Learning Processing: A Beginner's Guide to Programming Images ...

240 Learning Processing
Processing will also allow for rotation around the x or y -axis with the functions rotateX( ) and rotateY( ) ,
which each require P3D or OPENGL mode. Th e function rotateZ( ) also exists and is the equivalent of
rotate( ). See Examples 14-6, 14-7 and 14-8.
fi g. 14.17 fi g. 14.18
fi g. 14.19
Example 14-6: rotateZ Example 14-7: rotateX Example 14-8: rotateY
float theta = 0.0;
void setup() {
size(200,200,P3D);
}
void draw() {
background(255);
stroke(0);
fill(175);
translate(width/2,
height/2);
rotateZ(theta);
rectMode(CENTER);
rect(0,0,100,100);
theta + = 0.02;
}
Th e rotate functions can also be used in combination. Th e results of Example 14-9 are shown in Figure 14.20 .
Example 14-9: Rotate around more than one axis
void setup() {
size(200,200,P3D);
}
void draw() {
background(255);
stroke(0);
fill(175);
translate(width/2,height/2);
rotateX(PI*mouseY/height);
rotateY(PI*mouseX/width);
rectMode(CENTER);
rect(0,0,100,100);
}
float theta = 0.0;
void setup() {
size(200,200,P3D);
}
void draw() {
background(255);
stroke(0);
fill(175);
translate(width/2,
height/2);
rotateX(theta);
rectMode(CENTER);
rect(0,0,100,100);
theta + = 0.02;
}
float theta = 0.0;
void setup() {
size(200,200,P3D);
}
void draw() {
background(255);
stroke(0);
fill(175);
translate(width/2,
height/2);
rotateY(theta);
rectMode(CENTER);
rect(0,0,100,100);
theta + = 0.02;
}
fi g. 14.20