1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
|
/*
* Copyright (c) 2015 Camil Staps
*/
package com.camilstaps.mandelbrot;
import fractals.Grid;
/**
* Showing the Mandelbrot fractal on the screen
* @author camilstaps
*/
public class MandelbrotView {
private final MandelbrotProvider mandelbrotProvider;
private final Grid grid;
/**
* Get info from a MandelbrotProvider; work with a Grid
* @param mp
* @param grid
*/
public MandelbrotView(MandelbrotProvider mp, Grid grid) {
mandelbrotProvider = mp;
this.grid = grid;
}
/**
* Get the 'mathematical' x value for a certain x coordinate of the screen
* @param x_on_screen
* @return
*/
public double getX(int x_on_screen) {
double centerX = mandelbrotProvider.getCenterX();
double scale = mandelbrotProvider.getScale();
int grid_w = grid.getWidth();
double min_x = centerX - grid_w / scale / 2,
max_x = centerX + grid_w / scale / 2;
return min_x + ((double) x_on_screen) * (max_x - min_x) / grid_w;
}
/**
* Get the 'mathematical' y value for a certain y coordinate of the screen
* @param y_on_screen
* @return
*/
public double getY(int y_on_screen) {
double centerY = mandelbrotProvider.getCenterY();
double scale = mandelbrotProvider.getScale();
int grid_h = grid.getHeight();
double min_y = centerY - grid_h / scale / 2,
max_y = centerY + grid_h / scale / 2;
return min_y + (((float) y_on_screen) * (max_y - min_y) / grid_h);
}
/**
* (Re)draw the fractal
*/
public void redraw() {
int repetitions = mandelbrotProvider.getRepetitions();
int grid_w = grid.getWidth(), grid_h = grid.getHeight();
for (int i = 0; i < grid_w; i++) {
for (int j = 0; j < grid_h; j++) {
// Convert mandel number to some number in [0,pi] to let the colourise below work nicely
double mandel = ((double) Mandelbrot.mandelNumber(getX(i), getY(j), repetitions) * Math.PI) / repetitions;
// Different mandel numbers have different colours
int[] colour = {
(int) (30 + 220 * Math.sin(mandel)),
(int) (30 + 220 * Math.sin(mandel + 2 * Math.PI / 3)),
(int) (30 + 220 * Math.sin(mandel + 4 * Math.PI / 3))};
// This is a grayscale version:
//int[] color = {(int) (255 * mandel), (int) (255 * mandel), (int) (255 * mandel)};
grid.setPixel(i, j, colour);
}
}
}
/**
* Get user input
*/
public interface MandelbrotProvider {
/**
* Get center X value
* @return
*/
public double getCenterX();
/**
* Get center Y value
* @return
*/
public double getCenterY();
/**
* Get scale factor
* @return
*/
public double getScale();
/**
* Get max amount of iterations for the mandel function
* @return
*/
public int getRepetitions();
}
}
|
