arduinoでマンデルブロ

概要

arduinoでマンデルブロやってみた。

写真

サンプルコード

#include <Adafruit_GFX.h>
#include "Adafruit_TFTLCD.h"

#define XP            8
#define YP            A3
#define XM            A2
#define YM            9
#define TS_MINX      150 - 40
#define TS_MAXX      920 - 40
#define TS_MINY      120 - 40
#define TS_MAXY      940 - 40
#define LCD_CS        A3
#define LCD_CD        A2
#define LCD_WR        A1
#define LCD_RD        A0
#define LCD_RESET      A4
#define BLACK          0x0000
#define BLUE            0x001F
#define RED          0xF800
#define GREEN          0x07E0
#define CYAN            0x07FF
#define MAGENTA      0xF81F
#define YELLOW        0xFFE0
#define WHITE          0xFFFF
#define MINPRESSURE  10
#define MAXPRESSURE  1000

Adafruit_TFTLCD tft(LCD_CS, LCD_CD, LCD_WR, LCD_RD, LCD_RESET);

const int MAX = 256;
float cx, 
    cy;
float zoom = 1.0f;
void mandelbrot(float x1, float y1, float x2, float y2) {
    unsigned int i,
        j;
    uint16_t iter;
    uint16_t color;
    float sy = y2 - y1;
    float sx = x2 - x1;
    for(i = 0; i < tft.width(); i++) 
    {
        for(j = 0; j < tft.height(); j++) 
        {
            float cy = j * sy / tft.height() + y1;
            float cx = i * sx / tft.width() + x1;
            float x = 0.0f, 
                y = 0.0f, 
                xx = 0.0f, 
                yy = 0.0f;
            for(iter = 0; iter <= MAX && (xx + yy) < 4.0f; iter++) 
            {
                xx = x * x;
                yy = y * y;
                y = 2.0f * x * y + cy;
                x = xx - yy + cx;
            }
            color = ((iter << 7 & 0xF8) << 8) | ((iter << 4 & 0xFC) << 3) | (iter >> 3);
            tft.drawPixel(i, j, color);
        }
    }
}

void setup(void) {
    int i;
    tft.reset();
    uint16_t identifier = 0x9341;
    tft.begin(identifier);
    tft.fillScreen(BLACK);
    cx = -0.086f;
    cy = 0.55f;
}
void loop() { 
    mandelbrot(-2.0f * zoom + cx, -1.5f * zoom + cy, 2.0f * zoom + cx, 1.5f * zoom + cy);
    zoom *= 0.7f;
    if (zoom <= 0.00001f)
        zoom = 1.0f;
}

以上。