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53 lines
892 B
Plaintext
53 lines
892 B
Plaintext
/**
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* PolarToCartesian
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* by Daniel Shiffman.
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*
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* Convert a polar coordinate (r,theta) to cartesian (x,y):
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* x = r * cos(theta)
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* y = r * sin(theta)
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*/
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float r;
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// Angle and angular velocity, accleration
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float theta;
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float theta_vel;
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float theta_acc;
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void setup() {
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size(640, 360);
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// Initialize all values
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r = height * 0.45;
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theta = 0;
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theta_vel = 0;
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theta_acc = 0.0001;
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}
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void draw() {
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background(0);
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// Translate the origin point to the center of the screen
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translate(width/2, height/2);
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// Convert polar to cartesian
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float x = r * cos(theta);
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float y = r * sin(theta);
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// Draw the ellipse at the cartesian coordinate
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ellipseMode(CENTER);
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noStroke();
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fill(200);
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ellipse(x, y, 32, 32);
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// Apply acceleration and velocity to angle (r remains static in this example)
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theta_vel += theta_acc;
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theta += theta_vel;
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}
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