Note

圣诞树---C语言

2022年07月13日 Wednesday · 2 min read
源程序

效果图 :

vFGRdf.png

源代码 :

#include <math.h>
#include <stdio.h>
#include <stdlib.h>
#include <Windows.h>
#define PI 3.1415926
float x, y;
float sdCircle(float px, float py, float r) 
{
    float dx = px - x, dy = py - y;
    return sqrtf(dx * dx + dy * dy) - r;
}
float opUnion(float d1, float d2)
{
    return d1 < d2 ? d1 : d2;
}
#define T px + scale * r * cosf(theta), py + scale * r * sin(theta)

float f(float px, float py, float theta, float scale, int n)
{
    float d = 0.0f;
    for (float r = 0.0f; r < 0.8f; r += 0.02f)
        d = opUnion(d, sdCircle(T, 0.05f * scale * (0.95f - r)));
    if (n > 0)
        for (int t = -1; t <= 1; t += 2) {
            float tt = theta + t * 1.8f;
            float ss = scale * 0.9f;
            for (float r = 0.2f; r < 0.8f; r += 0.1f) {
                d = opUnion(d, f(T, tt, ss * 0.5f, n - 1));
                ss *= 0.8f;
            }
        }
    return d;
}
int main(int argc, char* argv[]) 
{
    int n = argc > 1 ? atoi(argv[1]) : 3;
    for (y = 0.8f; y > 0.0f; y -= 0.02f, putchar('\n'))
        for (x = -0.35f; x < 0.35f; x += 0.01f)
            putchar(f(0, 0, PI * 0.5f, 1.0f, n) < 0 ? '*' : ' ');
}