2021年10月28日星期四

week 6. 2D array & transform

Transform

review:
draw a rotating shape in the center of screen.

also use 'scale()' to change the size of the object.

using pushMatrix() and popMatrix()

using cos();

參考:
https://processing.org/examples/array2d.html

用 2D array 設定每個元素的顏色，旋轉速度，屬性。

float[][] distances;
float[][] rotateAngles;
float[][] rotateRates;
float maxDistance;
int spacer;

void setup() {
size(640, 360);
maxDistance = dist(width/2, height/2, width, height);
distances = new float[width][height];
rotateAngles = new float[width][height];
rotateRates = new float[width][height];
for (int y = 0; y < height; y++) {
for (int x = 0; x < width; x++) {
float distance = dist(width/2, height/2, x, y);
distances[x][y] = distance/maxDistance * 255;
rotateAngles[x][y] = random(5.0);
rotateRates[x][y] = random(5.0, 40.0);
}
}
spacer = 30;
strokeWeight(3);
//noLoop(); // Run once and stop
}

void draw() {
background(0);
// This embedded loop skips over values in the arrays based on
// the spacer variable, so there are more values in the array
// than are drawn here. Change the value of the spacer variable
// to change the density of the points
for (int y = 0; y < height; y += spacer) {
for (int x = 0; x < width; x += spacer) {
pushMatrix();
translate(x, y);
rotate(frameCount/rotateRates[x][y]+rotateAngles[x][y]);
rect(-spacer/2, -spacer/2, spacer, spacer);
stroke(distances[x][y]);
popMatrix();
}
}
}

transform example:

void setup(){

size(800, 600);

noFill();

stroke(255);

}

void draw() {

background(30);

pushMatrix();

translate(600, 400);

scale(cos(frameCount/60.0)*5.0);

rotate(frameCount/30.0);

rect(-32, -32, 64, 64);

popMatrix();

}

Practice:

Create an array of 3D shapes.

https://processing.org/tutorials/p3d/

2021年10月21日星期四

week 5. basic form and rotation

1. form: point, line, polygon, arc, eclipse, rect,...
2. noLoop(); / redraw();

void setup(){
size(640, 360);
background(0);
}

int gridSize = 40;

void draw() {
background(0);
stroke(200);
noFill();
for (int x = gridSize; x <= width - gridSize; x += gridSize) {
for (int y = gridSize; y <= height - gridSize; y += gridSize) {

rotateShape(x, y);

}
}

}

void rotateShape(int xloc, int yloc) {
pushMatrix();
translate(xloc, yloc);
// rotate((frameCount / 8.0)+xloc+yloc+mouseX);
rotate((mouseX/100)*frameCount / 8.0+xloc+yloc);
rect(-10, -10, 20, 20);
line(-10, -10, 10, 10);
popMatrix();

}

References:
https://processing.org/examples/star.html

example #2:

void setup(){
size(640, 360);
background(0);
}

int gridSize = 40;

void draw() {
background(0);
stroke(200);
noFill();
for (int x = gridSize; x <= width - gridSize; x += gridSize) {
for (int y = gridSize; y <= height - gridSize; y += gridSize) {

rotateShape(x, y);

}
}

}

void rotateShape(int xloc, int yloc) {
pushMatrix();
translate(xloc, yloc);
rotate((frameCount / 8.0)+xloc+yloc);
//rotate((mouseX/100)*frameCount / 8.0+xloc+yloc);
beginShape();
vertex(-10, -10);
vertex(0, -10);
vertex(0, 0);
vertex(10, 0);
vertex(10, 10);
vertex(-10, 10);
endShape(CLOSE);
//rect(-10, -10, 20, 20);
// line(-10, -10, 10, 10);
popMatrix();

}