / 14.;

}

 

 

if (frame >= 16 && frame <= 30) {

ball.sx = ball.sy = ball.sz = (30. - frame) * $coneS / 14.;

cone.sx = cone.sy = cone.sz = (frame - 16.) * $ballS / 14.;

}

 

 

 

 

 

 

 

 

(3)

sphere -radius 1.0 -axis 0 1 0 -name ball; move -4 0 0;

sphere -radius 1.0 -axis 0 1 0 -name ball; move -2 0 0;

sphere -radius 1.0 -axis 0 1 0 -name ball; move 0 0 0;

sphere -radius 1.0 -axis 0 1 0 -name ball; move 2 0 0;

sphere -radius 1.0 -axis 0 1 0 -name ball; move 4 0 0;

 

 

 

 

(4)

cone -radius 1.0 -axis 0 1 0 - name cone; move -4 0 0;

cone -radius 1.0 -axis 0 1 0 - name cone; move -2 0 0;

cone -radius 1.0 -axis 0 1 0 - name cone; move 0 0 0;

cone -radius 1.0 -axis 0 1 0 - name cone; move 2 0 0;

cone -radius 1.0 -axis 0 1 0 - name cone; move 4 0 0;

 

 

 

 

(5)

if (rand( 0., 1.) < .5) sphere -radius 1.0 -axis 0 1 0 -name ball; else cone -radius 1.0 -axis 0 1 0 - name cone; move -4 0 0;

if (rand( 0., 1.) < .5) sphere -radius 1.0 -axis 0 1 0 -name ball; else cone -radius 1.0 -axis 0 1 0 - name cone; move -2 0 0;

if (rand( 0., 1.) < .5) sphere -radius 1.0 -axis 0 1 0 -name ball; else cone -radius 1.0 -axis 0 1 0 - name cone; move 0 0 0;

if (rand( 0., 1.) < .5) sphere -radius 1.0 -axis 0 1 0 -name ball; else cone -radius 1.0 -axis 0 1 0 - name cone; move 2 0 0;

if (rand( 0., 1.) < .5) sphere -radius 1.0 -axis 0 1 0 -name ball; else cone -radius 1.0 -axis 0 1 0 - name cone; move 4 0 0;

 

 

 

 

(5a)

(in scene, select all objects)

string $obj[] = `ls -sl`;

print $obj;

 

 

 

 

OR

 

 

 

 

string $obj[] = `ls "sphere" "sphere?" "sphere??" "cone" "cone?" "cone??"`;

print $obj;

 

 

 

 

 

 

(6)

string $spheres[] = `ls "sphere" "sphere?" "sphere??"`;

int $numSpheres = size( $spheres ); // page 73.

print $numSpheres;

 

 

string $cones[] = `ls "cone" "cone?" "cone??"`;

int $numCones = size( $cones );

print $numCones;

 

 

 

 

 

 

 

 

(3+)

LOOPS:

 

 

 

 

Initialization

Test

Do Something

Increment

 

 

 

 

 

 

Initialize variable(s)

while ( test-using-variable is true ) {

Do Something

Increment variable(s)

}

 

 

 

 

 

 

 

 

int i = 0;

int $x = -4;

while ($i < 5) { // page 93

sphere -radius 1.0 -axis 0 1 0 -name ball; move $x 0 0;

$x = $x + 2;

$i = $i + 1;

}

 

 

 

 

 

 

OR

 

 

 

 

 

 

 

 

int i = 0;

int $x = -4;

while ($i < 5) {

sphere -radius 1.0 -axis 0 1 0 -name ball; move $x 0 0;

$x += 2;

$i++;

}

 

 

 

 

 

 

OR

 

 

 

 

 

 

 

 

int $x = -4;

while ($x <= 4) {

sphere -radius 1.0 -axis 0 1 0 -name ball; move $x 0 0;

$x += 2;

}